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-rw-r--r--Documentation/atomic_t.txt94
-rw-r--r--drivers/staging/media/atomisp/pci/atomisp_ioctl.c4
-rw-r--r--include/asm-generic/atomic-long.h1014
-rw-r--r--include/asm-generic/bitops/atomic.h32
-rw-r--r--include/asm-generic/bitops/lock.h39
-rw-r--r--include/asm-generic/bitops/non-atomic.h39
-rw-r--r--include/linux/atomic.h7
-rw-r--r--include/linux/atomic/atomic-arch-fallback.h (renamed from include/linux/atomic-arch-fallback.h)0
-rw-r--r--include/linux/atomic/atomic-instrumented.h (renamed from include/asm-generic/atomic-instrumented.h)586
-rw-r--r--include/linux/atomic/atomic-long.h1014
-rw-r--r--include/linux/debug_locks.h3
-rw-r--r--include/linux/local_lock_internal.h86
-rw-r--r--include/linux/mutex.h92
-rw-r--r--include/linux/preempt.h4
-rw-r--r--include/linux/rbtree.h31
-rw-r--r--include/linux/rbtree_types.h34
-rw-r--r--include/linux/rtmutex.h63
-rw-r--r--include/linux/rwbase_rt.h39
-rw-r--r--include/linux/rwlock_rt.h140
-rw-r--r--include/linux/rwlock_types.h53
-rw-r--r--include/linux/rwsem.h78
-rw-r--r--include/linux/sched.h119
-rw-r--r--include/linux/sched/wake_q.h7
-rw-r--r--include/linux/spinlock.h15
-rw-r--r--include/linux/spinlock_api_smp.h3
-rw-r--r--include/linux/spinlock_rt.h159
-rw-r--r--include/linux/spinlock_types.h89
-rw-r--r--include/linux/spinlock_types_raw.h73
-rw-r--r--include/linux/static_call.h33
-rw-r--r--include/linux/ww_mutex.h50
-rw-r--r--kernel/Kconfig.locks2
-rw-r--r--kernel/futex.c556
-rw-r--r--kernel/locking/Makefile3
-rw-r--r--kernel/locking/mutex-debug.c5
-rw-r--r--kernel/locking/mutex-debug.h29
-rw-r--r--kernel/locking/mutex.c541
-rw-r--r--kernel/locking/mutex.h48
-rw-r--r--kernel/locking/rtmutex.c1170
-rw-r--r--kernel/locking/rtmutex_api.c590
-rw-r--r--kernel/locking/rtmutex_common.h135
-rw-r--r--kernel/locking/rwbase_rt.c263
-rw-r--r--kernel/locking/rwsem.c115
-rw-r--r--kernel/locking/semaphore.c4
-rw-r--r--kernel/locking/spinlock.c7
-rw-r--r--kernel/locking/spinlock_debug.c5
-rw-r--r--kernel/locking/spinlock_rt.c263
-rw-r--r--kernel/locking/ww_mutex.h569
-rw-r--r--kernel/locking/ww_rt_mutex.c76
-rw-r--r--kernel/rcu/tree_plugin.h6
-rw-r--r--kernel/sched/core.c109
-rw-r--r--lib/Kconfig.debug11
-rw-r--r--lib/test_lockup.c8
-rwxr-xr-xscripts/atomic/check-atomics.sh6
-rwxr-xr-xscripts/atomic/fallbacks/acquire4
-rwxr-xr-xscripts/atomic/fallbacks/add_negative6
-rwxr-xr-xscripts/atomic/fallbacks/add_unless6
-rwxr-xr-xscripts/atomic/fallbacks/andnot4
-rwxr-xr-xscripts/atomic/fallbacks/dec4
-rwxr-xr-xscripts/atomic/fallbacks/dec_and_test6
-rwxr-xr-xscripts/atomic/fallbacks/dec_if_positive6
-rwxr-xr-xscripts/atomic/fallbacks/dec_unless_positive6
-rwxr-xr-xscripts/atomic/fallbacks/fence4
-rwxr-xr-xscripts/atomic/fallbacks/fetch_add_unless8
-rwxr-xr-xscripts/atomic/fallbacks/inc4
-rwxr-xr-xscripts/atomic/fallbacks/inc_and_test6
-rwxr-xr-xscripts/atomic/fallbacks/inc_not_zero6
-rwxr-xr-xscripts/atomic/fallbacks/inc_unless_negative6
-rwxr-xr-xscripts/atomic/fallbacks/read_acquire2
-rwxr-xr-xscripts/atomic/fallbacks/release4
-rwxr-xr-xscripts/atomic/fallbacks/set_release2
-rwxr-xr-xscripts/atomic/fallbacks/sub_and_test6
-rwxr-xr-xscripts/atomic/fallbacks/try_cmpxchg4
-rwxr-xr-xscripts/atomic/gen-atomic-fallback.sh68
-rwxr-xr-xscripts/atomic/gen-atomic-instrumented.sh11
-rwxr-xr-xscripts/atomic/gen-atomic-long.sh10
-rwxr-xr-xscripts/atomic/gen-atomics.sh6
76 files changed, 5930 insertions, 2780 deletions
diff --git a/Documentation/atomic_t.txt b/Documentation/atomic_t.txt
index 0f1fdedf36bb..0f1ffa03db09 100644
--- a/Documentation/atomic_t.txt
+++ b/Documentation/atomic_t.txt
@@ -271,3 +271,97 @@ WRITE_ONCE. Thus:
SC *y, t;
is allowed.
+
+
+CMPXCHG vs TRY_CMPXCHG
+----------------------
+
+ int atomic_cmpxchg(atomic_t *ptr, int old, int new);
+ bool atomic_try_cmpxchg(atomic_t *ptr, int *oldp, int new);
+
+Both provide the same functionality, but try_cmpxchg() can lead to more
+compact code. The functions relate like:
+
+ bool atomic_try_cmpxchg(atomic_t *ptr, int *oldp, int new)
+ {
+ int ret, old = *oldp;
+ ret = atomic_cmpxchg(ptr, old, new);
+ if (ret != old)
+ *oldp = ret;
+ return ret == old;
+ }
+
+and:
+
+ int atomic_cmpxchg(atomic_t *ptr, int old, int new)
+ {
+ (void)atomic_try_cmpxchg(ptr, &old, new);
+ return old;
+ }
+
+Usage:
+
+ old = atomic_read(&v); old = atomic_read(&v);
+ for (;;) { do {
+ new = func(old); new = func(old);
+ tmp = atomic_cmpxchg(&v, old, new); } while (!atomic_try_cmpxchg(&v, &old, new));
+ if (tmp == old)
+ break;
+ old = tmp;
+ }
+
+NB. try_cmpxchg() also generates better code on some platforms (notably x86)
+where the function more closely matches the hardware instruction.
+
+
+FORWARD PROGRESS
+----------------
+
+In general strong forward progress is expected of all unconditional atomic
+operations -- those in the Arithmetic and Bitwise classes and xchg(). However
+a fair amount of code also requires forward progress from the conditional
+atomic operations.
+
+Specifically 'simple' cmpxchg() loops are expected to not starve one another
+indefinitely. However, this is not evident on LL/SC architectures, because
+while an LL/SC architecure 'can/should/must' provide forward progress
+guarantees between competing LL/SC sections, such a guarantee does not
+transfer to cmpxchg() implemented using LL/SC. Consider:
+
+ old = atomic_read(&v);
+ do {
+ new = func(old);
+ } while (!atomic_try_cmpxchg(&v, &old, new));
+
+which on LL/SC becomes something like:
+
+ old = atomic_read(&v);
+ do {
+ new = func(old);
+ } while (!({
+ volatile asm ("1: LL %[oldval], %[v]\n"
+ " CMP %[oldval], %[old]\n"
+ " BNE 2f\n"
+ " SC %[new], %[v]\n"
+ " BNE 1b\n"
+ "2:\n"
+ : [oldval] "=&r" (oldval), [v] "m" (v)
+ : [old] "r" (old), [new] "r" (new)
+ : "memory");
+ success = (oldval == old);
+ if (!success)
+ old = oldval;
+ success; }));
+
+However, even the forward branch from the failed compare can cause the LL/SC
+to fail on some architectures, let alone whatever the compiler makes of the C
+loop body. As a result there is no guarantee what so ever the cacheline
+containing @v will stay on the local CPU and progress is made.
+
+Even native CAS architectures can fail to provide forward progress for their
+primitive (See Sparc64 for an example).
+
+Such implementations are strongly encouraged to add exponential backoff loops
+to a failed CAS in order to ensure some progress. Affected architectures are
+also strongly encouraged to inspect/audit the atomic fallbacks, refcount_t and
+their locking primitives.
diff --git a/drivers/staging/media/atomisp/pci/atomisp_ioctl.c b/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
index 6f5fe5092154..c8a625667e81 100644
--- a/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
+++ b/drivers/staging/media/atomisp/pci/atomisp_ioctl.c
@@ -1904,8 +1904,8 @@ int __atomisp_streamoff(struct file *file, void *fh, enum v4l2_buf_type type)
dev_dbg(isp->dev, "Stop stream on pad %d for asd%d\n",
atomisp_subdev_source_pad(vdev), asd->index);
- BUG_ON(!rt_mutex_is_locked(&isp->mutex));
- BUG_ON(!mutex_is_locked(&isp->streamoff_mutex));
+ lockdep_assert_held(&isp->mutex);
+ lockdep_assert_held(&isp->streamoff_mutex);
if (type != V4L2_BUF_TYPE_VIDEO_CAPTURE) {
dev_dbg(isp->dev, "unsupported v4l2 buf type\n");
diff --git a/include/asm-generic/atomic-long.h b/include/asm-generic/atomic-long.h
deleted file mode 100644
index 073cf40f431b..000000000000
--- a/include/asm-generic/atomic-long.h
+++ /dev/null
@@ -1,1014 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-
-// Generated by scripts/atomic/gen-atomic-long.sh
-// DO NOT MODIFY THIS FILE DIRECTLY
-
-#ifndef _ASM_GENERIC_ATOMIC_LONG_H
-#define _ASM_GENERIC_ATOMIC_LONG_H
-
-#include <linux/compiler.h>
-#include <asm/types.h>
-
-#ifdef CONFIG_64BIT
-typedef atomic64_t atomic_long_t;
-#define ATOMIC_LONG_INIT(i) ATOMIC64_INIT(i)
-#define atomic_long_cond_read_acquire atomic64_cond_read_acquire
-#define atomic_long_cond_read_relaxed atomic64_cond_read_relaxed
-#else
-typedef atomic_t atomic_long_t;
-#define ATOMIC_LONG_INIT(i) ATOMIC_INIT(i)
-#define atomic_long_cond_read_acquire atomic_cond_read_acquire
-#define atomic_long_cond_read_relaxed atomic_cond_read_relaxed
-#endif
-
-#ifdef CONFIG_64BIT
-
-static __always_inline long
-atomic_long_read(const atomic_long_t *v)
-{
- return atomic64_read(v);
-}
-
-static __always_inline long
-atomic_long_read_acquire(const atomic_long_t *v)
-{
- return atomic64_read_acquire(v);
-}
-
-static __always_inline void
-atomic_long_set(atomic_long_t *v, long i)
-{
- atomic64_set(v, i);
-}
-
-static __always_inline void
-atomic_long_set_release(atomic_long_t *v, long i)
-{
- atomic64_set_release(v, i);
-}
-
-static __always_inline void
-atomic_long_add(long i, atomic_long_t *v)
-{
- atomic64_add(i, v);
-}
-
-static __always_inline long
-atomic_long_add_return(long i, atomic_long_t *v)
-{
- return atomic64_add_return(i, v);
-}
-
-static __always_inline long
-atomic_long_add_return_acquire(long i, atomic_long_t *v)
-{
- return atomic64_add_return_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_add_return_release(long i, atomic_long_t *v)
-{
- return atomic64_add_return_release(i, v);
-}
-
-static __always_inline long
-atomic_long_add_return_relaxed(long i, atomic_long_t *v)
-{
- return atomic64_add_return_relaxed(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_add(long i, atomic_long_t *v)
-{
- return atomic64_fetch_add(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_add_acquire(long i, atomic_long_t *v)
-{
- return atomic64_fetch_add_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_add_release(long i, atomic_long_t *v)
-{
- return atomic64_fetch_add_release(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_add_relaxed(long i, atomic_long_t *v)
-{
- return atomic64_fetch_add_relaxed(i, v);
-}
-
-static __always_inline void
-atomic_long_sub(long i, atomic_long_t *v)
-{
- atomic64_sub(i, v);
-}
-
-static __always_inline long
-atomic_long_sub_return(long i, atomic_long_t *v)
-{
- return atomic64_sub_return(i, v);
-}
-
-static __always_inline long
-atomic_long_sub_return_acquire(long i, atomic_long_t *v)
-{
- return atomic64_sub_return_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_sub_return_release(long i, atomic_long_t *v)
-{
- return atomic64_sub_return_release(i, v);
-}
-
-static __always_inline long
-atomic_long_sub_return_relaxed(long i, atomic_long_t *v)
-{
- return atomic64_sub_return_relaxed(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_sub(long i, atomic_long_t *v)
-{
- return atomic64_fetch_sub(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_sub_acquire(long i, atomic_long_t *v)
-{
- return atomic64_fetch_sub_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_sub_release(long i, atomic_long_t *v)
-{
- return atomic64_fetch_sub_release(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_sub_relaxed(long i, atomic_long_t *v)
-{
- return atomic64_fetch_sub_relaxed(i, v);
-}
-
-static __always_inline void
-atomic_long_inc(atomic_long_t *v)
-{
- atomic64_inc(v);
-}
-
-static __always_inline long
-atomic_long_inc_return(atomic_long_t *v)
-{
- return atomic64_inc_return(v);
-}
-
-static __always_inline long
-atomic_long_inc_return_acquire(atomic_long_t *v)
-{
- return atomic64_inc_return_acquire(v);
-}
-
-static __always_inline long
-atomic_long_inc_return_release(atomic_long_t *v)
-{
- return atomic64_inc_return_release(v);
-}
-
-static __always_inline long
-atomic_long_inc_return_relaxed(atomic_long_t *v)
-{
- return atomic64_inc_return_relaxed(v);
-}
-
-static __always_inline long
-atomic_long_fetch_inc(atomic_long_t *v)
-{
- return atomic64_fetch_inc(v);
-}
-
-static __always_inline long
-atomic_long_fetch_inc_acquire(atomic_long_t *v)
-{
- return atomic64_fetch_inc_acquire(v);
-}
-
-static __always_inline long
-atomic_long_fetch_inc_release(atomic_long_t *v)
-{
- return atomic64_fetch_inc_release(v);
-}
-
-static __always_inline long
-atomic_long_fetch_inc_relaxed(atomic_long_t *v)
-{
- return atomic64_fetch_inc_relaxed(v);
-}
-
-static __always_inline void
-atomic_long_dec(atomic_long_t *v)
-{
- atomic64_dec(v);
-}
-
-static __always_inline long
-atomic_long_dec_return(atomic_long_t *v)
-{
- return atomic64_dec_return(v);
-}
-
-static __always_inline long
-atomic_long_dec_return_acquire(atomic_long_t *v)
-{
- return atomic64_dec_return_acquire(v);
-}
-
-static __always_inline long
-atomic_long_dec_return_release(atomic_long_t *v)
-{
- return atomic64_dec_return_release(v);
-}
-
-static __always_inline long
-atomic_long_dec_return_relaxed(atomic_long_t *v)
-{
- return atomic64_dec_return_relaxed(v);
-}
-
-static __always_inline long
-atomic_long_fetch_dec(atomic_long_t *v)
-{
- return atomic64_fetch_dec(v);
-}
-
-static __always_inline long
-atomic_long_fetch_dec_acquire(atomic_long_t *v)
-{
- return atomic64_fetch_dec_acquire(v);
-}
-
-static __always_inline long
-atomic_long_fetch_dec_release(atomic_long_t *v)
-{
- return atomic64_fetch_dec_release(v);
-}
-
-static __always_inline long
-atomic_long_fetch_dec_relaxed(atomic_long_t *v)
-{
- return atomic64_fetch_dec_relaxed(v);
-}
-
-static __always_inline void
-atomic_long_and(long i, atomic_long_t *v)
-{
- atomic64_and(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_and(long i, atomic_long_t *v)
-{
- return atomic64_fetch_and(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_and_acquire(long i, atomic_long_t *v)
-{
- return atomic64_fetch_and_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_and_release(long i, atomic_long_t *v)
-{
- return atomic64_fetch_and_release(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_and_relaxed(long i, atomic_long_t *v)
-{
- return atomic64_fetch_and_relaxed(i, v);
-}
-
-static __always_inline void
-atomic_long_andnot(long i, atomic_long_t *v)
-{
- atomic64_andnot(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_andnot(long i, atomic_long_t *v)
-{
- return atomic64_fetch_andnot(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_andnot_acquire(long i, atomic_long_t *v)
-{
- return atomic64_fetch_andnot_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_andnot_release(long i, atomic_long_t *v)
-{
- return atomic64_fetch_andnot_release(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_andnot_relaxed(long i, atomic_long_t *v)
-{
- return atomic64_fetch_andnot_relaxed(i, v);
-}
-
-static __always_inline void
-atomic_long_or(long i, atomic_long_t *v)
-{
- atomic64_or(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_or(long i, atomic_long_t *v)
-{
- return atomic64_fetch_or(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_or_acquire(long i, atomic_long_t *v)
-{
- return atomic64_fetch_or_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_or_release(long i, atomic_long_t *v)
-{
- return atomic64_fetch_or_release(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_or_relaxed(long i, atomic_long_t *v)
-{
- return atomic64_fetch_or_relaxed(i, v);
-}
-
-static __always_inline void
-atomic_long_xor(long i, atomic_long_t *v)
-{
- atomic64_xor(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_xor(long i, atomic_long_t *v)
-{
- return atomic64_fetch_xor(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_xor_acquire(long i, atomic_long_t *v)
-{
- return atomic64_fetch_xor_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_xor_release(long i, atomic_long_t *v)
-{
- return atomic64_fetch_xor_release(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_xor_relaxed(long i, atomic_long_t *v)
-{
- return atomic64_fetch_xor_relaxed(i, v);
-}
-
-static __always_inline long
-atomic_long_xchg(atomic_long_t *v, long i)
-{
- return atomic64_xchg(v, i);
-}
-
-static __always_inline long
-atomic_long_xchg_acquire(atomic_long_t *v, long i)
-{
- return atomic64_xchg_acquire(v, i);
-}
-
-static __always_inline long
-atomic_long_xchg_release(atomic_long_t *v, long i)
-{
- return atomic64_xchg_release(v, i);
-}
-
-static __always_inline long
-atomic_long_xchg_relaxed(atomic_long_t *v, long i)
-{
- return atomic64_xchg_relaxed(v, i);
-}
-
-static __always_inline long
-atomic_long_cmpxchg(atomic_long_t *v, long old, long new)
-{
- return atomic64_cmpxchg(v, old, new);
-}
-
-static __always_inline long
-atomic_long_cmpxchg_acquire(atomic_long_t *v, long old, long new)
-{
- return atomic64_cmpxchg_acquire(v, old, new);
-}
-
-static __always_inline long
-atomic_long_cmpxchg_release(atomic_long_t *v, long old, long new)
-{
- return atomic64_cmpxchg_release(v, old, new);
-}
-
-static __always_inline long
-atomic_long_cmpxchg_relaxed(atomic_long_t *v, long old, long new)
-{
- return atomic64_cmpxchg_relaxed(v, old, new);
-}
-
-static __always_inline bool
-atomic_long_try_cmpxchg(atomic_long_t *v, long *old, long new)
-{
- return atomic64_try_cmpxchg(v, (s64 *)old, new);
-}
-
-static __always_inline bool
-atomic_long_try_cmpxchg_acquire(atomic_long_t *v, long *old, long new)
-{
- return atomic64_try_cmpxchg_acquire(v, (s64 *)old, new);
-}
-
-static __always_inline bool
-atomic_long_try_cmpxchg_release(atomic_long_t *v, long *old, long new)
-{
- return atomic64_try_cmpxchg_release(v, (s64 *)old, new);
-}
-
-static __always_inline bool
-atomic_long_try_cmpxchg_relaxed(atomic_long_t *v, long *old, long new)
-{
- return atomic64_try_cmpxchg_relaxed(v, (s64 *)old, new);
-}
-
-static __always_inline bool
-atomic_long_sub_and_test(long i, atomic_long_t *v)
-{
- return atomic64_sub_and_test(i, v);
-}
-
-static __always_inline bool
-atomic_long_dec_and_test(atomic_long_t *v)
-{
- return atomic64_dec_and_test(v);
-}
-
-static __always_inline bool
-atomic_long_inc_and_test(atomic_long_t *v)
-{
- return atomic64_inc_and_test(v);
-}
-
-static __always_inline bool
-atomic_long_add_negative(long i, atomic_long_t *v)
-{
- return atomic64_add_negative(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_add_unless(atomic_long_t *v, long a, long u)
-{
- return atomic64_fetch_add_unless(v, a, u);
-}
-
-static __always_inline bool
-atomic_long_add_unless(atomic_long_t *v, long a, long u)
-{
- return atomic64_add_unless(v, a, u);
-}
-
-static __always_inline bool
-atomic_long_inc_not_zero(atomic_long_t *v)
-{
- return atomic64_inc_not_zero(v);
-}
-
-static __always_inline bool
-atomic_long_inc_unless_negative(atomic_long_t *v)
-{
- return atomic64_inc_unless_negative(v);
-}
-
-static __always_inline bool
-atomic_long_dec_unless_positive(atomic_long_t *v)
-{
- return atomic64_dec_unless_positive(v);
-}
-
-static __always_inline long
-atomic_long_dec_if_positive(atomic_long_t *v)
-{
- return atomic64_dec_if_positive(v);
-}
-
-#else /* CONFIG_64BIT */
-
-static __always_inline long
-atomic_long_read(const atomic_long_t *v)
-{
- return atomic_read(v);
-}
-
-static __always_inline long
-atomic_long_read_acquire(const atomic_long_t *v)
-{
- return atomic_read_acquire(v);
-}
-
-static __always_inline void
-atomic_long_set(atomic_long_t *v, long i)
-{
- atomic_set(v, i);
-}
-
-static __always_inline void
-atomic_long_set_release(atomic_long_t *v, long i)
-{
- atomic_set_release(v, i);
-}
-
-static __always_inline void
-atomic_long_add(long i, atomic_long_t *v)
-{
- atomic_add(i, v);
-}
-
-static __always_inline long
-atomic_long_add_return(long i, atomic_long_t *v)
-{
- return atomic_add_return(i, v);
-}
-
-static __always_inline long
-atomic_long_add_return_acquire(long i, atomic_long_t *v)
-{
- return atomic_add_return_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_add_return_release(long i, atomic_long_t *v)
-{
- return atomic_add_return_release(i, v);
-}
-
-static __always_inline long
-atomic_long_add_return_relaxed(long i, atomic_long_t *v)
-{
- return atomic_add_return_relaxed(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_add(long i, atomic_long_t *v)
-{
- return atomic_fetch_add(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_add_acquire(long i, atomic_long_t *v)
-{
- return atomic_fetch_add_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_add_release(long i, atomic_long_t *v)
-{
- return atomic_fetch_add_release(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_add_relaxed(long i, atomic_long_t *v)
-{
- return atomic_fetch_add_relaxed(i, v);
-}
-
-static __always_inline void
-atomic_long_sub(long i, atomic_long_t *v)
-{
- atomic_sub(i, v);
-}
-
-static __always_inline long
-atomic_long_sub_return(long i, atomic_long_t *v)
-{
- return atomic_sub_return(i, v);
-}
-
-static __always_inline long
-atomic_long_sub_return_acquire(long i, atomic_long_t *v)
-{
- return atomic_sub_return_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_sub_return_release(long i, atomic_long_t *v)
-{
- return atomic_sub_return_release(i, v);
-}
-
-static __always_inline long
-atomic_long_sub_return_relaxed(long i, atomic_long_t *v)
-{
- return atomic_sub_return_relaxed(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_sub(long i, atomic_long_t *v)
-{
- return atomic_fetch_sub(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_sub_acquire(long i, atomic_long_t *v)
-{
- return atomic_fetch_sub_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_sub_release(long i, atomic_long_t *v)
-{
- return atomic_fetch_sub_release(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_sub_relaxed(long i, atomic_long_t *v)
-{
- return atomic_fetch_sub_relaxed(i, v);
-}
-
-static __always_inline void
-atomic_long_inc(atomic_long_t *v)
-{
- atomic_inc(v);
-}
-
-static __always_inline long
-atomic_long_inc_return(atomic_long_t *v)
-{
- return atomic_inc_return(v);
-}
-
-static __always_inline long
-atomic_long_inc_return_acquire(atomic_long_t *v)
-{
- return atomic_inc_return_acquire(v);
-}
-
-static __always_inline long
-atomic_long_inc_return_release(atomic_long_t *v)
-{
- return atomic_inc_return_release(v);
-}
-
-static __always_inline long
-atomic_long_inc_return_relaxed(atomic_long_t *v)
-{
- return atomic_inc_return_relaxed(v);
-}
-
-static __always_inline long
-atomic_long_fetch_inc(atomic_long_t *v)
-{
- return atomic_fetch_inc(v);
-}
-
-static __always_inline long
-atomic_long_fetch_inc_acquire(atomic_long_t *v)
-{
- return atomic_fetch_inc_acquire(v);
-}
-
-static __always_inline long
-atomic_long_fetch_inc_release(atomic_long_t *v)
-{
- return atomic_fetch_inc_release(v);
-}
-
-static __always_inline long
-atomic_long_fetch_inc_relaxed(atomic_long_t *v)
-{
- return atomic_fetch_inc_relaxed(v);
-}
-
-static __always_inline void
-atomic_long_dec(atomic_long_t *v)
-{
- atomic_dec(v);
-}
-
-static __always_inline long
-atomic_long_dec_return(atomic_long_t *v)
-{
- return atomic_dec_return(v);
-}
-
-static __always_inline long
-atomic_long_dec_return_acquire(atomic_long_t *v)
-{
- return atomic_dec_return_acquire(v);
-}
-
-static __always_inline long
-atomic_long_dec_return_release(atomic_long_t *v)
-{
- return atomic_dec_return_release(v);
-}
-
-static __always_inline long
-atomic_long_dec_return_relaxed(atomic_long_t *v)
-{
- return atomic_dec_return_relaxed(v);
-}
-
-static __always_inline long
-atomic_long_fetch_dec(atomic_long_t *v)
-{
- return atomic_fetch_dec(v);
-}
-
-static __always_inline long
-atomic_long_fetch_dec_acquire(atomic_long_t *v)
-{
- return atomic_fetch_dec_acquire(v);
-}
-
-static __always_inline long
-atomic_long_fetch_dec_release(atomic_long_t *v)
-{
- return atomic_fetch_dec_release(v);
-}
-
-static __always_inline long
-atomic_long_fetch_dec_relaxed(atomic_long_t *v)
-{
- return atomic_fetch_dec_relaxed(v);
-}
-
-static __always_inline void
-atomic_long_and(long i, atomic_long_t *v)
-{
- atomic_and(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_and(long i, atomic_long_t *v)
-{
- return atomic_fetch_and(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_and_acquire(long i, atomic_long_t *v)
-{
- return atomic_fetch_and_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_and_release(long i, atomic_long_t *v)
-{
- return atomic_fetch_and_release(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_and_relaxed(long i, atomic_long_t *v)
-{
- return atomic_fetch_and_relaxed(i, v);
-}
-
-static __always_inline void
-atomic_long_andnot(long i, atomic_long_t *v)
-{
- atomic_andnot(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_andnot(long i, atomic_long_t *v)
-{
- return atomic_fetch_andnot(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_andnot_acquire(long i, atomic_long_t *v)
-{
- return atomic_fetch_andnot_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_andnot_release(long i, atomic_long_t *v)
-{
- return atomic_fetch_andnot_release(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_andnot_relaxed(long i, atomic_long_t *v)
-{
- return atomic_fetch_andnot_relaxed(i, v);
-}
-
-static __always_inline void
-atomic_long_or(long i, atomic_long_t *v)
-{
- atomic_or(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_or(long i, atomic_long_t *v)
-{
- return atomic_fetch_or(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_or_acquire(long i, atomic_long_t *v)
-{
- return atomic_fetch_or_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_or_release(long i, atomic_long_t *v)
-{
- return atomic_fetch_or_release(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_or_relaxed(long i, atomic_long_t *v)
-{
- return atomic_fetch_or_relaxed(i, v);
-}
-
-static __always_inline void
-atomic_long_xor(long i, atomic_long_t *v)
-{
- atomic_xor(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_xor(long i, atomic_long_t *v)
-{
- return atomic_fetch_xor(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_xor_acquire(long i, atomic_long_t *v)
-{
- return atomic_fetch_xor_acquire(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_xor_release(long i, atomic_long_t *v)
-{
- return atomic_fetch_xor_release(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_xor_relaxed(long i, atomic_long_t *v)
-{
- return atomic_fetch_xor_relaxed(i, v);
-}
-
-static __always_inline long
-atomic_long_xchg(atomic_long_t *v, long i)
-{
- return atomic_xchg(v, i);
-}
-
-static __always_inline long
-atomic_long_xchg_acquire(atomic_long_t *v, long i)
-{
- return atomic_xchg_acquire(v, i);
-}
-
-static __always_inline long
-atomic_long_xchg_release(atomic_long_t *v, long i)
-{
- return atomic_xchg_release(v, i);
-}
-
-static __always_inline long
-atomic_long_xchg_relaxed(atomic_long_t *v, long i)
-{
- return atomic_xchg_relaxed(v, i);
-}
-
-static __always_inline long
-atomic_long_cmpxchg(atomic_long_t *v, long old, long new)
-{
- return atomic_cmpxchg(v, old, new);
-}
-
-static __always_inline long
-atomic_long_cmpxchg_acquire(atomic_long_t *v, long old, long new)
-{
- return atomic_cmpxchg_acquire(v, old, new);
-}
-
-static __always_inline long
-atomic_long_cmpxchg_release(atomic_long_t *v, long old, long new)
-{
- return atomic_cmpxchg_release(v, old, new);
-}
-
-static __always_inline long
-atomic_long_cmpxchg_relaxed(atomic_long_t *v, long old, long new)
-{
- return atomic_cmpxchg_relaxed(v, old, new);
-}
-
-static __always_inline bool
-atomic_long_try_cmpxchg(atomic_long_t *v, long *old, long new)
-{
- return atomic_try_cmpxchg(v, (int *)old, new);
-}
-
-static __always_inline bool
-atomic_long_try_cmpxchg_acquire(atomic_long_t *v, long *old, long new)
-{
- return atomic_try_cmpxchg_acquire(v, (int *)old, new);
-}
-
-static __always_inline bool
-atomic_long_try_cmpxchg_release(atomic_long_t *v, long *old, long new)
-{
- return atomic_try_cmpxchg_release(v, (int *)old, new);
-}
-
-static __always_inline bool
-atomic_long_try_cmpxchg_relaxed(atomic_long_t *v, long *old, long new)
-{
- return atomic_try_cmpxchg_relaxed(v, (int *)old, new);
-}
-
-static __always_inline bool
-atomic_long_sub_and_test(long i, atomic_long_t *v)
-{
- return atomic_sub_and_test(i, v);
-}
-
-static __always_inline bool
-atomic_long_dec_and_test(atomic_long_t *v)
-{
- return atomic_dec_and_test(v);
-}
-
-static __always_inline bool
-atomic_long_inc_and_test(atomic_long_t *v)
-{
- return atomic_inc_and_test(v);
-}
-
-static __always_inline bool
-atomic_long_add_negative(long i, atomic_long_t *v)
-{
- return atomic_add_negative(i, v);
-}
-
-static __always_inline long
-atomic_long_fetch_add_unless(atomic_long_t *v, long a, long u)
-{
- return atomic_fetch_add_unless(v, a, u);
-}
-
-static __always_inline bool
-atomic_long_add_unless(atomic_long_t *v, long a, long u)
-{
- return atomic_add_unless(v, a, u);
-}
-
-static __always_inline bool
-atomic_long_inc_not_zero(atomic_long_t *v)
-{
- return atomic_inc_not_zero(v);
-}
-
-static __always_inline bool
-atomic_long_inc_unless_negative(atomic_long_t *v)
-{
- return atomic_inc_unless_negative(v);
-}
-
-static __always_inline bool
-atomic_long_dec_unless_positive(atomic_long_t *v)
-{
- return atomic_dec_unless_positive(v);
-}
-
-static __always_inline long
-atomic_long_dec_if_positive(atomic_long_t *v)
-{
- return atomic_dec_if_positive(v);
-}
-
-#endif /* CONFIG_64BIT */
-#endif /* _ASM_GENERIC_ATOMIC_LONG_H */
-// a624200981f552b2c6be4f32fe44da8289f30d87
diff --git a/include/asm-generic/bitops/atomic.h b/include/asm-generic/bitops/atomic.h
index 0e7316a86240..3096f086b5a3 100644
--- a/include/asm-generic/bitops/atomic.h
+++ b/include/asm-generic/bitops/atomic.h
@@ -11,25 +11,29 @@
* See Documentation/atomic_bitops.txt for details.
*/
-static __always_inline void set_bit(unsigned int nr, volatile unsigned long *p)
+static __always_inline void
+arch_set_bit(unsigned int nr, volatile unsigned long *p)
{
p += BIT_WORD(nr);
- atomic_long_or(BIT_MASK(nr), (atomic_long_t *)p);
+ arch_atomic_long_or(BIT_MASK(nr), (atomic_long_t *)p);
}
-static __always_inline void clear_bit(unsigned int nr, volatile unsigned long *p)
+static __always_inline void
+arch_clear_bit(unsigned int nr, volatile unsigned long *p)
{
p += BIT_WORD(nr);
- atomic_long_andnot(BIT_MASK(nr), (atomic_long_t *)p);
+ arch_atomic_long_andnot(BIT_MASK(nr), (atomic_long_t *)p);
}
-static __always_inline void change_bit(unsigned int nr, volatile unsigned long *p)
+static __always_inline void
+arch_change_bit(unsigned int nr, volatile unsigned long *p)
{
p += BIT_WORD(nr);
- atomic_long_xor(BIT_MASK(nr), (atomic_long_t *)p);
+ arch_atomic_long_xor(BIT_MASK(nr), (atomic_long_t *)p);
}
-static inline int test_and_set_bit(unsigned int nr, volatile unsigned long *p)
+static __always_inline int
+arch_test_and_set_bit(unsigned int nr, volatile unsigned long *p)
{
long old;
unsigned long mask = BIT_MASK(nr);
@@ -38,11 +42,12 @@ static inline int test_and_set_bit(unsigned int nr, volatile unsigned long *p)
if (READ_ONCE(*p) & mask)
return 1;
- old = atomic_long_fetch_or(mask, (atomic_long_t *)p);
+ old = arch_atomic_long_fetch_or(mask, (atomic_long_t *)p);
return !!(old & mask);
}
-static inline int test_and_clear_bit(unsigned int nr, volatile unsigned long *p)
+static __always_inline int
+arch_test_and_clear_bit(unsigned int nr, volatile unsigned long *p)
{
long old;
unsigned long mask = BIT_MASK(nr);
@@ -51,18 +56,21 @@ static inline int test_and_clear_bit(unsigned int nr, volatile unsigned long *p)
if (!(READ_ONCE(*p) & mask))
return 0;
- old = atomic_long_fetch_andnot(mask, (atomic_long_t *)p);
+ old = arch_atomic_long_fetch_andnot(mask, (atomic_long_t *)p);
return !!(old & mask);
}
-static inline int test_and_change_bit(unsigned int nr, volatile unsigned long *p)
+static __always_inline int
+arch_test_and_change_bit(unsigned int nr, volatile unsigned long *p)
{
long old;
unsigned long mask = BIT_MASK(nr);
p += BIT_WORD(nr);
- old = atomic_long_fetch_xor(mask, (atomic_long_t *)p);
+ old = arch_atomic_long_fetch_xor(mask, (atomic_long_t *)p);
return !!(old & mask);
}
+#include <asm-generic/bitops/instrumented-atomic.h>
+
#endif /* _ASM_GENERIC_BITOPS_ATOMIC_H */
diff --git a/include/asm-generic/bitops/lock.h b/include/asm-generic/bitops/lock.h
index 3ae021368f48..630f2f6b9595 100644
--- a/include/asm-generic/bitops/lock.h
+++ b/include/asm-generic/bitops/lock.h
@@ -7,7 +7,7 @@
#include <asm/barrier.h>
/**
- * test_and_set_bit_lock - Set a bit and return its old value, for lock
+ * arch_test_and_set_bit_lock - Set a bit and return its old value, for lock
* @nr: Bit to set
* @addr: Address to count from
*
@@ -15,8 +15,8 @@
* the returned value is 0.
* It can be used to implement bit locks.
*/
-static inline int test_and_set_bit_lock(unsigned int nr,
- volatile unsigned long *p)
+static __always_inline int
+arch_test_and_set_bit_lock(unsigned int nr, volatile unsigned long *p)
{
long old;
unsigned long mask = BIT_MASK(nr);
@@ -25,26 +25,27 @@ static inline int test_and_set_bit_lock(unsigned int nr,
if (READ_ONCE(*p) & mask)
return 1;
- old = atomic_long_fetch_or_acquire(mask, (atomic_long_t *)p);
+ old = arch_atomic_long_fetch_or_acquire(mask, (atomic_long_t *)p);
return !!(old & mask);
}
/**
- * clear_bit_unlock - Clear a bit in memory, for unlock
+ * arch_clear_bit_unlock - Clear a bit in memory, for unlock
* @nr: the bit to set
* @addr: the address to start counting from
*
* This operation is atomic and provides release barrier semantics.
*/
-static inline void clear_bit_unlock(unsigned int nr, volatile unsigned long *p)
+static __always_inline void
+arch_clear_bit_unlock(unsigned int nr, volatile unsigned long *p)
{
p += BIT_WORD(nr);
- atomic_long_fetch_andnot_release(BIT_MASK(nr), (atomic_long_t *)p);
+ arch_atomic_long_fetch_andnot_release(BIT_MASK(nr), (atomic_long_t *)p);
}
/**
- * __clear_bit_unlock - Clear a bit in memory, for unlock
+ * arch___clear_bit_unlock - Clear a bit in memory, for unlock
* @nr: the bit to set
* @addr: the address to start counting from
*
@@ -54,38 +55,40 @@ static inline void clear_bit_unlock(unsigned int nr, volatile unsigned long *p)
*
* See for example x86's implementation.
*/
-static inline void __clear_bit_unlock(unsigned int nr,
- volatile unsigned long *p)
+static inline void
+arch___clear_bit_unlock(unsigned int nr, volatile unsigned long *p)
{
unsigned long old;
p += BIT_WORD(nr);
old = READ_ONCE(*p);
old &= ~BIT_MASK(nr);
- atomic_long_set_release((atomic_long_t *)p, old);
+ arch_atomic_long_set_release((atomic_long_t *)p, old);
}
/**
- * clear_bit_unlock_is_negative_byte - Clear a bit in memory and test if bottom
- * byte is negative, for unlock.
+ * arch_clear_bit_unlock_is_negative_byte - Clear a bit in memory and test if bottom
+ * byte is negative, for unlock.
* @nr: the bit to clear
* @addr: the address to start counting from
*
* This is a bit of a one-trick-pony for the filemap code, which clears
* PG_locked and tests PG_waiters,
*/
-#ifndef clear_bit_unlock_is_negative_byte
-static inline bool clear_bit_unlock_is_negative_byte(unsigned int nr,
- volatile unsigned long *p)
+#ifndef arch_clear_bit_unlock_is_negative_byte
+static inline bool arch_clear_bit_unlock_is_negative_byte(unsigned int nr,
+ volatile unsigned long *p)
{
long old;
unsigned long mask = BIT_MASK(nr);
p += BIT_WORD(nr);
- old = atomic_long_fetch_andnot_release(mask, (atomic_long_t *)p);
+ old = arch_atomic_long_fetch_andnot_release(mask, (atomic_long_t *)p);
return !!(old & BIT(7));
}
-#define clear_bit_unlock_is_negative_byte clear_bit_unlock_is_negative_byte
+#define arch_clear_bit_unlock_is_negative_byte arch_clear_bit_unlock_is_negative_byte
#endif
+#include <asm-generic/bitops/instrumented-lock.h>
+
#endif /* _ASM_GENERIC_BITOPS_LOCK_H_ */
diff --git a/include/asm-generic/bitops/non-atomic.h b/include/asm-generic/bitops/non-atomic.h
index 7e10c4b50c5d..365377fb104b 100644
--- a/include/asm-generic/bitops/non-atomic.h
+++ b/include/asm-generic/bitops/non-atomic.h
@@ -5,7 +5,7 @@
#include <asm/types.h>
/**
- * __set_bit - Set a bit in memory
+ * arch___set_bit - Set a bit in memory
* @nr: the bit to set
* @addr: the address to start counting from
*
@@ -13,24 +13,28 @@
* If it's called on the same region of memory simultaneously, the effect
* may be that only one operation succeeds.
*/
-static inline void __set_bit(int nr, volatile unsigned long *addr)
+static __always_inline void
+arch___set_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
*p |= mask;
}
+#define __set_bit arch___set_bit
-static inline void __clear_bit(int nr, volatile unsigned long *addr)
+static __always_inline void
+arch___clear_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
*p &= ~mask;
}
+#define __clear_bit arch___clear_bit
/**
- * __change_bit - Toggle a bit in memory
+ * arch___change_bit - Toggle a bit in memory
* @nr: the bit to change
* @addr: the address to start counting from
*
@@ -38,16 +42,18 @@ static inline void __clear_bit(int nr, volatile unsigned long *addr)
* If it's called on the same region of memory simultaneously, the effect
* may be that only one operation succeeds.
*/
-static inline void __change_bit(int nr, volatile unsigned long *addr)
+static __always_inline
+void arch___change_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
*p ^= mask;
}
+#define __change_bit arch___change_bit
/**
- * __test_and_set_bit - Set a bit and return its old value
+ * arch___test_and_set_bit - Set a bit and return its old value
* @nr: Bit to set
* @addr: Address to count from
*
@@ -55,7 +61,8 @@ static inline void __change_bit(int nr, volatile unsigned long *addr)
* If two examples of this operation race, one can appear to succeed
* but actually fail. You must protect multiple accesses with a lock.
*/
-static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
+static __always_inline int
+arch___test_and_set_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
@@ -64,9 +71,10 @@ static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
*p = old | mask;
return (old & mask) != 0;
}
+#define __test_and_set_bit arch___test_and_set_bit
/**
- * __test_and_clear_bit - Clear a bit and return its old value
+ * arch___test_and_clear_bit - Clear a bit and return its old value
* @nr: Bit to clear
* @addr: Address to count from
*
@@ -74,7 +82,8 @@ static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
* If two examples of this operation race, one can appear to succeed
* but actually fail. You must protect multiple accesses with a lock.
*/
-static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
+static __always_inline int
+arch___test_and_clear_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
@@ -83,10 +92,11 @@ static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
*p = old & ~mask;
return (old & mask) != 0;
}
+#define __test_and_clear_bit arch___test_and_clear_bit
/* WARNING: non atomic and it can be reordered! */
-static inline int __test_and_change_bit(int nr,
- volatile unsigned long *addr)
+static __always_inline int
+arch___test_and_change_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
@@ -95,15 +105,18 @@ static inline int __test_and_change_bit(int nr,
*p = old ^ mask;
return (old & mask) != 0;
}
+#define __test_and_change_bit arch___test_and_change_bit
/**
- * test_bit - Determine whether a bit is set
+ * arch_test_bit - Determine whether a bit is set
* @nr: bit number to test
* @addr: Address to start counting from
*/
-static inline int test_bit(int nr, const volatile unsigned long *addr)
+static __always_inline int
+arch_test_bit(int nr, const volatile unsigned long *addr)
{
return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
}
+#define test_bit arch_test_bit
#endif /* _ASM_GENERIC_BITOPS_NON_ATOMIC_H_ */
diff --git a/include/linux/atomic.h b/include/linux/atomic.h
index ed1d3ffd5b9d..8dd57c3a99e9 100644
--- a/include/linux/atomic.h
+++ b/include/linux/atomic.h
@@ -77,9 +77,8 @@
__ret; \
})
-#include <linux/atomic-arch-fallback.h>
-#include <asm-generic/atomic-instrumented.h>
-
-#include <asm-generic/atomic-long.h>
+#include <linux/atomic/atomic-arch-fallback.h>
+#include <linux/atomic/atomic-long.h>
+#include <linux/atomic/atomic-instrumented.h>
#endif /* _LINUX_ATOMIC_H */
diff --git a/include/linux/atomic-arch-fallback.h b/include/linux/atomic/atomic-arch-fallback.h
index a3dba31df01e..a3dba31df01e 100644
--- a/include/linux/atomic-arch-fallback.h
+++ b/include/linux/atomic/atomic-arch-fallback.h
diff --git a/include/asm-generic/atomic-instrumented.h b/include/linux/atomic/atomic-instrumented.h
index bc45af52c93b..a0f654370da3 100644
--- a/include/asm-generic/atomic-instrumented.h
+++ b/include/linux/atomic/atomic-instrumented.h
@@ -14,8 +14,8 @@
* arch_ variants (i.e. arch_atomic_read()/arch_atomic_cmpxchg()) to avoid
* double instrumentation.
*/
-#ifndef _ASM_GENERIC_ATOMIC_INSTRUMENTED_H
-#define _ASM_GENERIC_ATOMIC_INSTRUMENTED_H
+#ifndef _LINUX_ATOMIC_INSTRUMENTED_H
+#define _LINUX_ATOMIC_INSTRUMENTED_H
#include <linux/build_bug.h>
#include <linux/compiler.h>
@@ -1177,6 +1177,584 @@ atomic64_dec_if_positive(atomic64_t *v)
return arch_atomic64_dec_if_positive(v);
}
+static __always_inline long
+atomic_long_read(const atomic_long_t *v)
+{
+ instrument_atomic_read(v, sizeof(*v));
+ return arch_atomic_long_read(v);
+}
+
+static __always_inline long
+atomic_long_read_acquire(const atomic_long_t *v)
+{
+ instrument_atomic_read(v, sizeof(*v));
+ return arch_atomic_long_read_acquire(v);
+}
+
+static __always_inline void
+atomic_long_set(atomic_long_t *v, long i)
+{
+ instrument_atomic_write(v, sizeof(*v));
+ arch_atomic_long_set(v, i);
+}
+
+static __always_inline void
+atomic_long_set_release(atomic_long_t *v, long i)
+{
+ instrument_atomic_write(v, sizeof(*v));
+ arch_atomic_long_set_release(v, i);
+}
+
+static __always_inline void
+atomic_long_add(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ arch_atomic_long_add(i, v);
+}
+
+static __always_inline long
+atomic_long_add_return(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_add_return(i, v);
+}
+
+static __always_inline long
+atomic_long_add_return_acquire(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_add_return_acquire(i, v);
+}
+
+static __always_inline long
+atomic_long_add_return_release(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_add_return_release(i, v);
+}
+
+static __always_inline long
+atomic_long_add_return_relaxed(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_add_return_relaxed(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_add(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_add(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_add_acquire(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_add_acquire(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_add_release(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_add_release(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_add_relaxed(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_add_relaxed(i, v);
+}
+
+static __always_inline void
+atomic_long_sub(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ arch_atomic_long_sub(i, v);
+}
+
+static __always_inline long
+atomic_long_sub_return(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_sub_return(i, v);
+}
+
+static __always_inline long
+atomic_long_sub_return_acquire(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_sub_return_acquire(i, v);
+}
+
+static __always_inline long
+atomic_long_sub_return_release(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_sub_return_release(i, v);
+}
+
+static __always_inline long
+atomic_long_sub_return_relaxed(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_sub_return_relaxed(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_sub(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_sub(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_sub_acquire(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_sub_acquire(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_sub_release(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_sub_release(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_sub_relaxed(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_sub_relaxed(i, v);
+}
+
+static __always_inline void
+atomic_long_inc(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ arch_atomic_long_inc(v);
+}
+
+static __always_inline long
+atomic_long_inc_return(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_inc_return(v);
+}
+
+static __always_inline long
+atomic_long_inc_return_acquire(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_inc_return_acquire(v);
+}
+
+static __always_inline long
+atomic_long_inc_return_release(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_inc_return_release(v);
+}
+
+static __always_inline long
+atomic_long_inc_return_relaxed(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_inc_return_relaxed(v);
+}
+
+static __always_inline long
+atomic_long_fetch_inc(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_inc(v);
+}
+
+static __always_inline long
+atomic_long_fetch_inc_acquire(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_inc_acquire(v);
+}
+
+static __always_inline long
+atomic_long_fetch_inc_release(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_inc_release(v);
+}
+
+static __always_inline long
+atomic_long_fetch_inc_relaxed(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_inc_relaxed(v);
+}
+
+static __always_inline void
+atomic_long_dec(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ arch_atomic_long_dec(v);
+}
+
+static __always_inline long
+atomic_long_dec_return(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_dec_return(v);
+}
+
+static __always_inline long
+atomic_long_dec_return_acquire(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_dec_return_acquire(v);
+}
+
+static __always_inline long
+atomic_long_dec_return_release(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_dec_return_release(v);
+}
+
+static __always_inline long
+atomic_long_dec_return_relaxed(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_dec_return_relaxed(v);
+}
+
+static __always_inline long
+atomic_long_fetch_dec(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_dec(v);
+}
+
+static __always_inline long
+atomic_long_fetch_dec_acquire(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_dec_acquire(v);
+}
+
+static __always_inline long
+atomic_long_fetch_dec_release(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_dec_release(v);
+}
+
+static __always_inline long
+atomic_long_fetch_dec_relaxed(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_dec_relaxed(v);
+}
+
+static __always_inline void
+atomic_long_and(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ arch_atomic_long_and(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_and(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_and(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_and_acquire(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_and_acquire(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_and_release(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_and_release(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_and_relaxed(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_and_relaxed(i, v);
+}
+
+static __always_inline void
+atomic_long_andnot(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ arch_atomic_long_andnot(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_andnot(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_andnot(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_andnot_acquire(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_andnot_acquire(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_andnot_release(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_andnot_release(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_andnot_relaxed(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_andnot_relaxed(i, v);
+}
+
+static __always_inline void
+atomic_long_or(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ arch_atomic_long_or(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_or(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_or(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_or_acquire(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_or_acquire(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_or_release(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_or_release(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_or_relaxed(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_or_relaxed(i, v);
+}
+
+static __always_inline void
+atomic_long_xor(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ arch_atomic_long_xor(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_xor(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_xor(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_xor_acquire(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_xor_acquire(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_xor_release(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_xor_release(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_xor_relaxed(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_xor_relaxed(i, v);
+}
+
+static __always_inline long
+atomic_long_xchg(atomic_long_t *v, long i)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_xchg(v, i);
+}
+
+static __always_inline long
+atomic_long_xchg_acquire(atomic_long_t *v, long i)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_xchg_acquire(v, i);
+}
+
+static __always_inline long
+atomic_long_xchg_release(atomic_long_t *v, long i)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_xchg_release(v, i);
+}
+
+static __always_inline long
+atomic_long_xchg_relaxed(atomic_long_t *v, long i)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_xchg_relaxed(v, i);
+}
+
+static __always_inline long
+atomic_long_cmpxchg(atomic_long_t *v, long old, long new)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_cmpxchg(v, old, new);
+}
+
+static __always_inline long
+atomic_long_cmpxchg_acquire(atomic_long_t *v, long old, long new)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_cmpxchg_acquire(v, old, new);
+}
+
+static __always_inline long
+atomic_long_cmpxchg_release(atomic_long_t *v, long old, long new)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_cmpxchg_release(v, old, new);
+}
+
+static __always_inline long
+atomic_long_cmpxchg_relaxed(atomic_long_t *v, long old, long new)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_cmpxchg_relaxed(v, old, new);
+}
+
+static __always_inline bool
+atomic_long_try_cmpxchg(atomic_long_t *v, long *old, long new)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ instrument_atomic_read_write(old, sizeof(*old));
+ return arch_atomic_long_try_cmpxchg(v, old, new);
+}
+
+static __always_inline bool
+atomic_long_try_cmpxchg_acquire(atomic_long_t *v, long *old, long new)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ instrument_atomic_read_write(old, sizeof(*old));
+ return arch_atomic_long_try_cmpxchg_acquire(v, old, new);
+}
+
+static __always_inline bool
+atomic_long_try_cmpxchg_release(atomic_long_t *v, long *old, long new)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ instrument_atomic_read_write(old, sizeof(*old));
+ return arch_atomic_long_try_cmpxchg_release(v, old, new);
+}
+
+static __always_inline bool
+atomic_long_try_cmpxchg_relaxed(atomic_long_t *v, long *old, long new)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ instrument_atomic_read_write(old, sizeof(*old));
+ return arch_atomic_long_try_cmpxchg_relaxed(v, old, new);
+}
+
+static __always_inline bool
+atomic_long_sub_and_test(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_sub_and_test(i, v);
+}
+
+static __always_inline bool
+atomic_long_dec_and_test(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_dec_and_test(v);
+}
+
+static __always_inline bool
+atomic_long_inc_and_test(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_inc_and_test(v);
+}
+
+static __always_inline bool
+atomic_long_add_negative(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_add_negative(i, v);
+}
+
+static __always_inline long
+atomic_long_fetch_add_unless(atomic_long_t *v, long a, long u)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_fetch_add_unless(v, a, u);
+}
+
+static __always_inline bool
+atomic_long_add_unless(atomic_long_t *v, long a, long u)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_add_unless(v, a, u);
+}
+
+static __always_inline bool
+atomic_long_inc_not_zero(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_inc_not_zero(v);
+}
+
+static __always_inline bool
+atomic_long_inc_unless_negative(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_inc_unless_negative(v);
+}
+
+static __always_inline bool
+atomic_long_dec_unless_positive(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_dec_unless_positive(v);
+}
+
+static __always_inline long
+atomic_long_dec_if_positive(atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_dec_if_positive(v);
+}
+
#define xchg(ptr, ...) \
({ \
typeof(ptr) __ai_ptr = (ptr); \
@@ -1333,5 +1911,5 @@ atomic64_dec_if_positive(atomic64_t *v)
arch_cmpxchg_double_local(__ai_ptr, __VA_ARGS__); \
})
-#endif /* _ASM_GENERIC_ATOMIC_INSTRUMENTED_H */
-// 1d7c3a25aca5c7fb031c307be4c3d24c7b48fcd5
+#endif /* _LINUX_ATOMIC_INSTRUMENTED_H */
+// 2a9553f0a9d5619f19151092df5cabbbf16ce835
diff --git a/include/linux/atomic/atomic-long.h b/include/linux/atomic/atomic-long.h
new file mode 100644
index 000000000000..800b8c35992d
--- /dev/null
+++ b/include/linux/atomic/atomic-long.h
@@ -0,0 +1,1014 @@
+// SPDX-License-Identifier: GPL-2.0
+
+// Generated by scripts/atomic/gen-atomic-long.sh
+// DO NOT MODIFY THIS FILE DIRECTLY
+
+#ifndef _LINUX_ATOMIC_LONG_H
+#define _LINUX_ATOMIC_LONG_H
+
+#include <linux/compiler.h>
+#include <asm/types.h>
+
+#ifdef CONFIG_64BIT
+typedef atomic64_t atomic_long_t;
+#define ATOMIC_LONG_INIT(i) ATOMIC64_INIT(i)
+#define atomic_long_cond_read_acquire atomic64_cond_read_acquire
+#define atomic_long_cond_read_relaxed atomic64_cond_read_relaxed
+#else
+typedef atomic_t atomic_long_t;
+#define ATOMIC_LONG_INIT(i) ATOMIC_INIT(i)
+#define atomic_long_cond_read_acquire atomic_cond_read_acquire
+#define atomic_long_cond_read_relaxed atomic_cond_read_relaxed
+#endif
+
+#ifdef CONFIG_64BIT
+
+static __always_inline long
+arch_atomic_long_read(const atomic_long_t *v)
+{
+ return arch_atomic64_read(v);
+}
+
+static __always_inline long
+arch_atomic_long_read_acquire(const atomic_long_t *v)
+{
+ return arch_atomic64_read_acquire(v);
+}
+
+static __always_inline void
+arch_atomic_long_set(atomic_long_t *v, long i)
+{
+ arch_atomic64_set(v, i);
+}
+
+static __always_inline void
+arch_atomic_long_set_release(atomic_long_t *v, long i)
+{
+ arch_atomic64_set_release(v, i);
+}
+
+static __always_inline void
+arch_atomic_long_add(long i, atomic_long_t *v)
+{
+ arch_atomic64_add(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_add_return(long i, atomic_long_t *v)
+{
+ return arch_atomic64_add_return(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_add_return_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic64_add_return_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_add_return_release(long i, atomic_long_t *v)
+{
+ return arch_atomic64_add_return_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_add_return_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic64_add_return_relaxed(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_add(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_add(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_add_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_add_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_add_release(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_add_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_add_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_add_relaxed(i, v);
+}
+
+static __always_inline void
+arch_atomic_long_sub(long i, atomic_long_t *v)
+{
+ arch_atomic64_sub(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_sub_return(long i, atomic_long_t *v)
+{
+ return arch_atomic64_sub_return(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_sub_return_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic64_sub_return_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_sub_return_release(long i, atomic_long_t *v)
+{
+ return arch_atomic64_sub_return_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_sub_return_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic64_sub_return_relaxed(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_sub(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_sub(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_sub_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_sub_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_sub_release(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_sub_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_sub_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_sub_relaxed(i, v);
+}
+
+static __always_inline void
+arch_atomic_long_inc(atomic_long_t *v)
+{
+ arch_atomic64_inc(v);
+}
+
+static __always_inline long
+arch_atomic_long_inc_return(atomic_long_t *v)
+{
+ return arch_atomic64_inc_return(v);
+}
+
+static __always_inline long
+arch_atomic_long_inc_return_acquire(atomic_long_t *v)
+{
+ return arch_atomic64_inc_return_acquire(v);
+}
+
+static __always_inline long
+arch_atomic_long_inc_return_release(atomic_long_t *v)
+{
+ return arch_atomic64_inc_return_release(v);
+}
+
+static __always_inline long
+arch_atomic_long_inc_return_relaxed(atomic_long_t *v)
+{
+ return arch_atomic64_inc_return_relaxed(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_inc(atomic_long_t *v)
+{
+ return arch_atomic64_fetch_inc(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_inc_acquire(atomic_long_t *v)
+{
+ return arch_atomic64_fetch_inc_acquire(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_inc_release(atomic_long_t *v)
+{
+ return arch_atomic64_fetch_inc_release(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_inc_relaxed(atomic_long_t *v)
+{
+ return arch_atomic64_fetch_inc_relaxed(v);
+}
+
+static __always_inline void
+arch_atomic_long_dec(atomic_long_t *v)
+{
+ arch_atomic64_dec(v);
+}
+
+static __always_inline long
+arch_atomic_long_dec_return(atomic_long_t *v)
+{
+ return arch_atomic64_dec_return(v);
+}
+
+static __always_inline long
+arch_atomic_long_dec_return_acquire(atomic_long_t *v)
+{
+ return arch_atomic64_dec_return_acquire(v);
+}
+
+static __always_inline long
+arch_atomic_long_dec_return_release(atomic_long_t *v)
+{
+ return arch_atomic64_dec_return_release(v);
+}
+
+static __always_inline long
+arch_atomic_long_dec_return_relaxed(atomic_long_t *v)
+{
+ return arch_atomic64_dec_return_relaxed(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_dec(atomic_long_t *v)
+{
+ return arch_atomic64_fetch_dec(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_dec_acquire(atomic_long_t *v)
+{
+ return arch_atomic64_fetch_dec_acquire(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_dec_release(atomic_long_t *v)
+{
+ return arch_atomic64_fetch_dec_release(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_dec_relaxed(atomic_long_t *v)
+{
+ return arch_atomic64_fetch_dec_relaxed(v);
+}
+
+static __always_inline void
+arch_atomic_long_and(long i, atomic_long_t *v)
+{
+ arch_atomic64_and(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_and(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_and(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_and_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_and_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_and_release(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_and_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_and_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_and_relaxed(i, v);
+}
+
+static __always_inline void
+arch_atomic_long_andnot(long i, atomic_long_t *v)
+{
+ arch_atomic64_andnot(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_andnot(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_andnot(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_andnot_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_andnot_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_andnot_release(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_andnot_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_andnot_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_andnot_relaxed(i, v);
+}
+
+static __always_inline void
+arch_atomic_long_or(long i, atomic_long_t *v)
+{
+ arch_atomic64_or(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_or(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_or(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_or_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_or_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_or_release(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_or_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_or_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_or_relaxed(i, v);
+}
+
+static __always_inline void
+arch_atomic_long_xor(long i, atomic_long_t *v)
+{
+ arch_atomic64_xor(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_xor(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_xor(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_xor_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_xor_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_xor_release(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_xor_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_xor_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic64_fetch_xor_relaxed(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_xchg(atomic_long_t *v, long i)
+{
+ return arch_atomic64_xchg(v, i);
+}
+
+static __always_inline long
+arch_atomic_long_xchg_acquire(atomic_long_t *v, long i)
+{
+ return arch_atomic64_xchg_acquire(v, i);
+}
+
+static __always_inline long
+arch_atomic_long_xchg_release(atomic_long_t *v, long i)
+{
+ return arch_atomic64_xchg_release(v, i);
+}
+
+static __always_inline long
+arch_atomic_long_xchg_relaxed(atomic_long_t *v, long i)
+{
+ return arch_atomic64_xchg_relaxed(v, i);
+}
+
+static __always_inline long
+arch_atomic_long_cmpxchg(atomic_long_t *v, long old, long new)
+{
+ return arch_atomic64_cmpxchg(v, old, new);
+}
+
+static __always_inline long
+arch_atomic_long_cmpxchg_acquire(atomic_long_t *v, long old, long new)
+{
+ return arch_atomic64_cmpxchg_acquire(v, old, new);
+}
+
+static __always_inline long
+arch_atomic_long_cmpxchg_release(atomic_long_t *v, long old, long new)
+{
+ return arch_atomic64_cmpxchg_release(v, old, new);
+}
+
+static __always_inline long
+arch_atomic_long_cmpxchg_relaxed(atomic_long_t *v, long old, long new)
+{
+ return arch_atomic64_cmpxchg_relaxed(v, old, new);
+}
+
+static __always_inline bool
+arch_atomic_long_try_cmpxchg(atomic_long_t *v, long *old, long new)
+{
+ return arch_atomic64_try_cmpxchg(v, (s64 *)old, new);
+}
+
+static __always_inline bool
+arch_atomic_long_try_cmpxchg_acquire(atomic_long_t *v, long *old, long new)
+{
+ return arch_atomic64_try_cmpxchg_acquire(v, (s64 *)old, new);
+}
+
+static __always_inline bool
+arch_atomic_long_try_cmpxchg_release(atomic_long_t *v, long *old, long new)
+{
+ return arch_atomic64_try_cmpxchg_release(v, (s64 *)old, new);
+}
+
+static __always_inline bool
+arch_atomic_long_try_cmpxchg_relaxed(atomic_long_t *v, long *old, long new)
+{
+ return arch_atomic64_try_cmpxchg_relaxed(v, (s64 *)old, new);
+}
+
+static __always_inline bool
+arch_atomic_long_sub_and_test(long i, atomic_long_t *v)
+{
+ return arch_atomic64_sub_and_test(i, v);
+}
+
+static __always_inline bool
+arch_atomic_long_dec_and_test(atomic_long_t *v)
+{
+ return arch_atomic64_dec_and_test(v);
+}
+
+static __always_inline bool
+arch_atomic_long_inc_and_test(atomic_long_t *v)
+{
+ return arch_atomic64_inc_and_test(v);
+}
+
+static __always_inline bool
+arch_atomic_long_add_negative(long i, atomic_long_t *v)
+{
+ return arch_atomic64_add_negative(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_add_unless(atomic_long_t *v, long a, long u)
+{
+ return arch_atomic64_fetch_add_unless(v, a, u);
+}
+
+static __always_inline bool
+arch_atomic_long_add_unless(atomic_long_t *v, long a, long u)
+{
+ return arch_atomic64_add_unless(v, a, u);
+}
+
+static __always_inline bool
+arch_atomic_long_inc_not_zero(atomic_long_t *v)
+{
+ return arch_atomic64_inc_not_zero(v);
+}
+
+static __always_inline bool
+arch_atomic_long_inc_unless_negative(atomic_long_t *v)
+{
+ return arch_atomic64_inc_unless_negative(v);
+}
+
+static __always_inline bool
+arch_atomic_long_dec_unless_positive(atomic_long_t *v)
+{
+ return arch_atomic64_dec_unless_positive(v);
+}
+
+static __always_inline long
+arch_atomic_long_dec_if_positive(atomic_long_t *v)
+{
+ return arch_atomic64_dec_if_positive(v);
+}
+
+#else /* CONFIG_64BIT */
+
+static __always_inline long
+arch_atomic_long_read(const atomic_long_t *v)
+{
+ return arch_atomic_read(v);
+}
+
+static __always_inline long
+arch_atomic_long_read_acquire(const atomic_long_t *v)
+{
+ return arch_atomic_read_acquire(v);
+}
+
+static __always_inline void
+arch_atomic_long_set(atomic_long_t *v, long i)
+{
+ arch_atomic_set(v, i);
+}
+
+static __always_inline void
+arch_atomic_long_set_release(atomic_long_t *v, long i)
+{
+ arch_atomic_set_release(v, i);
+}
+
+static __always_inline void
+arch_atomic_long_add(long i, atomic_long_t *v)
+{
+ arch_atomic_add(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_add_return(long i, atomic_long_t *v)
+{
+ return arch_atomic_add_return(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_add_return_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic_add_return_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_add_return_release(long i, atomic_long_t *v)
+{
+ return arch_atomic_add_return_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_add_return_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic_add_return_relaxed(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_add(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_add(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_add_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_add_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_add_release(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_add_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_add_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_add_relaxed(i, v);
+}
+
+static __always_inline void
+arch_atomic_long_sub(long i, atomic_long_t *v)
+{
+ arch_atomic_sub(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_sub_return(long i, atomic_long_t *v)
+{
+ return arch_atomic_sub_return(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_sub_return_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic_sub_return_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_sub_return_release(long i, atomic_long_t *v)
+{
+ return arch_atomic_sub_return_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_sub_return_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic_sub_return_relaxed(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_sub(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_sub(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_sub_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_sub_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_sub_release(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_sub_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_sub_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_sub_relaxed(i, v);
+}
+
+static __always_inline void
+arch_atomic_long_inc(atomic_long_t *v)
+{
+ arch_atomic_inc(v);
+}
+
+static __always_inline long
+arch_atomic_long_inc_return(atomic_long_t *v)
+{
+ return arch_atomic_inc_return(v);
+}
+
+static __always_inline long
+arch_atomic_long_inc_return_acquire(atomic_long_t *v)
+{
+ return arch_atomic_inc_return_acquire(v);
+}
+
+static __always_inline long
+arch_atomic_long_inc_return_release(atomic_long_t *v)
+{
+ return arch_atomic_inc_return_release(v);
+}
+
+static __always_inline long
+arch_atomic_long_inc_return_relaxed(atomic_long_t *v)
+{
+ return arch_atomic_inc_return_relaxed(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_inc(atomic_long_t *v)
+{
+ return arch_atomic_fetch_inc(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_inc_acquire(atomic_long_t *v)
+{
+ return arch_atomic_fetch_inc_acquire(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_inc_release(atomic_long_t *v)
+{
+ return arch_atomic_fetch_inc_release(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_inc_relaxed(atomic_long_t *v)
+{
+ return arch_atomic_fetch_inc_relaxed(v);
+}
+
+static __always_inline void
+arch_atomic_long_dec(atomic_long_t *v)
+{
+ arch_atomic_dec(v);
+}
+
+static __always_inline long
+arch_atomic_long_dec_return(atomic_long_t *v)
+{
+ return arch_atomic_dec_return(v);
+}
+
+static __always_inline long
+arch_atomic_long_dec_return_acquire(atomic_long_t *v)
+{
+ return arch_atomic_dec_return_acquire(v);
+}
+
+static __always_inline long
+arch_atomic_long_dec_return_release(atomic_long_t *v)
+{
+ return arch_atomic_dec_return_release(v);
+}
+
+static __always_inline long
+arch_atomic_long_dec_return_relaxed(atomic_long_t *v)
+{
+ return arch_atomic_dec_return_relaxed(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_dec(atomic_long_t *v)
+{
+ return arch_atomic_fetch_dec(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_dec_acquire(atomic_long_t *v)
+{
+ return arch_atomic_fetch_dec_acquire(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_dec_release(atomic_long_t *v)
+{
+ return arch_atomic_fetch_dec_release(v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_dec_relaxed(atomic_long_t *v)
+{
+ return arch_atomic_fetch_dec_relaxed(v);
+}
+
+static __always_inline void
+arch_atomic_long_and(long i, atomic_long_t *v)
+{
+ arch_atomic_and(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_and(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_and(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_and_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_and_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_and_release(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_and_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_and_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_and_relaxed(i, v);
+}
+
+static __always_inline void
+arch_atomic_long_andnot(long i, atomic_long_t *v)
+{
+ arch_atomic_andnot(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_andnot(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_andnot(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_andnot_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_andnot_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_andnot_release(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_andnot_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_andnot_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_andnot_relaxed(i, v);
+}
+
+static __always_inline void
+arch_atomic_long_or(long i, atomic_long_t *v)
+{
+ arch_atomic_or(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_or(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_or(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_or_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_or_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_or_release(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_or_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_or_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_or_relaxed(i, v);
+}
+
+static __always_inline void
+arch_atomic_long_xor(long i, atomic_long_t *v)
+{
+ arch_atomic_xor(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_xor(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_xor(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_xor_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_xor_acquire(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_xor_release(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_xor_release(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_xor_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic_fetch_xor_relaxed(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_xchg(atomic_long_t *v, long i)
+{
+ return arch_atomic_xchg(v, i);
+}
+
+static __always_inline long
+arch_atomic_long_xchg_acquire(atomic_long_t *v, long i)
+{
+ return arch_atomic_xchg_acquire(v, i);
+}
+
+static __always_inline long
+arch_atomic_long_xchg_release(atomic_long_t *v, long i)
+{
+ return arch_atomic_xchg_release(v, i);
+}
+
+static __always_inline long
+arch_atomic_long_xchg_relaxed(atomic_long_t *v, long i)
+{
+ return arch_atomic_xchg_relaxed(v, i);
+}
+
+static __always_inline long
+arch_atomic_long_cmpxchg(atomic_long_t *v, long old, long new)
+{
+ return arch_atomic_cmpxchg(v, old, new);
+}
+
+static __always_inline long
+arch_atomic_long_cmpxchg_acquire(atomic_long_t *v, long old, long new)
+{
+ return arch_atomic_cmpxchg_acquire(v, old, new);
+}
+
+static __always_inline long
+arch_atomic_long_cmpxchg_release(atomic_long_t *v, long old, long new)
+{
+ return arch_atomic_cmpxchg_release(v, old, new);
+}
+
+static __always_inline long
+arch_atomic_long_cmpxchg_relaxed(atomic_long_t *v, long old, long new)
+{
+ return arch_atomic_cmpxchg_relaxed(v, old, new);
+}
+
+static __always_inline bool
+arch_atomic_long_try_cmpxchg(atomic_long_t *v, long *old, long new)
+{
+ return arch_atomic_try_cmpxchg(v, (int *)old, new);
+}
+
+static __always_inline bool
+arch_atomic_long_try_cmpxchg_acquire(atomic_long_t *v, long *old, long new)
+{
+ return arch_atomic_try_cmpxchg_acquire(v, (int *)old, new);
+}
+
+static __always_inline bool
+arch_atomic_long_try_cmpxchg_release(atomic_long_t *v, long *old, long new)
+{
+ return arch_atomic_try_cmpxchg_release(v, (int *)old, new);
+}
+
+static __always_inline bool
+arch_atomic_long_try_cmpxchg_relaxed(atomic_long_t *v, long *old, long new)
+{
+ return arch_atomic_try_cmpxchg_relaxed(v, (int *)old, new);
+}
+
+static __always_inline bool
+arch_atomic_long_sub_and_test(long i, atomic_long_t *v)
+{
+ return arch_atomic_sub_and_test(i, v);
+}
+
+static __always_inline bool
+arch_atomic_long_dec_and_test(atomic_long_t *v)
+{
+ return arch_atomic_dec_and_test(v);
+}
+
+static __always_inline bool
+arch_atomic_long_inc_and_test(atomic_long_t *v)
+{
+ return arch_atomic_inc_and_test(v);
+}
+
+static __always_inline bool
+arch_atomic_long_add_negative(long i, atomic_long_t *v)
+{
+ return arch_atomic_add_negative(i, v);
+}
+
+static __always_inline long
+arch_atomic_long_fetch_add_unless(atomic_long_t *v, long a, long u)
+{
+ return arch_atomic_fetch_add_unless(v, a, u);
+}
+
+static __always_inline bool
+arch_atomic_long_add_unless(atomic_long_t *v, long a, long u)
+{
+ return arch_atomic_add_unless(v, a, u);
+}
+
+static __always_inline bool
+arch_atomic_long_inc_not_zero(atomic_long_t *v)
+{
+ return arch_atomic_inc_not_zero(v);
+}
+
+static __always_inline bool
+arch_atomic_long_inc_unless_negative(atomic_long_t *v)
+{
+ return arch_atomic_inc_unless_negative(v);
+}
+
+static __always_inline bool
+arch_atomic_long_dec_unless_positive(atomic_long_t *v)
+{
+ return arch_atomic_dec_unless_positive(v);
+}
+
+static __always_inline long
+arch_atomic_long_dec_if_positive(atomic_long_t *v)
+{
+ return arch_atomic_dec_if_positive(v);
+}
+
+#endif /* CONFIG_64BIT */
+#endif /* _LINUX_ATOMIC_LONG_H */
+// e8f0e08ff072b74d180eabe2ad001282b38c2c88
diff --git a/include/linux/debug_locks.h b/include/linux/debug_locks.h
index edb5c186b0b7..3f49e65169c6 100644
--- a/include/linux/debug_locks.h
+++ b/include/linux/debug_locks.h
@@ -3,8 +3,7 @@
#define __LINUX_DEBUG_LOCKING_H
#include <linux/atomic.h>
-#include <linux/bug.h>
-#include <linux/printk.h>
+#include <linux/cache.h>
struct task_struct;
diff --git a/include/linux/local_lock_internal.h b/include/linux/local_lock_internal.h
index ded90b097e6e..975e33b793a7 100644
--- a/include/linux/local_lock_internal.h
+++ b/include/linux/local_lock_internal.h
@@ -6,6 +6,8 @@
#include <linux/percpu-defs.h>
#include <linux/lockdep.h>
+#ifndef CONFIG_PREEMPT_RT
+
typedef struct {
#ifdef CONFIG_DEBUG_LOCK_ALLOC
struct lockdep_map dep_map;
@@ -14,29 +16,14 @@ typedef struct {
} local_lock_t;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define LL_DEP_MAP_INIT(lockname) \
+# define LOCAL_LOCK_DEBUG_INIT(lockname) \
.dep_map = { \
.name = #lockname, \
.wait_type_inner = LD_WAIT_CONFIG, \
- .lock_type = LD_LOCK_PERCPU, \
- }
-#else
-# define LL_DEP_MAP_INIT(lockname)
-#endif
-
-#define INIT_LOCAL_LOCK(lockname) { LL_DEP_MAP_INIT(lockname) }
-
-#define __local_lock_init(lock) \
-do { \
- static struct lock_class_key __key; \
- \
- debug_check_no_locks_freed((void *)lock, sizeof(*lock));\
- lockdep_init_map_type(&(lock)->dep_map, #lock, &__key, 0, \
- LD_WAIT_CONFIG, LD_WAIT_INV, \
- LD_LOCK_PERCPU); \
-} while (0)
+ .lock_type = LD_LOCK_PERCPU, \
+ }, \
+ .owner = NULL,
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
static inline void local_lock_acquire(local_lock_t *l)
{
lock_map_acquire(&l->dep_map);
@@ -51,11 +38,30 @@ static inline void local_lock_release(local_lock_t *l)
lock_map_release(&l->dep_map);
}
+static inline void local_lock_debug_init(local_lock_t *l)
+{
+ l->owner = NULL;
+}
#else /* CONFIG_DEBUG_LOCK_ALLOC */
+# define LOCAL_LOCK_DEBUG_INIT(lockname)
static inline void local_lock_acquire(local_lock_t *l) { }
static inline void local_lock_release(local_lock_t *l) { }
+static inline void local_lock_debug_init(local_lock_t *l) { }
#endif /* !CONFIG_DEBUG_LOCK_ALLOC */
+#define INIT_LOCAL_LOCK(lockname) { LOCAL_LOCK_DEBUG_INIT(lockname) }
+
+#define __local_lock_init(lock) \
+do { \
+ static struct lock_class_key __key; \
+ \
+ debug_check_no_locks_freed((void *)lock, sizeof(*lock));\
+ lockdep_init_map_type(&(lock)->dep_map, #lock, &__key, \
+ 0, LD_WAIT_CONFIG, LD_WAIT_INV, \
+ LD_LOCK_PERCPU); \
+ local_lock_debug_init(lock); \
+} while (0)
+
#define __local_lock(lock) \
do { \
preempt_disable(); \
@@ -91,3 +97,45 @@ static inline void local_lock_release(local_lock_t *l) { }
local_lock_release(this_cpu_ptr(lock)); \
local_irq_restore(flags); \
} while (0)
+
+#else /* !CONFIG_PREEMPT_RT */
+
+/*
+ * On PREEMPT_RT local_lock maps to a per CPU spinlock, which protects the
+ * critical section while staying preemptible.
+ */
+typedef spinlock_t local_lock_t;
+
+#define INIT_LOCAL_LOCK(lockname) __LOCAL_SPIN_LOCK_UNLOCKED((lockname))
+
+#define __local_lock_init(l) \
+ do { \
+ local_spin_lock_init((l)); \
+ } while (0)
+
+#define __local_lock(__lock) \
+ do { \
+ migrate_disable(); \
+ spin_lock(this_cpu_ptr((__lock))); \
+ } while (0)
+
+#define __local_lock_irq(lock) __local_lock(lock)
+
+#define __local_lock_irqsave(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ flags = 0; \
+ __local_lock(lock); \
+ } while (0)
+
+#define __local_unlock(__lock) \
+ do { \
+ spin_unlock(this_cpu_ptr((__lock))); \
+ migrate_enable(); \
+ } while (0)
+
+#define __local_unlock_irq(lock) __local_unlock(lock)
+
+#define __local_unlock_irqrestore(lock, flags) __local_unlock(lock)
+
+#endif /* CONFIG_PREEMPT_RT */
diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index e19323521f9c..8f226d460f51 100644
--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -20,8 +20,17 @@
#include <linux/osq_lock.h>
#include <linux/debug_locks.h>
-struct ww_class;
-struct ww_acquire_ctx;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \
+ , .dep_map = { \
+ .name = #lockname, \
+ .wait_type_inner = LD_WAIT_SLEEP, \
+ }
+#else
+# define __DEP_MAP_MUTEX_INITIALIZER(lockname)
+#endif
+
+#ifndef CONFIG_PREEMPT_RT
/*
* Simple, straightforward mutexes with strict semantics:
@@ -53,7 +62,7 @@ struct ww_acquire_ctx;
*/
struct mutex {
atomic_long_t owner;
- spinlock_t wait_lock;
+ raw_spinlock_t wait_lock;
#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
struct optimistic_spin_queue osq; /* Spinner MCS lock */
#endif
@@ -66,27 +75,6 @@ struct mutex {
#endif
};
-struct ww_mutex {
- struct mutex base;
- struct ww_acquire_ctx *ctx;
-#ifdef CONFIG_DEBUG_MUTEXES
- struct ww_class *ww_class;
-#endif
-};
-
-/*
- * This is the control structure for tasks blocked on mutex,
- * which resides on the blocked task's kernel stack:
- */
-struct mutex_waiter {
- struct list_head list;
- struct task_struct *task;
- struct ww_acquire_ctx *ww_ctx;
-#ifdef CONFIG_DEBUG_MUTEXES
- void *magic;
-#endif
-};
-
#ifdef CONFIG_DEBUG_MUTEXES
#define __DEBUG_MUTEX_INITIALIZER(lockname) \
@@ -117,19 +105,9 @@ do { \
__mutex_init((mutex), #mutex, &__key); \
} while (0)
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \
- , .dep_map = { \
- .name = #lockname, \
- .wait_type_inner = LD_WAIT_SLEEP, \
- }
-#else
-# define __DEP_MAP_MUTEX_INITIALIZER(lockname)
-#endif
-
#define __MUTEX_INITIALIZER(lockname) \
{ .owner = ATOMIC_LONG_INIT(0) \
- , .wait_lock = __SPIN_LOCK_UNLOCKED(lockname.wait_lock) \
+ , .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(lockname.wait_lock) \
, .wait_list = LIST_HEAD_INIT(lockname.wait_list) \
__DEBUG_MUTEX_INITIALIZER(lockname) \
__DEP_MAP_MUTEX_INITIALIZER(lockname) }
@@ -148,6 +126,50 @@ extern void __mutex_init(struct mutex *lock, const char *name,
*/
extern bool mutex_is_locked(struct mutex *lock);
+#else /* !CONFIG_PREEMPT_RT */
+/*
+ * Preempt-RT variant based on rtmutexes.
+ */
+#include <linux/rtmutex.h>
+
+struct mutex {
+ struct rt_mutex_base rtmutex;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
+};
+
+#define __MUTEX_INITIALIZER(mutexname) \
+{ \
+ .rtmutex = __RT_MUTEX_BASE_INITIALIZER(mutexname.rtmutex) \
+ __DEP_MAP_MUTEX_INITIALIZER(mutexname) \
+}
+
+#define DEFINE_MUTEX(mutexname) \
+ struct mutex mutexname = __MUTEX_INITIALIZER(mutexname)
+
+extern void __mutex_rt_init(struct mutex *lock, const char *name,
+ struct lock_class_key *key);
+extern int mutex_trylock(struct mutex *lock);
+
+static inline void mutex_destroy(struct mutex *lock) { }
+
+#define mutex_is_locked(l) rt_mutex_base_is_locked(&(l)->rtmutex)
+
+#define __mutex_init(mutex, name, key) \
+do { \
+ rt_mutex_base_init(&(mutex)->rtmutex); \
+ __mutex_rt_init((mutex), name, key); \
+} while (0)
+
+#define mutex_init(mutex) \
+do { \
+ static struct lock_class_key __key; \
+ \
+ __mutex_init((mutex), #mutex, &__key); \
+} while (0)
+#endif /* CONFIG_PREEMPT_RT */
+
/*
* See kernel/locking/mutex.c for detailed documentation of these APIs.
* Also see Documentation/locking/mutex-design.rst.
diff --git a/include/linux/preempt.h b/include/linux/preempt.h
index 9881eac0698f..4d244e295e85 100644
--- a/include/linux/preempt.h
+++ b/include/linux/preempt.h
@@ -121,7 +121,11 @@
/*
* The preempt_count offset after spin_lock()
*/
+#if !defined(CONFIG_PREEMPT_RT)
#define PREEMPT_LOCK_OFFSET PREEMPT_DISABLE_OFFSET
+#else
+#define PREEMPT_LOCK_OFFSET 0
+#endif
/*
* The preempt_count offset needed for things like:
diff --git a/include/linux/rbtree.h b/include/linux/rbtree.h
index d31ecaf4fdd3..235047d7a1b5 100644
--- a/include/linux/rbtree.h
+++ b/include/linux/rbtree.h
@@ -17,24 +17,14 @@
#ifndef _LINUX_RBTREE_H
#define _LINUX_RBTREE_H
+#include <linux/rbtree_types.h>
+
#include <linux/kernel.h>
#include <linux/stddef.h>
#include <linux/rcupdate.h>
-struct rb_node {
- unsigned long __rb_parent_color;
- struct rb_node *rb_right;
- struct rb_node *rb_left;
-} __attribute__((aligned(sizeof(long))));
- /* The alignment might seem pointless, but allegedly CRIS needs it */
-
-struct rb_root {
- struct rb_node *rb_node;
-};
-
#define rb_parent(r) ((struct rb_node *)((r)->__rb_parent_color & ~3))
-#define RB_ROOT (struct rb_root) { NULL, }
#define rb_entry(ptr, type, member) container_of(ptr, type, member)
#define RB_EMPTY_ROOT(root) (READ_ONCE((root)->rb_node) == NULL)
@@ -112,23 +102,6 @@ static inline void rb_link_node_rcu(struct rb_node *node, struct rb_node *parent
typeof(*pos), field); 1; }); \
pos = n)
-/*
- * Leftmost-cached rbtrees.
- *
- * We do not cache the rightmost node based on footprint
- * size vs number of potential users that could benefit
- * from O(1) rb_last(). Just not worth it, users that want
- * this feature can always implement the logic explicitly.
- * Furthermore, users that want to cache both pointers may
- * find it a bit asymmetric, but that's ok.
- */
-struct rb_root_cached {
- struct rb_root rb_root;
- struct rb_node *rb_leftmost;
-};
-
-#define RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL }
-
/* Same as rb_first(), but O(1) */
#define rb_first_cached(root) (root)->rb_leftmost
diff --git a/include/linux/rbtree_types.h b/include/linux/rbtree_types.h
new file mode 100644
index 000000000000..45b6ecde3665
--- /dev/null
+++ b/include/linux/rbtree_types.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _LINUX_RBTREE_TYPES_H
+#define _LINUX_RBTREE_TYPES_H
+
+struct rb_node {
+ unsigned long __rb_parent_color;
+ struct rb_node *rb_right;
+ struct rb_node *rb_left;
+} __attribute__((aligned(sizeof(long))));
+/* The alignment might seem pointless, but allegedly CRIS needs it */
+
+struct rb_root {
+ struct rb_node *rb_node;
+};
+
+/*
+ * Leftmost-cached rbtrees.
+ *
+ * We do not cache the rightmost node based on footprint
+ * size vs number of potential users that could benefit
+ * from O(1) rb_last(). Just not worth it, users that want
+ * this feature can always implement the logic explicitly.
+ * Furthermore, users that want to cache both pointers may
+ * find it a bit asymmetric, but that's ok.
+ */
+struct rb_root_cached {
+ struct rb_root rb_root;
+ struct rb_node *rb_leftmost;
+};
+
+#define RB_ROOT (struct rb_root) { NULL, }
+#define RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL }
+
+#endif
diff --git a/include/linux/rtmutex.h b/include/linux/rtmutex.h
index d1672de9ca89..9deedfeec2b1 100644
--- a/include/linux/rtmutex.h
+++ b/include/linux/rtmutex.h
@@ -13,12 +13,39 @@
#ifndef __LINUX_RT_MUTEX_H
#define __LINUX_RT_MUTEX_H
+#include <linux/compiler.h>
#include <linux/linkage.h>
-#include <linux/rbtree.h>
-#include <linux/spinlock_types.h>
+#include <linux/rbtree_types.h>
+#include <linux/spinlock_types_raw.h>
extern int max_lock_depth; /* for sysctl */
+struct rt_mutex_base {
+ raw_spinlock_t wait_lock;
+ struct rb_root_cached waiters;
+ struct task_struct *owner;
+};
+
+#define __RT_MUTEX_BASE_INITIALIZER(rtbasename) \
+{ \
+ .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(rtbasename.wait_lock), \
+ .waiters = RB_ROOT_CACHED, \
+ .owner = NULL \
+}
+
+/**
+ * rt_mutex_base_is_locked - is the rtmutex locked
+ * @lock: the mutex to be queried
+ *
+ * Returns true if the mutex is locked, false if unlocked.
+ */
+static inline bool rt_mutex_base_is_locked(struct rt_mutex_base *lock)
+{
+ return READ_ONCE(lock->owner) != NULL;
+}
+
+extern void rt_mutex_base_init(struct rt_mutex_base *rtb);
+
/**
* The rt_mutex structure
*
@@ -28,9 +55,7 @@ extern int max_lock_depth; /* for sysctl */
* @owner: the mutex owner
*/
struct rt_mutex {
- raw_spinlock_t wait_lock;
- struct rb_root_cached waiters;
- struct task_struct *owner;
+ struct rt_mutex_base rtmutex;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
struct lockdep_map dep_map;
#endif
@@ -52,32 +77,24 @@ do { \
} while (0)
#ifdef CONFIG_DEBUG_LOCK_ALLOC
-#define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname) \
- , .dep_map = { .name = #mutexname }
+#define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname) \
+ .dep_map = { \
+ .name = #mutexname, \
+ .wait_type_inner = LD_WAIT_SLEEP, \
+ }
#else
#define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)
#endif
-#define __RT_MUTEX_INITIALIZER(mutexname) \
- { .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \
- , .waiters = RB_ROOT_CACHED \
- , .owner = NULL \
- __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)}
+#define __RT_MUTEX_INITIALIZER(mutexname) \
+{ \
+ .rtmutex = __RT_MUTEX_BASE_INITIALIZER(mutexname.rtmutex), \
+ __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname) \
+}
#define DEFINE_RT_MUTEX(mutexname) \
struct rt_mutex mutexname = __RT_MUTEX_INITIALIZER(mutexname)
-/**
- * rt_mutex_is_locked - is the mutex locked
- * @lock: the mutex to be queried
- *
- * Returns 1 if the mutex is locked, 0 if unlocked.
- */
-static inline int rt_mutex_is_locked(struct rt_mutex *lock)
-{
- return lock->owner != NULL;
-}
-
extern void __rt_mutex_init(struct rt_mutex *lock, const char *name, struct lock_class_key *key);
#ifdef CONFIG_DEBUG_LOCK_ALLOC
diff --git a/include/linux/rwbase_rt.h b/include/linux/rwbase_rt.h
new file mode 100644
index 000000000000..1d264dd08625
--- /dev/null
+++ b/include/linux/rwbase_rt.h
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef _LINUX_RWBASE_RT_H
+#define _LINUX_RWBASE_RT_H
+
+#include <linux/rtmutex.h>
+#include <linux/atomic.h>
+
+#define READER_BIAS (1U << 31)
+#define WRITER_BIAS (1U << 30)
+
+struct rwbase_rt {
+ atomic_t readers;
+ struct rt_mutex_base rtmutex;
+};
+
+#define __RWBASE_INITIALIZER(name) \
+{ \
+ .readers = ATOMIC_INIT(READER_BIAS), \
+ .rtmutex = __RT_MUTEX_BASE_INITIALIZER(name.rtmutex), \
+}
+
+#define init_rwbase_rt(rwbase) \
+ do { \
+ rt_mutex_base_init(&(rwbase)->rtmutex); \
+ atomic_set(&(rwbase)->readers, READER_BIAS); \
+ } while (0)
+
+
+static __always_inline bool rw_base_is_locked(struct rwbase_rt *rwb)
+{
+ return atomic_read(&rwb->readers) != READER_BIAS;
+}
+
+static __always_inline bool rw_base_is_contended(struct rwbase_rt *rwb)
+{
+ return atomic_read(&rwb->readers) > 0;
+}
+
+#endif /* _LINUX_RWBASE_RT_H */
diff --git a/include/linux/rwlock_rt.h b/include/linux/rwlock_rt.h
new file mode 100644
index 000000000000..49c1f3842ed5
--- /dev/null
+++ b/include/linux/rwlock_rt.h
@@ -0,0 +1,140 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef __LINUX_RWLOCK_RT_H
+#define __LINUX_RWLOCK_RT_H
+
+#ifndef __LINUX_SPINLOCK_RT_H
+#error Do not #include directly. Use <linux/spinlock.h>.
+#endif
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+extern void __rt_rwlock_init(rwlock_t *rwlock, const char *name,
+ struct lock_class_key *key);
+#else
+static inline void __rt_rwlock_init(rwlock_t *rwlock, char *name,
+ struct lock_class_key *key)
+{
+}
+#endif
+
+#define rwlock_init(rwl) \
+do { \
+ static struct lock_class_key __key; \
+ \
+ init_rwbase_rt(&(rwl)->rwbase); \
+ __rt_rwlock_init(rwl, #rwl, &__key); \
+} while (0)
+
+extern void rt_read_lock(rwlock_t *rwlock);
+extern int rt_read_trylock(rwlock_t *rwlock);
+extern void rt_read_unlock(rwlock_t *rwlock);
+extern void rt_write_lock(rwlock_t *rwlock);
+extern int rt_write_trylock(rwlock_t *rwlock);
+extern void rt_write_unlock(rwlock_t *rwlock);
+
+static __always_inline void read_lock(rwlock_t *rwlock)
+{
+ rt_read_lock(rwlock);
+}
+
+static __always_inline void read_lock_bh(rwlock_t *rwlock)
+{
+ local_bh_disable();
+ rt_read_lock(rwlock);
+}
+
+static __always_inline void read_lock_irq(rwlock_t *rwlock)
+{
+ rt_read_lock(rwlock);
+}
+
+#define read_lock_irqsave(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ rt_read_lock(lock); \
+ flags = 0; \
+ } while (0)
+
+#define read_trylock(lock) __cond_lock(lock, rt_read_trylock(lock))
+
+static __always_inline void read_unlock(rwlock_t *rwlock)
+{
+ rt_read_unlock(rwlock);
+}
+
+static __always_inline void read_unlock_bh(rwlock_t *rwlock)
+{
+ rt_read_unlock(rwlock);
+ local_bh_enable();
+}
+
+static __always_inline void read_unlock_irq(rwlock_t *rwlock)
+{
+ rt_read_unlock(rwlock);
+}
+
+static __always_inline void read_unlock_irqrestore(rwlock_t *rwlock,
+ unsigned long flags)
+{
+ rt_read_unlock(rwlock);
+}
+
+static __always_inline void write_lock(rwlock_t *rwlock)
+{
+ rt_write_lock(rwlock);
+}
+
+static __always_inline void write_lock_bh(rwlock_t *rwlock)
+{
+ local_bh_disable();
+ rt_write_lock(rwlock);
+}
+
+static __always_inline void write_lock_irq(rwlock_t *rwlock)
+{
+ rt_write_lock(rwlock);
+}
+
+#define write_lock_irqsave(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ rt_write_lock(lock); \
+ flags = 0; \
+ } while (0)
+
+#define write_trylock(lock) __cond_lock(lock, rt_write_trylock(lock))
+
+#define write_trylock_irqsave(lock, flags) \
+({ \
+ int __locked; \
+ \
+ typecheck(unsigned long, flags); \
+ flags = 0; \
+ __locked = write_trylock(lock); \
+ __locked; \
+})
+
+static __always_inline void write_unlock(rwlock_t *rwlock)
+{
+ rt_write_unlock(rwlock);
+}
+
+static __always_inline void write_unlock_bh(rwlock_t *rwlock)
+{
+ rt_write_unlock(rwlock);
+ local_bh_enable();
+}
+
+static __always_inline void write_unlock_irq(rwlock_t *rwlock)
+{
+ rt_write_unlock(rwlock);
+}
+
+static __always_inline void write_unlock_irqrestore(rwlock_t *rwlock,
+ unsigned long flags)
+{
+ rt_write_unlock(rwlock);
+}
+
+#define rwlock_is_contended(lock) (((void)(lock), 0))
+
+#endif /* __LINUX_RWLOCK_RT_H */
diff --git a/include/linux/rwlock_types.h b/include/linux/rwlock_types.h
index 3bd03e18061c..1948442e7750 100644
--- a/include/linux/rwlock_types.h
+++ b/include/linux/rwlock_types.h
@@ -1,9 +1,23 @@
#ifndef __LINUX_RWLOCK_TYPES_H
#define __LINUX_RWLOCK_TYPES_H
+#if !defined(__LINUX_SPINLOCK_TYPES_H)
+# error "Do not include directly, include spinlock_types.h"
+#endif
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define RW_DEP_MAP_INIT(lockname) \
+ .dep_map = { \
+ .name = #lockname, \
+ .wait_type_inner = LD_WAIT_CONFIG, \
+ }
+#else
+# define RW_DEP_MAP_INIT(lockname)
+#endif
+
+#ifndef CONFIG_PREEMPT_RT
/*
- * include/linux/rwlock_types.h - generic rwlock type definitions
- * and initializers
+ * generic rwlock type definitions and initializers
*
* portions Copyright 2005, Red Hat, Inc., Ingo Molnar
* Released under the General Public License (GPL).
@@ -21,16 +35,6 @@ typedef struct {
#define RWLOCK_MAGIC 0xdeaf1eed
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define RW_DEP_MAP_INIT(lockname) \
- .dep_map = { \
- .name = #lockname, \
- .wait_type_inner = LD_WAIT_CONFIG, \
- }
-#else
-# define RW_DEP_MAP_INIT(lockname)
-#endif
-
#ifdef CONFIG_DEBUG_SPINLOCK
#define __RW_LOCK_UNLOCKED(lockname) \
(rwlock_t) { .raw_lock = __ARCH_RW_LOCK_UNLOCKED, \
@@ -46,4 +50,29 @@ typedef struct {
#define DEFINE_RWLOCK(x) rwlock_t x = __RW_LOCK_UNLOCKED(x)
+#else /* !CONFIG_PREEMPT_RT */
+
+#include <linux/rwbase_rt.h>
+
+typedef struct {
+ struct rwbase_rt rwbase;
+ atomic_t readers;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
+} rwlock_t;
+
+#define __RWLOCK_RT_INITIALIZER(name) \
+{ \
+ .rwbase = __RWBASE_INITIALIZER(name), \
+ RW_DEP_MAP_INIT(name) \
+}
+
+#define __RW_LOCK_UNLOCKED(name) __RWLOCK_RT_INITIALIZER(name)
+
+#define DEFINE_RWLOCK(name) \
+ rwlock_t name = __RW_LOCK_UNLOCKED(name)
+
+#endif /* CONFIG_PREEMPT_RT */
+
#endif /* __LINUX_RWLOCK_TYPES_H */
diff --git a/include/linux/rwsem.h b/include/linux/rwsem.h
index a66038d88878..426e98e0b675 100644
--- a/include/linux/rwsem.h
+++ b/include/linux/rwsem.h
@@ -16,6 +16,19 @@
#include <linux/spinlock.h>
#include <linux/atomic.h>
#include <linux/err.h>
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define __RWSEM_DEP_MAP_INIT(lockname) \
+ .dep_map = { \
+ .name = #lockname, \
+ .wait_type_inner = LD_WAIT_SLEEP, \
+ },
+#else
+# define __RWSEM_DEP_MAP_INIT(lockname)
+#endif
+
+#ifndef CONFIG_PREEMPT_RT
+
#ifdef CONFIG_RWSEM_SPIN_ON_OWNER
#include <linux/osq_lock.h>
#endif
@@ -64,16 +77,6 @@ static inline int rwsem_is_locked(struct rw_semaphore *sem)
/* Common initializer macros and functions */
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define __RWSEM_DEP_MAP_INIT(lockname) \
- .dep_map = { \
- .name = #lockname, \
- .wait_type_inner = LD_WAIT_SLEEP, \
- },
-#else
-# define __RWSEM_DEP_MAP_INIT(lockname)
-#endif
-
#ifdef CONFIG_DEBUG_RWSEMS
# define __RWSEM_DEBUG_INIT(lockname) .magic = &lockname,
#else
@@ -119,6 +122,61 @@ static inline int rwsem_is_contended(struct rw_semaphore *sem)
return !list_empty(&sem->wait_list);
}
+#else /* !CONFIG_PREEMPT_RT */
+
+#include <linux/rwbase_rt.h>
+
+struct rw_semaphore {
+ struct rwbase_rt rwbase;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
+};
+
+#define __RWSEM_INITIALIZER(name) \
+ { \
+ .rwbase = __RWBASE_INITIALIZER(name), \
+ __RWSEM_DEP_MAP_INIT(name) \
+ }
+
+#define DECLARE_RWSEM(lockname) \
+ struct rw_semaphore lockname = __RWSEM_INITIALIZER(lockname)
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+extern void __rwsem_init(struct rw_semaphore *rwsem, const char *name,
+ struct lock_class_key *key);
+#else
+static inline void __rwsem_init(struct rw_semaphore *rwsem, const char *name,
+ struct lock_class_key *key)
+{
+}
+#endif
+
+#define init_rwsem(sem) \
+do { \
+ static struct lock_class_key __key; \
+ \
+ init_rwbase_rt(&(sem)->rwbase); \
+ __rwsem_init((sem), #sem, &__key); \
+} while (0)
+
+static __always_inline int rwsem_is_locked(struct rw_semaphore *sem)
+{
+ return rw_base_is_locked(&sem->rwbase);
+}
+
+static __always_inline int rwsem_is_contended(struct rw_semaphore *sem)
+{
+ return rw_base_is_contended(&sem->rwbase);
+}
+
+#endif /* CONFIG_PREEMPT_RT */
+
+/*
+ * The functions below are the same for all rwsem implementations including
+ * the RT specific variant.
+ */
+
/*
* lock for reading
*/
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 7c6a77da8b10..af7179f8572c 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -95,7 +95,9 @@ struct task_group;
#define TASK_WAKING 0x0200
#define TASK_NOLOAD 0x0400
#define TASK_NEW 0x0800
-#define TASK_STATE_MAX 0x1000
+/* RT specific auxilliary flag to mark RT lock waiters */
+#define TASK_RTLOCK_WAIT 0x1000
+#define TASK_STATE_MAX 0x2000
/* Convenience macros for the sake of set_current_state: */
#define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
@@ -121,8 +123,6 @@ struct task_group;
#define task_is_stopped_or_traced(task) ((READ_ONCE(task->__state) & (__TASK_STOPPED | __TASK_TRACED)) != 0)
-#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
-
/*
* Special states are those that do not use the normal wait-loop pattern. See
* the comment with set_special_state().
@@ -130,30 +130,37 @@ struct task_group;
#define is_special_task_state(state) \
((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD))
-#define __set_current_state(state_value) \
- do { \
- WARN_ON_ONCE(is_special_task_state(state_value));\
- current->task_state_change = _THIS_IP_; \
- WRITE_ONCE(current->__state, (state_value)); \
- } while (0)
-
-#define set_current_state(state_value) \
- do { \
- WARN_ON_ONCE(is_special_task_state(state_value));\
- current->task_state_change = _THIS_IP_; \
- smp_store_mb(current->__state, (state_value)); \
+#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
+# define debug_normal_state_change(state_value) \
+ do { \
+ WARN_ON_ONCE(is_special_task_state(state_value)); \
+ current->task_state_change = _THIS_IP_; \
} while (0)
-#define set_special_state(state_value) \
+# define debug_special_state_change(state_value) \
do { \
- unsigned long flags; /* may shadow */ \
WARN_ON_ONCE(!is_special_task_state(state_value)); \
- raw_spin_lock_irqsave(&current->pi_lock, flags); \
current->task_state_change = _THIS_IP_; \
- WRITE_ONCE(current->__state, (state_value)); \
- raw_spin_unlock_irqrestore(&current->pi_lock, flags); \
} while (0)
+
+# define debug_rtlock_wait_set_state() \
+ do { \
+ current->saved_state_change = current->task_state_change;\
+ current->task_state_change = _THIS_IP_; \
+ } while (0)
+
+# define debug_rtlock_wait_restore_state() \
+ do { \
+ current->task_state_change = current->saved_state_change;\
+ } while (0)
+
#else
+# define debug_normal_state_change(cond) do { } while (0)
+# define debug_special_state_change(cond) do { } while (0)
+# define debug_rtlock_wait_set_state() do { } while (0)
+# define debug_rtlock_wait_restore_state() do { } while (0)
+#endif
+
/*
* set_current_state() includes a barrier so that the write of current->state
* is correctly serialised wrt the caller's subsequent test of whether to
@@ -192,26 +199,77 @@ struct task_group;
* Also see the comments of try_to_wake_up().
*/
#define __set_current_state(state_value) \
- WRITE_ONCE(current->__state, (state_value))
+ do { \
+ debug_normal_state_change((state_value)); \
+ WRITE_ONCE(current->__state, (state_value)); \
+ } while (0)
#define set_current_state(state_value) \
- smp_store_mb(current->__state, (state_value))
+ do { \
+ debug_normal_state_change((state_value)); \
+ smp_store_mb(current->__state, (state_value)); \
+ } while (0)
/*
* set_special_state() should be used for those states when the blocking task
* can not use the regular condition based wait-loop. In that case we must
- * serialize against wakeups such that any possible in-flight TASK_RUNNING stores
- * will not collide with our state change.
+ * serialize against wakeups such that any possible in-flight TASK_RUNNING
+ * stores will not collide with our state change.
*/
#define set_special_state(state_value) \
do { \
unsigned long flags; /* may shadow */ \
+ \
raw_spin_lock_irqsave(&current->pi_lock, flags); \
+ debug_special_state_change((state_value)); \
WRITE_ONCE(current->__state, (state_value)); \
raw_spin_unlock_irqrestore(&current->pi_lock, flags); \
} while (0)
-#endif
+/*
+ * PREEMPT_RT specific variants for "sleeping" spin/rwlocks
+ *
+ * RT's spin/rwlock substitutions are state preserving. The state of the
+ * task when blocking on the lock is saved in task_struct::saved_state and
+ * restored after the lock has been acquired. These operations are
+ * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT
+ * lock related wakeups while the task is blocked on the lock are
+ * redirected to operate on task_struct::saved_state to ensure that these
+ * are not dropped. On restore task_struct::saved_state is set to
+ * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail.
+ *
+ * The lock operation looks like this:
+ *
+ * current_save_and_set_rtlock_wait_state();
+ * for (;;) {
+ * if (try_lock())
+ * break;
+ * raw_spin_unlock_irq(&lock->wait_lock);
+ * schedule_rtlock();
+ * raw_spin_lock_irq(&lock->wait_lock);
+ * set_current_state(TASK_RTLOCK_WAIT);
+ * }
+ * current_restore_rtlock_saved_state();
+ */
+#define current_save_and_set_rtlock_wait_state() \
+ do { \
+ lockdep_assert_irqs_disabled(); \
+ raw_spin_lock(&current->pi_lock); \
+ current->saved_state = current->__state; \
+ debug_rtlock_wait_set_state(); \
+ WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT); \
+ raw_spin_unlock(&current->pi_lock); \
+ } while (0);
+
+#define current_restore_rtlock_saved_state() \
+ do { \
+ lockdep_assert_irqs_disabled(); \
+ raw_spin_lock(&current->pi_lock); \
+ debug_rtlock_wait_restore_state(); \
+ WRITE_ONCE(current->__state, current->saved_state); \
+ current->saved_state = TASK_RUNNING; \
+ raw_spin_unlock(&current->pi_lock); \
+ } while (0);
#define get_current_state() READ_ONCE(current->__state)
@@ -230,6 +288,9 @@ extern long schedule_timeout_idle(long timeout);
asmlinkage void schedule(void);
extern void schedule_preempt_disabled(void);
asmlinkage void preempt_schedule_irq(void);
+#ifdef CONFIG_PREEMPT_RT
+ extern void schedule_rtlock(void);
+#endif
extern int __must_check io_schedule_prepare(void);
extern void io_schedule_finish(int token);
@@ -668,6 +729,11 @@ struct task_struct {
#endif
unsigned int __state;
+#ifdef CONFIG_PREEMPT_RT
+ /* saved state for "spinlock sleepers" */
+ unsigned int saved_state;
+#endif
+
/*
* This begins the randomizable portion of task_struct. Only
* scheduling-critical items should be added above here.
@@ -1362,6 +1428,9 @@ struct task_struct {
struct kmap_ctrl kmap_ctrl;
#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
unsigned long task_state_change;
+# ifdef CONFIG_PREEMPT_RT
+ unsigned long saved_state_change;
+# endif
#endif
int pagefault_disabled;
#ifdef CONFIG_MMU
diff --git a/include/linux/sched/wake_q.h b/include/linux/sched/wake_q.h
index 26a2013ac39c..06cd8fb2f409 100644
--- a/include/linux/sched/wake_q.h
+++ b/include/linux/sched/wake_q.h
@@ -42,8 +42,11 @@ struct wake_q_head {
#define WAKE_Q_TAIL ((struct wake_q_node *) 0x01)
-#define DEFINE_WAKE_Q(name) \
- struct wake_q_head name = { WAKE_Q_TAIL, &name.first }
+#define WAKE_Q_HEAD_INITIALIZER(name) \
+ { WAKE_Q_TAIL, &name.first }
+
+#define DEFINE_WAKE_Q(name) \
+ struct wake_q_head name = WAKE_Q_HEAD_INITIALIZER(name)
static inline void wake_q_init(struct wake_q_head *head)
{
diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
index 79897841a2cc..45310ea1b1d7 100644
--- a/include/linux/spinlock.h
+++ b/include/linux/spinlock.h
@@ -12,6 +12,8 @@
* asm/spinlock_types.h: contains the arch_spinlock_t/arch_rwlock_t and the
* initializers
*
+ * linux/spinlock_types_raw:
+ * The raw types and initializers
* linux/spinlock_types.h:
* defines the generic type and initializers
*
@@ -31,6 +33,8 @@
* contains the generic, simplified UP spinlock type.
* (which is an empty structure on non-debug builds)
*
+ * linux/spinlock_types_raw:
+ * The raw RT types and initializers
* linux/spinlock_types.h:
* defines the generic type and initializers
*
@@ -308,8 +312,10 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
1 : ({ local_irq_restore(flags); 0; }); \
})
-/* Include rwlock functions */
+#ifndef CONFIG_PREEMPT_RT
+/* Include rwlock functions for !RT */
#include <linux/rwlock.h>
+#endif
/*
* Pull the _spin_*()/_read_*()/_write_*() functions/declarations:
@@ -320,6 +326,9 @@ static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
# include <linux/spinlock_api_up.h>
#endif
+/* Non PREEMPT_RT kernel, map to raw spinlocks: */
+#ifndef CONFIG_PREEMPT_RT
+
/*
* Map the spin_lock functions to the raw variants for PREEMPT_RT=n
*/
@@ -454,6 +463,10 @@ static __always_inline int spin_is_contended(spinlock_t *lock)
#define assert_spin_locked(lock) assert_raw_spin_locked(&(lock)->rlock)
+#else /* !CONFIG_PREEMPT_RT */
+# include <linux/spinlock_rt.h>
+#endif /* CONFIG_PREEMPT_RT */
+
/*
* Pull the atomic_t declaration:
* (asm-mips/atomic.h needs above definitions)
diff --git a/include/linux/spinlock_api_smp.h b/include/linux/spinlock_api_smp.h
index 19a9be9d97ee..6b8e1a0b137b 100644
--- a/include/linux/spinlock_api_smp.h
+++ b/include/linux/spinlock_api_smp.h
@@ -187,6 +187,9 @@ static inline int __raw_spin_trylock_bh(raw_spinlock_t *lock)
return 0;
}
+/* PREEMPT_RT has its own rwlock implementation */
+#ifndef CONFIG_PREEMPT_RT
#include <linux/rwlock_api_smp.h>
+#endif
#endif /* __LINUX_SPINLOCK_API_SMP_H */
diff --git a/include/linux/spinlock_rt.h b/include/linux/spinlock_rt.h
new file mode 100644
index 000000000000..835aedaf68ac
--- /dev/null
+++ b/include/linux/spinlock_rt.h
@@ -0,0 +1,159 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef __LINUX_SPINLOCK_RT_H
+#define __LINUX_SPINLOCK_RT_H
+
+#ifndef __LINUX_SPINLOCK_H
+#error Do not include directly. Use spinlock.h
+#endif
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+extern void __rt_spin_lock_init(spinlock_t *lock, const char *name,
+ struct lock_class_key *key, bool percpu);
+#else
+static inline void __rt_spin_lock_init(spinlock_t *lock, const char *name,
+ struct lock_class_key *key, bool percpu)
+{
+}
+#endif
+
+#define spin_lock_init(slock) \
+do { \
+ static struct lock_class_key __key; \
+ \
+ rt_mutex_base_init(&(slock)->lock); \
+ __rt_spin_lock_init(slock, #slock, &__key, false); \
+} while (0)
+
+#define local_spin_lock_init(slock) \
+do { \
+ static struct lock_class_key __key; \
+ \
+ rt_mutex_base_init(&(slock)->lock); \
+ __rt_spin_lock_init(slock, #slock, &__key, true); \
+} while (0)
+
+extern void rt_spin_lock(spinlock_t *lock);
+extern void rt_spin_lock_nested(spinlock_t *lock, int subclass);
+extern void rt_spin_lock_nest_lock(spinlock_t *lock, struct lockdep_map *nest_lock);
+extern void rt_spin_unlock(spinlock_t *lock);
+extern void rt_spin_lock_unlock(spinlock_t *lock);
+extern int rt_spin_trylock_bh(spinlock_t *lock);
+extern int rt_spin_trylock(spinlock_t *lock);
+
+static __always_inline void spin_lock(spinlock_t *lock)
+{
+ rt_spin_lock(lock);
+}
+
+#ifdef CONFIG_LOCKDEP
+# define __spin_lock_nested(lock, subclass) \
+ rt_spin_lock_nested(lock, subclass)
+
+# define __spin_lock_nest_lock(lock, nest_lock) \
+ do { \
+ typecheck(struct lockdep_map *, &(nest_lock)->dep_map); \
+ rt_spin_lock_nest_lock(lock, &(nest_lock)->dep_map); \
+ } while (0)
+# define __spin_lock_irqsave_nested(lock, flags, subclass) \
+ do { \
+ typecheck(unsigned long, flags); \
+ flags = 0; \
+ __spin_lock_nested(lock, subclass); \
+ } while (0)
+
+#else
+ /*
+ * Always evaluate the 'subclass' argument to avoid that the compiler
+ * warns about set-but-not-used variables when building with
+ * CONFIG_DEBUG_LOCK_ALLOC=n and with W=1.
+ */
+# define __spin_lock_nested(lock, subclass) spin_lock(((void)(subclass), (lock)))
+# define __spin_lock_nest_lock(lock, subclass) spin_lock(((void)(subclass), (lock)))
+# define __spin_lock_irqsave_nested(lock, flags, subclass) \
+ spin_lock_irqsave(((void)(subclass), (lock)), flags)
+#endif
+
+#define spin_lock_nested(lock, subclass) \
+ __spin_lock_nested(lock, subclass)
+
+#define spin_lock_nest_lock(lock, nest_lock) \
+ __spin_lock_nest_lock(lock, nest_lock)
+
+#define spin_lock_irqsave_nested(lock, flags, subclass) \
+ __spin_lock_irqsave_nested(lock, flags, subclass)
+
+static __always_inline void spin_lock_bh(spinlock_t *lock)
+{
+ /* Investigate: Drop bh when blocking ? */
+ local_bh_disable();
+ rt_spin_lock(lock);
+}
+
+static __always_inline void spin_lock_irq(spinlock_t *lock)
+{
+ rt_spin_lock(lock);
+}
+
+#define spin_lock_irqsave(lock, flags) \
+ do { \
+ typecheck(unsigned long, flags); \
+ flags = 0; \
+ spin_lock(lock); \
+ } while (0)
+
+static __always_inline void spin_unlock(spinlock_t *lock)
+{
+ rt_spin_unlock(lock);
+}
+
+static __always_inline void spin_unlock_bh(spinlock_t *lock)
+{
+ rt_spin_unlock(lock);
+ local_bh_enable();
+}
+
+static __always_inline void spin_unlock_irq(spinlock_t *lock)
+{
+ rt_spin_unlock(lock);
+}
+
+static __always_inline void spin_unlock_irqrestore(spinlock_t *lock,
+ unsigned long flags)
+{
+ rt_spin_unlock(lock);
+}
+
+#define spin_trylock(lock) \
+ __cond_lock(lock, rt_spin_trylock(lock))
+
+#define spin_trylock_bh(lock) \
+ __cond_lock(lock, rt_spin_trylock_bh(lock))
+
+#define spin_trylock_irq(lock) \
+ __cond_lock(lock, rt_spin_trylock(lock))
+
+#define __spin_trylock_irqsave(lock, flags) \
+({ \
+ int __locked; \
+ \
+ typecheck(unsigned long, flags); \
+ flags = 0; \
+ __locked = spin_trylock(lock); \
+ __locked; \
+})
+
+#define spin_trylock_irqsave(lock, flags) \
+ __cond_lock(lock, __spin_trylock_irqsave(lock, flags))
+
+#define spin_is_contended(lock) (((void)(lock), 0))
+
+static inline int spin_is_locked(spinlock_t *lock)
+{
+ return rt_mutex_base_is_locked(&lock->lock);
+}
+
+#define assert_spin_locked(lock) BUG_ON(!spin_is_locked(lock))
+
+#include <linux/rwlock_rt.h>
+
+#endif
diff --git a/include/linux/spinlock_types.h b/include/linux/spinlock_types.h
index b981caafe8bf..2dfa35ffec76 100644
--- a/include/linux/spinlock_types.h
+++ b/include/linux/spinlock_types.h
@@ -9,65 +9,11 @@
* Released under the General Public License (GPL).
*/
-#if defined(CONFIG_SMP)
-# include <asm/spinlock_types.h>
-#else
-# include <linux/spinlock_types_up.h>
-#endif
-
-#include <linux/lockdep_types.h>
+#include <linux/spinlock_types_raw.h>
-typedef struct raw_spinlock {
- arch_spinlock_t raw_lock;
-#ifdef CONFIG_DEBUG_SPINLOCK
- unsigned int magic, owner_cpu;
- void *owner;
-#endif
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
- struct lockdep_map dep_map;
-#endif
-} raw_spinlock_t;
-
-#define SPINLOCK_MAGIC 0xdead4ead
-
-#define SPINLOCK_OWNER_INIT ((void *)-1L)
-
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-# define RAW_SPIN_DEP_MAP_INIT(lockname) \
- .dep_map = { \
- .name = #lockname, \
- .wait_type_inner = LD_WAIT_SPIN, \
- }
-# define SPIN_DEP_MAP_INIT(lockname) \
- .dep_map = { \
- .name = #lockname, \
- .wait_type_inner = LD_WAIT_CONFIG, \
- }
-#else
-# define RAW_SPIN_DEP_MAP_INIT(lockname)
-# define SPIN_DEP_MAP_INIT(lockname)
-#endif
-
-#ifdef CONFIG_DEBUG_SPINLOCK
-# define SPIN_DEBUG_INIT(lockname) \
- .magic = SPINLOCK_MAGIC, \
- .owner_cpu = -1, \
- .owner = SPINLOCK_OWNER_INIT,
-#else
-# define SPIN_DEBUG_INIT(lockname)
-#endif
-
-#define __RAW_SPIN_LOCK_INITIALIZER(lockname) \
- { \
- .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED, \
- SPIN_DEBUG_INIT(lockname) \
- RAW_SPIN_DEP_MAP_INIT(lockname) }
-
-#define __RAW_SPIN_LOCK_UNLOCKED(lockname) \
- (raw_spinlock_t) __RAW_SPIN_LOCK_INITIALIZER(lockname)
-
-#define DEFINE_RAW_SPINLOCK(x) raw_spinlock_t x = __RAW_SPIN_LOCK_UNLOCKED(x)
+#ifndef CONFIG_PREEMPT_RT
+/* Non PREEMPT_RT kernels map spinlock to raw_spinlock */
typedef struct spinlock {
union {
struct raw_spinlock rlock;
@@ -96,6 +42,35 @@ typedef struct spinlock {
#define DEFINE_SPINLOCK(x) spinlock_t x = __SPIN_LOCK_UNLOCKED(x)
+#else /* !CONFIG_PREEMPT_RT */
+
+/* PREEMPT_RT kernels map spinlock to rt_mutex */
+#include <linux/rtmutex.h>
+
+typedef struct spinlock {
+ struct rt_mutex_base lock;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
+} spinlock_t;
+
+#define __SPIN_LOCK_UNLOCKED(name) \
+ { \
+ .lock = __RT_MUTEX_BASE_INITIALIZER(name.lock), \
+ SPIN_DEP_MAP_INIT(name) \
+ }
+
+#define __LOCAL_SPIN_LOCK_UNLOCKED(name) \
+ { \
+ .lock = __RT_MUTEX_BASE_INITIALIZER(name.lock), \
+ LOCAL_SPIN_DEP_MAP_INIT(name) \
+ }
+
+#define DEFINE_SPINLOCK(name) \
+ spinlock_t name = __SPIN_LOCK_UNLOCKED(name)
+
+#endif /* CONFIG_PREEMPT_RT */
+
#include <linux/rwlock_types.h>
#endif /* __LINUX_SPINLOCK_TYPES_H */
diff --git a/include/linux/spinlock_types_raw.h b/include/linux/spinlock_types_raw.h
new file mode 100644
index 000000000000..91cb36b65a17
--- /dev/null
+++ b/include/linux/spinlock_types_raw.h
@@ -0,0 +1,73 @@
+#ifndef __LINUX_SPINLOCK_TYPES_RAW_H
+#define __LINUX_SPINLOCK_TYPES_RAW_H
+
+#include <linux/types.h>
+
+#if defined(CONFIG_SMP)
+# include <asm/spinlock_types.h>
+#else
+# include <linux/spinlock_types_up.h>
+#endif
+
+#include <linux/lockdep_types.h>
+
+typedef struct raw_spinlock {
+ arch_spinlock_t raw_lock;
+#ifdef CONFIG_DEBUG_SPINLOCK
+ unsigned int magic, owner_cpu;
+ void *owner;
+#endif
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
+} raw_spinlock_t;
+
+#define SPINLOCK_MAGIC 0xdead4ead
+
+#define SPINLOCK_OWNER_INIT ((void *)-1L)
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define RAW_SPIN_DEP_MAP_INIT(lockname) \
+ .dep_map = { \
+ .name = #lockname, \
+ .wait_type_inner = LD_WAIT_SPIN, \
+ }
+# define SPIN_DEP_MAP_INIT(lockname) \
+ .dep_map = { \
+ .name = #lockname, \
+ .wait_type_inner = LD_WAIT_CONFIG, \
+ }
+
+# define LOCAL_SPIN_DEP_MAP_INIT(lockname) \
+ .dep_map = { \
+ .name = #lockname, \
+ .wait_type_inner = LD_WAIT_CONFIG, \
+ .lock_type = LD_LOCK_PERCPU, \
+ }
+#else
+# define RAW_SPIN_DEP_MAP_INIT(lockname)
+# define SPIN_DEP_MAP_INIT(lockname)
+# define LOCAL_SPIN_DEP_MAP_INIT(lockname)
+#endif
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+# define SPIN_DEBUG_INIT(lockname) \
+ .magic = SPINLOCK_MAGIC, \
+ .owner_cpu = -1, \
+ .owner = SPINLOCK_OWNER_INIT,
+#else
+# define SPIN_DEBUG_INIT(lockname)
+#endif
+
+#define __RAW_SPIN_LOCK_INITIALIZER(lockname) \
+{ \
+ .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED, \
+ SPIN_DEBUG_INIT(lockname) \
+ RAW_SPIN_DEP_MAP_INIT(lockname) }
+
+#define __RAW_SPIN_LOCK_UNLOCKED(lockname) \
+ (raw_spinlock_t) __RAW_SPIN_LOCK_INITIALIZER(lockname)
+
+#define DEFINE_RAW_SPINLOCK(x) raw_spinlock_t x = __RAW_SPIN_LOCK_UNLOCKED(x)
+
+#endif /* __LINUX_SPINLOCK_TYPES_RAW_H */
diff --git a/include/linux/static_call.h b/include/linux/static_call.h
index fc94faa53b5b..3e56a9751c06 100644
--- a/include/linux/static_call.h
+++ b/include/linux/static_call.h
@@ -17,11 +17,17 @@
* DECLARE_STATIC_CALL(name, func);
* DEFINE_STATIC_CALL(name, func);
* DEFINE_STATIC_CALL_NULL(name, typename);
+ * DEFINE_STATIC_CALL_RET0(name, typename);
+ *
+ * __static_call_return0;
+ *
* static_call(name)(args...);
* static_call_cond(name)(args...);
* static_call_update(name, func);
* static_call_query(name);
*
+ * EXPORT_STATIC_CALL{,_TRAMP}{,_GPL}()
+ *
* Usage example:
*
* # Start with the following functions (with identical prototypes):
@@ -96,6 +102,33 @@
* To query which function is currently set to be called, use:
*
* func = static_call_query(name);
+ *
+ *
+ * DEFINE_STATIC_CALL_RET0 / __static_call_return0:
+ *
+ * Just like how DEFINE_STATIC_CALL_NULL() / static_call_cond() optimize the
+ * conditional void function call, DEFINE_STATIC_CALL_RET0 /
+ * __static_call_return0 optimize the do nothing return 0 function.
+ *
+ * This feature is strictly UB per the C standard (since it casts a function
+ * pointer to a different signature) and relies on the architecture ABI to
+ * make things work. In particular it relies on Caller Stack-cleanup and the
+ * whole return register being clobbered for short return values. All normal
+ * CDECL style ABIs conform.
+ *
+ * In particular the x86_64 implementation replaces the 5 byte CALL
+ * instruction at the callsite with a 5 byte clear of the RAX register,
+ * completely eliding any function call overhead.
+ *
+ * Notably argument setup is unconditional.
+ *
+ *
+ * EXPORT_STATIC_CALL() vs EXPORT_STATIC_CALL_TRAMP():
+ *
+ * The difference is that the _TRAMP variant tries to only export the
+ * trampoline with the result that a module can use static_call{,_cond}() but
+ * not static_call_update().
+ *
*/
#include <linux/types.h>
diff --git a/include/linux/ww_mutex.h b/include/linux/ww_mutex.h
index b77f39f319ad..29db736af86d 100644
--- a/include/linux/ww_mutex.h
+++ b/include/linux/ww_mutex.h
@@ -18,6 +18,24 @@
#define __LINUX_WW_MUTEX_H
#include <linux/mutex.h>
+#include <linux/rtmutex.h>
+
+#if defined(CONFIG_DEBUG_MUTEXES) || \
+ (defined(CONFIG_PREEMPT_RT) && defined(CONFIG_DEBUG_RT_MUTEXES))
+#define DEBUG_WW_MUTEXES
+#endif
+
+#ifndef CONFIG_PREEMPT_RT
+#define WW_MUTEX_BASE mutex
+#define ww_mutex_base_init(l,n,k) __mutex_init(l,n,k)
+#define ww_mutex_base_trylock(l) mutex_trylock(l)
+#define ww_mutex_base_is_locked(b) mutex_is_locked((b))
+#else
+#define WW_MUTEX_BASE rt_mutex
+#define ww_mutex_base_init(l,n,k) __rt_mutex_init(l,n,k)
+#define ww_mutex_base_trylock(l) rt_mutex_trylock(l)
+#define ww_mutex_base_is_locked(b) rt_mutex_base_is_locked(&(b)->rtmutex)
+#endif
struct ww_class {
atomic_long_t stamp;
@@ -28,16 +46,24 @@ struct ww_class {
unsigned int is_wait_die;
};
+struct ww_mutex {
+ struct WW_MUTEX_BASE base;
+ struct ww_acquire_ctx *ctx;
+#ifdef DEBUG_WW_MUTEXES
+ struct ww_class *ww_class;
+#endif
+};
+
struct ww_acquire_ctx {
struct task_struct *task;
unsigned long stamp;
unsigned int acquired;
unsigned short wounded;
unsigned short is_wait_die;
-#ifdef CONFIG_DEBUG_MUTEXES
+#ifdef DEBUG_WW_MUTEXES
unsigned int done_acquire;
struct ww_class *ww_class;
- struct ww_mutex *contending_lock;
+ void *contending_lock;
#endif
#ifdef CONFIG_DEBUG_LOCK_ALLOC
struct lockdep_map dep_map;
@@ -74,9 +100,9 @@ struct ww_acquire_ctx {
static inline void ww_mutex_init(struct ww_mutex *lock,
struct ww_class *ww_class)
{
- __mutex_init(&lock->base, ww_class->mutex_name, &ww_class->mutex_key);
+ ww_mutex_base_init(&lock->base, ww_class->mutex_name, &ww_class->mutex_key);
lock->ctx = NULL;
-#ifdef CONFIG_DEBUG_MUTEXES
+#ifdef DEBUG_WW_MUTEXES
lock->ww_class = ww_class;
#endif
}
@@ -113,7 +139,7 @@ static inline void ww_acquire_init(struct ww_acquire_ctx *ctx,
ctx->acquired = 0;
ctx->wounded = false;
ctx->is_wait_die = ww_class->is_wait_die;
-#ifdef CONFIG_DEBUG_MUTEXES
+#ifdef DEBUG_WW_MUTEXES
ctx->ww_class = ww_class;
ctx->done_acquire = 0;
ctx->contending_lock = NULL;
@@ -143,7 +169,7 @@ static inline void ww_acquire_init(struct ww_acquire_ctx *ctx,
*/
static inline void ww_acquire_done(struct ww_acquire_ctx *ctx)
{
-#ifdef CONFIG_DEBUG_MUTEXES
+#ifdef DEBUG_WW_MUTEXES
lockdep_assert_held(ctx);
DEBUG_LOCKS_WARN_ON(ctx->done_acquire);
@@ -163,7 +189,7 @@ static inline void ww_acquire_fini(struct ww_acquire_ctx *ctx)
#ifdef CONFIG_DEBUG_LOCK_ALLOC
mutex_release(&ctx->dep_map, _THIS_IP_);
#endif
-#ifdef CONFIG_DEBUG_MUTEXES
+#ifdef DEBUG_WW_MUTEXES
DEBUG_LOCKS_WARN_ON(ctx->acquired);
if (!IS_ENABLED(CONFIG_PROVE_LOCKING))
/*
@@ -269,7 +295,7 @@ static inline void
ww_mutex_lock_slow(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
{
int ret;
-#ifdef CONFIG_DEBUG_MUTEXES
+#ifdef DEBUG_WW_MUTEXES
DEBUG_LOCKS_WARN_ON(!ctx->contending_lock);
#endif
ret = ww_mutex_lock(lock, ctx);
@@ -305,7 +331,7 @@ static inline int __must_check
ww_mutex_lock_slow_interruptible(struct ww_mutex *lock,
struct ww_acquire_ctx *ctx)
{
-#ifdef CONFIG_DEBUG_MUTEXES
+#ifdef DEBUG_WW_MUTEXES
DEBUG_LOCKS_WARN_ON(!ctx->contending_lock);
#endif
return ww_mutex_lock_interruptible(lock, ctx);
@@ -322,7 +348,7 @@ extern void ww_mutex_unlock(struct ww_mutex *lock);
*/
static inline int __must_check ww_mutex_trylock(struct ww_mutex *lock)
{
- return mutex_trylock(&lock->base);
+ return ww_mutex_base_trylock(&lock->base);
}
/***
@@ -335,7 +361,9 @@ static inline int __must_check ww_mutex_trylock(struct ww_mutex *lock)
*/
static inline void ww_mutex_destroy(struct ww_mutex *lock)
{
+#ifndef CONFIG_PREEMPT_RT
mutex_destroy(&lock->base);
+#endif
}
/**
@@ -346,7 +374,7 @@ static inline void ww_mutex_destroy(struct ww_mutex *lock)
*/
static inline bool ww_mutex_is_locked(struct ww_mutex *lock)
{
- return mutex_is_locked(&lock->base);
+ return ww_mutex_base_is_locked(&lock->base);
}
#endif
diff --git a/kernel/Kconfig.locks b/kernel/Kconfig.locks
index 3de8fd11873b..4198f0273ecd 100644
--- a/kernel/Kconfig.locks
+++ b/kernel/Kconfig.locks
@@ -251,7 +251,7 @@ config ARCH_USE_QUEUED_RWLOCKS
config QUEUED_RWLOCKS
def_bool y if ARCH_USE_QUEUED_RWLOCKS
- depends on SMP
+ depends on SMP && !PREEMPT_RT
config ARCH_HAS_MMIOWB
bool
diff --git a/kernel/futex.c b/kernel/futex.c
index 2ecb07575055..e7b4c6121da4 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -179,7 +179,7 @@ struct futex_pi_state {
/*
* The PI object:
*/
- struct rt_mutex pi_mutex;
+ struct rt_mutex_base pi_mutex;
struct task_struct *owner;
refcount_t refcount;
@@ -197,6 +197,8 @@ struct futex_pi_state {
* @rt_waiter: rt_waiter storage for use with requeue_pi
* @requeue_pi_key: the requeue_pi target futex key
* @bitset: bitset for the optional bitmasked wakeup
+ * @requeue_state: State field for futex_requeue_pi()
+ * @requeue_wait: RCU wait for futex_requeue_pi() (RT only)
*
* We use this hashed waitqueue, instead of a normal wait_queue_entry_t, so
* we can wake only the relevant ones (hashed queues may be shared).
@@ -219,12 +221,68 @@ struct futex_q {
struct rt_mutex_waiter *rt_waiter;
union futex_key *requeue_pi_key;
u32 bitset;
+ atomic_t requeue_state;
+#ifdef CONFIG_PREEMPT_RT
+ struct rcuwait requeue_wait;
+#endif
} __randomize_layout;
+/*
+ * On PREEMPT_RT, the hash bucket lock is a 'sleeping' spinlock with an
+ * underlying rtmutex. The task which is about to be requeued could have
+ * just woken up (timeout, signal). After the wake up the task has to
+ * acquire hash bucket lock, which is held by the requeue code. As a task
+ * can only be blocked on _ONE_ rtmutex at a time, the proxy lock blocking
+ * and the hash bucket lock blocking would collide and corrupt state.
+ *
+ * On !PREEMPT_RT this is not a problem and everything could be serialized
+ * on hash bucket lock, but aside of having the benefit of common code,
+ * this allows to avoid doing the requeue when the task is already on the
+ * way out and taking the hash bucket lock of the original uaddr1 when the
+ * requeue has been completed.
+ *
+ * The following state transitions are valid:
+ *
+ * On the waiter side:
+ * Q_REQUEUE_PI_NONE -> Q_REQUEUE_PI_IGNORE
+ * Q_REQUEUE_PI_IN_PROGRESS -> Q_REQUEUE_PI_WAIT
+ *
+ * On the requeue side:
+ * Q_REQUEUE_PI_NONE -> Q_REQUEUE_PI_INPROGRESS
+ * Q_REQUEUE_PI_IN_PROGRESS -> Q_REQUEUE_PI_DONE/LOCKED
+ * Q_REQUEUE_PI_IN_PROGRESS -> Q_REQUEUE_PI_NONE (requeue failed)
+ * Q_REQUEUE_PI_WAIT -> Q_REQUEUE_PI_DONE/LOCKED
+ * Q_REQUEUE_PI_WAIT -> Q_REQUEUE_PI_IGNORE (requeue failed)
+ *
+ * The requeue side ignores a waiter with state Q_REQUEUE_PI_IGNORE as this
+ * signals that the waiter is already on the way out. It also means that
+ * the waiter is still on the 'wait' futex, i.e. uaddr1.
+ *
+ * The waiter side signals early wakeup to the requeue side either through
+ * setting state to Q_REQUEUE_PI_IGNORE or to Q_REQUEUE_PI_WAIT depending
+ * on the current state. In case of Q_REQUEUE_PI_IGNORE it can immediately
+ * proceed to take the hash bucket lock of uaddr1. If it set state to WAIT,
+ * which means the wakeup is interleaving with a requeue in progress it has
+ * to wait for the requeue side to change the state. Either to DONE/LOCKED
+ * or to IGNORE. DONE/LOCKED means the waiter q is now on the uaddr2 futex
+ * and either blocked (DONE) or has acquired it (LOCKED). IGNORE is set by
+ * the requeue side when the requeue attempt failed via deadlock detection
+ * and therefore the waiter q is still on the uaddr1 futex.
+ */
+enum {
+ Q_REQUEUE_PI_NONE = 0,
+ Q_REQUEUE_PI_IGNORE,
+ Q_REQUEUE_PI_IN_PROGRESS,
+ Q_REQUEUE_PI_WAIT,
+ Q_REQUEUE_PI_DONE,
+ Q_REQUEUE_PI_LOCKED,
+};
+
static const struct futex_q futex_q_init = {
/* list gets initialized in queue_me()*/
- .key = FUTEX_KEY_INIT,
- .bitset = FUTEX_BITSET_MATCH_ANY
+ .key = FUTEX_KEY_INIT,
+ .bitset = FUTEX_BITSET_MATCH_ANY,
+ .requeue_state = ATOMIC_INIT(Q_REQUEUE_PI_NONE),
};
/*
@@ -1299,27 +1357,6 @@ static int attach_to_pi_owner(u32 __user *uaddr, u32 uval, union futex_key *key,
return 0;
}
-static int lookup_pi_state(u32 __user *uaddr, u32 uval,
- struct futex_hash_bucket *hb,
- union futex_key *key, struct futex_pi_state **ps,
- struct task_struct **exiting)
-{
- struct futex_q *top_waiter = futex_top_waiter(hb, key);
-
- /*
- * If there is a waiter on that futex, validate it and
- * attach to the pi_state when the validation succeeds.
- */
- if (top_waiter)
- return attach_to_pi_state(uaddr, uval, top_waiter->pi_state, ps);
-
- /*
- * We are the first waiter - try to look up the owner based on
- * @uval and attach to it.
- */
- return attach_to_pi_owner(uaddr, uval, key, ps, exiting);
-}
-
static int lock_pi_update_atomic(u32 __user *uaddr, u32 uval, u32 newval)
{
int err;
@@ -1354,7 +1391,7 @@ static int lock_pi_update_atomic(u32 __user *uaddr, u32 uval, u32 newval)
* - 1 - acquired the lock;
* - <0 - error
*
- * The hb->lock and futex_key refs shall be held by the caller.
+ * The hb->lock must be held by the caller.
*
* @exiting is only set when the return value is -EBUSY. If so, this holds
* a refcount on the exiting task on return and the caller needs to drop it
@@ -1493,11 +1530,11 @@ static void mark_wake_futex(struct wake_q_head *wake_q, struct futex_q *q)
*/
static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_state)
{
- u32 curval, newval;
struct rt_mutex_waiter *top_waiter;
struct task_struct *new_owner;
bool postunlock = false;
- DEFINE_WAKE_Q(wake_q);
+ DEFINE_RT_WAKE_Q(wqh);
+ u32 curval, newval;
int ret = 0;
top_waiter = rt_mutex_top_waiter(&pi_state->pi_mutex);
@@ -1549,14 +1586,14 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_
* not fail.
*/
pi_state_update_owner(pi_state, new_owner);
- postunlock = __rt_mutex_futex_unlock(&pi_state->pi_mutex, &wake_q);
+ postunlock = __rt_mutex_futex_unlock(&pi_state->pi_mutex, &wqh);
}
out_unlock:
raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
if (postunlock)
- rt_mutex_postunlock(&wake_q);
+ rt_mutex_postunlock(&wqh);
return ret;
}
@@ -1793,6 +1830,108 @@ void requeue_futex(struct futex_q *q, struct futex_hash_bucket *hb1,
q->key = *key2;
}
+static inline bool futex_requeue_pi_prepare(struct futex_q *q,
+ struct futex_pi_state *pi_state)
+{
+ int old, new;
+
+ /*
+ * Set state to Q_REQUEUE_PI_IN_PROGRESS unless an early wakeup has
+ * already set Q_REQUEUE_PI_IGNORE to signal that requeue should
+ * ignore the waiter.
+ */
+ old = atomic_read_acquire(&q->requeue_state);
+ do {
+ if (old == Q_REQUEUE_PI_IGNORE)
+ return false;
+
+ /*
+ * futex_proxy_trylock_atomic() might have set it to
+ * IN_PROGRESS and a interleaved early wake to WAIT.
+ *
+ * It was considered to have an extra state for that
+ * trylock, but that would just add more conditionals
+ * all over the place for a dubious value.
+ */
+ if (old != Q_REQUEUE_PI_NONE)
+ break;
+
+ new = Q_REQUEUE_PI_IN_PROGRESS;
+ } while (!atomic_try_cmpxchg(&q->requeue_state, &old, new));
+
+ q->pi_state = pi_state;
+ return true;
+}
+
+static inline void futex_requeue_pi_complete(struct futex_q *q, int locked)
+{
+ int old, new;
+
+ old = atomic_read_acquire(&q->requeue_state);
+ do {
+ if (old == Q_REQUEUE_PI_IGNORE)
+ return;
+
+ if (locked >= 0) {
+ /* Requeue succeeded. Set DONE or LOCKED */
+ WARN_ON_ONCE(old != Q_REQUEUE_PI_IN_PROGRESS &&
+ old != Q_REQUEUE_PI_WAIT);
+ new = Q_REQUEUE_PI_DONE + locked;
+ } else if (old == Q_REQUEUE_PI_IN_PROGRESS) {
+ /* Deadlock, no early wakeup interleave */
+ new = Q_REQUEUE_PI_NONE;
+ } else {
+ /* Deadlock, early wakeup interleave. */
+ WARN_ON_ONCE(old != Q_REQUEUE_PI_WAIT);
+ new = Q_REQUEUE_PI_IGNORE;
+ }
+ } while (!atomic_try_cmpxchg(&q->requeue_state, &old, new));
+
+#ifdef CONFIG_PREEMPT_RT
+ /* If the waiter interleaved with the requeue let it know */
+ if (unlikely(old == Q_REQUEUE_PI_WAIT))
+ rcuwait_wake_up(&q->requeue_wait);
+#endif
+}
+
+static inline int futex_requeue_pi_wakeup_sync(struct futex_q *q)
+{
+ int old, new;
+
+ old = atomic_read_acquire(&q->requeue_state);
+ do {
+ /* Is requeue done already? */
+ if (old >= Q_REQUEUE_PI_DONE)
+ return old;
+
+ /*
+ * If not done, then tell the requeue code to either ignore
+ * the waiter or to wake it up once the requeue is done.
+ */
+ new = Q_REQUEUE_PI_WAIT;
+ if (old == Q_REQUEUE_PI_NONE)
+ new = Q_REQUEUE_PI_IGNORE;
+ } while (!atomic_try_cmpxchg(&q->requeue_state, &old, new));
+
+ /* If the requeue was in progress, wait for it to complete */
+ if (old == Q_REQUEUE_PI_IN_PROGRESS) {
+#ifdef CONFIG_PREEMPT_RT
+ rcuwait_wait_event(&q->requeue_wait,
+ atomic_read(&q->requeue_state) != Q_REQUEUE_PI_WAIT,
+ TASK_UNINTERRUPTIBLE);
+#else
+ (void)atomic_cond_read_relaxed(&q->requeue_state, VAL != Q_REQUEUE_PI_WAIT);
+#endif
+ }
+
+ /*
+ * Requeue is now either prohibited or complete. Reread state
+ * because during the wait above it might have changed. Nothing
+ * will modify q->requeue_state after this point.
+ */
+ return atomic_read(&q->requeue_state);
+}
+
/**
* requeue_pi_wake_futex() - Wake a task that acquired the lock during requeue
* @q: the futex_q
@@ -1820,6 +1959,8 @@ void requeue_pi_wake_futex(struct futex_q *q, union futex_key *key,
q->lock_ptr = &hb->lock;
+ /* Signal locked state to the waiter */
+ futex_requeue_pi_complete(q, 1);
wake_up_state(q->task, TASK_NORMAL);
}
@@ -1879,10 +2020,21 @@ futex_proxy_trylock_atomic(u32 __user *pifutex, struct futex_hash_bucket *hb1,
if (!top_waiter)
return 0;
+ /*
+ * Ensure that this is a waiter sitting in futex_wait_requeue_pi()
+ * and waiting on the 'waitqueue' futex which is always !PI.
+ */
+ if (!top_waiter->rt_waiter || top_waiter->pi_state)
+ ret = -EINVAL;
+
/* Ensure we requeue to the expected futex. */
if (!match_futex(top_waiter->requeue_pi_key, key2))
return -EINVAL;
+ /* Ensure that this does not race against an early wakeup */
+ if (!futex_requeue_pi_prepare(top_waiter, NULL))
+ return -EAGAIN;
+
/*
* Try to take the lock for top_waiter. Set the FUTEX_WAITERS bit in
* the contended case or if set_waiters is 1. The pi_state is returned
@@ -1892,8 +2044,22 @@ futex_proxy_trylock_atomic(u32 __user *pifutex, struct futex_hash_bucket *hb1,
ret = futex_lock_pi_atomic(pifutex, hb2, key2, ps, top_waiter->task,
exiting, set_waiters);
if (ret == 1) {
+ /* Dequeue, wake up and update top_waiter::requeue_state */
requeue_pi_wake_futex(top_waiter, key2, hb2);
return vpid;
+ } else if (ret < 0) {
+ /* Rewind top_waiter::requeue_state */
+ futex_requeue_pi_complete(top_waiter, ret);
+ } else {
+ /*
+ * futex_lock_pi_atomic() did not acquire the user space
+ * futex, but managed to establish the proxy lock and pi
+ * state. top_waiter::requeue_state cannot be fixed up here
+ * because the waiter is not enqueued on the rtmutex
+ * yet. This is handled at the callsite depending on the
+ * result of rt_mutex_start_proxy_lock() which is
+ * guaranteed to be reached with this function returning 0.
+ */
}
return ret;
}
@@ -1948,23 +2114,35 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
return -EINVAL;
/*
+ * futex_requeue() allows the caller to define the number
+ * of waiters to wake up via the @nr_wake argument. With
+ * REQUEUE_PI, waking up more than one waiter is creating
+ * more problems than it solves. Waking up a waiter makes
+ * only sense if the PI futex @uaddr2 is uncontended as
+ * this allows the requeue code to acquire the futex
+ * @uaddr2 before waking the waiter. The waiter can then
+ * return to user space without further action. A secondary
+ * wakeup would just make the futex_wait_requeue_pi()
+ * handling more complex, because that code would have to
+ * look up pi_state and do more or less all the handling
+ * which the requeue code has to do for the to be requeued
+ * waiters. So restrict the number of waiters to wake to
+ * one, and only wake it up when the PI futex is
+ * uncontended. Otherwise requeue it and let the unlock of
+ * the PI futex handle the wakeup.
+ *
+ * All REQUEUE_PI users, e.g. pthread_cond_signal() and
+ * pthread_cond_broadcast() must use nr_wake=1.
+ */
+ if (nr_wake != 1)
+ return -EINVAL;
+
+ /*
* requeue_pi requires a pi_state, try to allocate it now
* without any locks in case it fails.
*/
if (refill_pi_state_cache())
return -ENOMEM;
- /*
- * requeue_pi must wake as many tasks as it can, up to nr_wake
- * + nr_requeue, since it acquires the rt_mutex prior to
- * returning to userspace, so as to not leave the rt_mutex with
- * waiters and no owner. However, second and third wake-ups
- * cannot be predicted as they involve race conditions with the
- * first wake and a fault while looking up the pi_state. Both
- * pthread_cond_signal() and pthread_cond_broadcast() should
- * use nr_wake=1.
- */
- if (nr_wake != 1)
- return -EINVAL;
}
retry:
@@ -2014,7 +2192,7 @@ retry_private:
}
}
- if (requeue_pi && (task_count - nr_wake < nr_requeue)) {
+ if (requeue_pi) {
struct task_struct *exiting = NULL;
/*
@@ -2022,6 +2200,8 @@ retry_private:
* intend to requeue waiters, force setting the FUTEX_WAITERS
* bit. We force this here where we are able to easily handle
* faults rather in the requeue loop below.
+ *
+ * Updates topwaiter::requeue_state if a top waiter exists.
*/
ret = futex_proxy_trylock_atomic(uaddr2, hb1, hb2, &key1,
&key2, &pi_state,
@@ -2031,28 +2211,52 @@ retry_private:
* At this point the top_waiter has either taken uaddr2 or is
* waiting on it. If the former, then the pi_state will not
* exist yet, look it up one more time to ensure we have a
- * reference to it. If the lock was taken, ret contains the
- * vpid of the top waiter task.
+ * reference to it. If the lock was taken, @ret contains the
+ * VPID of the top waiter task.
* If the lock was not taken, we have pi_state and an initial
* refcount on it. In case of an error we have nothing.
+ *
+ * The top waiter's requeue_state is up to date:
+ *
+ * - If the lock was acquired atomically (ret > 0), then
+ * the state is Q_REQUEUE_PI_LOCKED.
+ *
+ * - If the trylock failed with an error (ret < 0) then
+ * the state is either Q_REQUEUE_PI_NONE, i.e. "nothing
+ * happened", or Q_REQUEUE_PI_IGNORE when there was an
+ * interleaved early wakeup.
+ *
+ * - If the trylock did not succeed (ret == 0) then the
+ * state is either Q_REQUEUE_PI_IN_PROGRESS or
+ * Q_REQUEUE_PI_WAIT if an early wakeup interleaved.
+ * This will be cleaned up in the loop below, which
+ * cannot fail because futex_proxy_trylock_atomic() did
+ * the same sanity checks for requeue_pi as the loop
+ * below does.
*/
if (ret > 0) {
WARN_ON(pi_state);
task_count++;
/*
- * If we acquired the lock, then the user space value
- * of uaddr2 should be vpid. It cannot be changed by
- * the top waiter as it is blocked on hb2 lock if it
- * tries to do so. If something fiddled with it behind
- * our back the pi state lookup might unearth it. So
- * we rather use the known value than rereading and
- * handing potential crap to lookup_pi_state.
+ * If futex_proxy_trylock_atomic() acquired the
+ * user space futex, then the user space value
+ * @uaddr2 has been set to the @hb1's top waiter
+ * task VPID. This task is guaranteed to be alive
+ * and cannot be exiting because it is either
+ * sleeping or blocked on @hb2 lock.
+ *
+ * The @uaddr2 futex cannot have waiters either as
+ * otherwise futex_proxy_trylock_atomic() would not
+ * have succeeded.
*
- * If that call succeeds then we have pi_state and an
- * initial refcount on it.
+ * In order to requeue waiters to @hb2, pi state is
+ * required. Hand in the VPID value (@ret) and
+ * allocate PI state with an initial refcount on
+ * it.
*/
- ret = lookup_pi_state(uaddr2, ret, hb2, &key2,
- &pi_state, &exiting);
+ ret = attach_to_pi_owner(uaddr2, ret, &key2, &pi_state,
+ &exiting);
+ WARN_ON(ret);
}
switch (ret) {
@@ -2060,7 +2264,10 @@ retry_private:
/* We hold a reference on the pi state. */
break;
- /* If the above failed, then pi_state is NULL */
+ /*
+ * If the above failed, then pi_state is NULL and
+ * waiter::requeue_state is correct.
+ */
case -EFAULT:
double_unlock_hb(hb1, hb2);
hb_waiters_dec(hb2);
@@ -2112,18 +2319,17 @@ retry_private:
break;
}
- /*
- * Wake nr_wake waiters. For requeue_pi, if we acquired the
- * lock, we already woke the top_waiter. If not, it will be
- * woken by futex_unlock_pi().
- */
- if (++task_count <= nr_wake && !requeue_pi) {
- mark_wake_futex(&wake_q, this);
+ /* Plain futexes just wake or requeue and are done */
+ if (!requeue_pi) {
+ if (++task_count <= nr_wake)
+ mark_wake_futex(&wake_q, this);
+ else
+ requeue_futex(this, hb1, hb2, &key2);
continue;
}
/* Ensure we requeue to the expected futex for requeue_pi. */
- if (requeue_pi && !match_futex(this->requeue_pi_key, &key2)) {
+ if (!match_futex(this->requeue_pi_key, &key2)) {
ret = -EINVAL;
break;
}
@@ -2131,54 +2337,67 @@ retry_private:
/*
* Requeue nr_requeue waiters and possibly one more in the case
* of requeue_pi if we couldn't acquire the lock atomically.
+ *
+ * Prepare the waiter to take the rt_mutex. Take a refcount
+ * on the pi_state and store the pointer in the futex_q
+ * object of the waiter.
*/
- if (requeue_pi) {
+ get_pi_state(pi_state);
+
+ /* Don't requeue when the waiter is already on the way out. */
+ if (!futex_requeue_pi_prepare(this, pi_state)) {
/*
- * Prepare the waiter to take the rt_mutex. Take a
- * refcount on the pi_state and store the pointer in
- * the futex_q object of the waiter.
+ * Early woken waiter signaled that it is on the
+ * way out. Drop the pi_state reference and try the
+ * next waiter. @this->pi_state is still NULL.
*/
- get_pi_state(pi_state);
- this->pi_state = pi_state;
- ret = rt_mutex_start_proxy_lock(&pi_state->pi_mutex,
- this->rt_waiter,
- this->task);
- if (ret == 1) {
- /*
- * We got the lock. We do neither drop the
- * refcount on pi_state nor clear
- * this->pi_state because the waiter needs the
- * pi_state for cleaning up the user space
- * value. It will drop the refcount after
- * doing so.
- */
- requeue_pi_wake_futex(this, &key2, hb2);
- continue;
- } else if (ret) {
- /*
- * rt_mutex_start_proxy_lock() detected a
- * potential deadlock when we tried to queue
- * that waiter. Drop the pi_state reference
- * which we took above and remove the pointer
- * to the state from the waiters futex_q
- * object.
- */
- this->pi_state = NULL;
- put_pi_state(pi_state);
- /*
- * We stop queueing more waiters and let user
- * space deal with the mess.
- */
- break;
- }
+ put_pi_state(pi_state);
+ continue;
+ }
+
+ ret = rt_mutex_start_proxy_lock(&pi_state->pi_mutex,
+ this->rt_waiter,
+ this->task);
+
+ if (ret == 1) {
+ /*
+ * We got the lock. We do neither drop the refcount
+ * on pi_state nor clear this->pi_state because the
+ * waiter needs the pi_state for cleaning up the
+ * user space value. It will drop the refcount
+ * after doing so. this::requeue_state is updated
+ * in the wakeup as well.
+ */
+ requeue_pi_wake_futex(this, &key2, hb2);
+ task_count++;
+ } else if (!ret) {
+ /* Waiter is queued, move it to hb2 */
+ requeue_futex(this, hb1, hb2, &key2);
+ futex_requeue_pi_complete(this, 0);
+ task_count++;
+ } else {
+ /*
+ * rt_mutex_start_proxy_lock() detected a potential
+ * deadlock when we tried to queue that waiter.
+ * Drop the pi_state reference which we took above
+ * and remove the pointer to the state from the
+ * waiters futex_q object.
+ */
+ this->pi_state = NULL;
+ put_pi_state(pi_state);
+ futex_requeue_pi_complete(this, ret);
+ /*
+ * We stop queueing more waiters and let user space
+ * deal with the mess.
+ */
+ break;
}
- requeue_futex(this, hb1, hb2, &key2);
}
/*
- * We took an extra initial reference to the pi_state either
- * in futex_proxy_trylock_atomic() or in lookup_pi_state(). We
- * need to drop it here again.
+ * We took an extra initial reference to the pi_state either in
+ * futex_proxy_trylock_atomic() or in attach_to_pi_owner(). We need
+ * to drop it here again.
*/
put_pi_state(pi_state);
@@ -2357,7 +2576,7 @@ static int __fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q,
* Modifying pi_state _before_ the user space value would leave the
* pi_state in an inconsistent state when we fault here, because we
* need to drop the locks to handle the fault. This might be observed
- * in the PID check in lookup_pi_state.
+ * in the PID checks when attaching to PI state .
*/
retry:
if (!argowner) {
@@ -2614,8 +2833,7 @@ static void futex_wait_queue_me(struct futex_hash_bucket *hb, struct futex_q *q,
*
* Setup the futex_q and locate the hash_bucket. Get the futex value and
* compare it with the expected value. Handle atomic faults internally.
- * Return with the hb lock held and a q.key reference on success, and unlocked
- * with no q.key reference on failure.
+ * Return with the hb lock held on success, and unlocked on failure.
*
* Return:
* - 0 - uaddr contains val and hb has been locked;
@@ -2693,8 +2911,8 @@ static int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val,
current->timer_slack_ns);
retry:
/*
- * Prepare to wait on uaddr. On success, holds hb lock and increments
- * q.key refs.
+ * Prepare to wait on uaddr. On success, it holds hb->lock and q
+ * is initialized.
*/
ret = futex_wait_setup(uaddr, val, flags, &q, &hb);
if (ret)
@@ -2705,7 +2923,6 @@ retry:
/* If we were woken (and unqueued), we succeeded, whatever. */
ret = 0;
- /* unqueue_me() drops q.key ref */
if (!unqueue_me(&q))
goto out;
ret = -ETIMEDOUT;
@@ -3072,27 +3289,22 @@ pi_faulted:
}
/**
- * handle_early_requeue_pi_wakeup() - Detect early wakeup on the initial futex
+ * handle_early_requeue_pi_wakeup() - Handle early wakeup on the initial futex
* @hb: the hash_bucket futex_q was original enqueued on
* @q: the futex_q woken while waiting to be requeued
- * @key2: the futex_key of the requeue target futex
* @timeout: the timeout associated with the wait (NULL if none)
*
- * Detect if the task was woken on the initial futex as opposed to the requeue
- * target futex. If so, determine if it was a timeout or a signal that caused
- * the wakeup and return the appropriate error code to the caller. Must be
- * called with the hb lock held.
+ * Determine the cause for the early wakeup.
*
* Return:
- * - 0 = no early wakeup detected;
- * - <0 = -ETIMEDOUT or -ERESTARTNOINTR
+ * -EWOULDBLOCK or -ETIMEDOUT or -ERESTARTNOINTR
*/
static inline
int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
- struct futex_q *q, union futex_key *key2,
+ struct futex_q *q,
struct hrtimer_sleeper *timeout)
{
- int ret = 0;
+ int ret;
/*
* With the hb lock held, we avoid races while we process the wakeup.
@@ -3101,22 +3313,21 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
* It can't be requeued from uaddr2 to something else since we don't
* support a PI aware source futex for requeue.
*/
- if (!match_futex(&q->key, key2)) {
- WARN_ON(q->lock_ptr && (&hb->lock != q->lock_ptr));
- /*
- * We were woken prior to requeue by a timeout or a signal.
- * Unqueue the futex_q and determine which it was.
- */
- plist_del(&q->list, &hb->chain);
- hb_waiters_dec(hb);
+ WARN_ON_ONCE(&hb->lock != q->lock_ptr);
- /* Handle spurious wakeups gracefully */
- ret = -EWOULDBLOCK;
- if (timeout && !timeout->task)
- ret = -ETIMEDOUT;
- else if (signal_pending(current))
- ret = -ERESTARTNOINTR;
- }
+ /*
+ * We were woken prior to requeue by a timeout or a signal.
+ * Unqueue the futex_q and determine which it was.
+ */
+ plist_del(&q->list, &hb->chain);
+ hb_waiters_dec(hb);
+
+ /* Handle spurious wakeups gracefully */
+ ret = -EWOULDBLOCK;
+ if (timeout && !timeout->task)
+ ret = -ETIMEDOUT;
+ else if (signal_pending(current))
+ ret = -ERESTARTNOINTR;
return ret;
}
@@ -3169,6 +3380,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
struct futex_hash_bucket *hb;
union futex_key key2 = FUTEX_KEY_INIT;
struct futex_q q = futex_q_init;
+ struct rt_mutex_base *pi_mutex;
int res, ret;
if (!IS_ENABLED(CONFIG_FUTEX_PI))
@@ -3198,8 +3410,8 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
q.requeue_pi_key = &key2;
/*
- * Prepare to wait on uaddr. On success, increments q.key (key1) ref
- * count.
+ * Prepare to wait on uaddr. On success, it holds hb->lock and q
+ * is initialized.
*/
ret = futex_wait_setup(uaddr, val, flags, &q, &hb);
if (ret)
@@ -3218,32 +3430,22 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
/* Queue the futex_q, drop the hb lock, wait for wakeup. */
futex_wait_queue_me(hb, &q, to);
- spin_lock(&hb->lock);
- ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to);
- spin_unlock(&hb->lock);
- if (ret)
- goto out;
-
- /*
- * In order for us to be here, we know our q.key == key2, and since
- * we took the hb->lock above, we also know that futex_requeue() has
- * completed and we no longer have to concern ourselves with a wakeup
- * race with the atomic proxy lock acquisition by the requeue code. The
- * futex_requeue dropped our key1 reference and incremented our key2
- * reference count.
- */
+ switch (futex_requeue_pi_wakeup_sync(&q)) {
+ case Q_REQUEUE_PI_IGNORE:
+ /* The waiter is still on uaddr1 */
+ spin_lock(&hb->lock);
+ ret = handle_early_requeue_pi_wakeup(hb, &q, to);
+ spin_unlock(&hb->lock);
+ break;
- /*
- * Check if the requeue code acquired the second futex for us and do
- * any pertinent fixup.
- */
- if (!q.rt_waiter) {
+ case Q_REQUEUE_PI_LOCKED:
+ /* The requeue acquired the lock */
if (q.pi_state && (q.pi_state->owner != current)) {
spin_lock(q.lock_ptr);
ret = fixup_owner(uaddr2, &q, true);
/*
- * Drop the reference to the pi state which
- * the requeue_pi() code acquired for us.
+ * Drop the reference to the pi state which the
+ * requeue_pi() code acquired for us.
*/
put_pi_state(q.pi_state);
spin_unlock(q.lock_ptr);
@@ -3253,18 +3455,14 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
*/
ret = ret < 0 ? ret : 0;
}
- } else {
- struct rt_mutex *pi_mutex;
+ break;
- /*
- * We have been woken up by futex_unlock_pi(), a timeout, or a
- * signal. futex_unlock_pi() will not destroy the lock_ptr nor
- * the pi_state.
- */
- WARN_ON(!q.pi_state);
+ case Q_REQUEUE_PI_DONE:
+ /* Requeue completed. Current is 'pi_blocked_on' the rtmutex */
pi_mutex = &q.pi_state->pi_mutex;
ret = rt_mutex_wait_proxy_lock(pi_mutex, to, &rt_waiter);
+ /* Current is not longer pi_blocked_on */
spin_lock(q.lock_ptr);
if (ret && !rt_mutex_cleanup_proxy_lock(pi_mutex, &rt_waiter))
ret = 0;
@@ -3284,17 +3482,21 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
unqueue_me_pi(&q);
spin_unlock(q.lock_ptr);
- }
- if (ret == -EINTR) {
- /*
- * We've already been requeued, but cannot restart by calling
- * futex_lock_pi() directly. We could restart this syscall, but
- * it would detect that the user space "val" changed and return
- * -EWOULDBLOCK. Save the overhead of the restart and return
- * -EWOULDBLOCK directly.
- */
- ret = -EWOULDBLOCK;
+ if (ret == -EINTR) {
+ /*
+ * We've already been requeued, but cannot restart
+ * by calling futex_lock_pi() directly. We could
+ * restart this syscall, but it would detect that
+ * the user space "val" changed and return
+ * -EWOULDBLOCK. Save the overhead of the restart
+ * and return -EWOULDBLOCK directly.
+ */
+ ret = -EWOULDBLOCK;
+ }
+ break;
+ default:
+ BUG();
}
out:
diff --git a/kernel/locking/Makefile b/kernel/locking/Makefile
index 3572808223e4..d51cabf28f38 100644
--- a/kernel/locking/Makefile
+++ b/kernel/locking/Makefile
@@ -24,7 +24,8 @@ obj-$(CONFIG_SMP) += spinlock.o
obj-$(CONFIG_LOCK_SPIN_ON_OWNER) += osq_lock.o
obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
obj-$(CONFIG_QUEUED_SPINLOCKS) += qspinlock.o
-obj-$(CONFIG_RT_MUTEXES) += rtmutex.o
+obj-$(CONFIG_RT_MUTEXES) += rtmutex_api.o
+obj-$(CONFIG_PREEMPT_RT) += spinlock_rt.o ww_rt_mutex.o
obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock_debug.o
obj-$(CONFIG_QUEUED_RWLOCKS) += qrwlock.o
diff --git a/kernel/locking/mutex-debug.c b/kernel/locking/mutex-debug.c
index db9301591e3f..bc8abb8549d2 100644
--- a/kernel/locking/mutex-debug.c
+++ b/kernel/locking/mutex-debug.c
@@ -1,6 +1,4 @@
/*
- * kernel/mutex-debug.c
- *
* Debugging code for mutexes
*
* Started by Ingo Molnar:
@@ -22,7 +20,7 @@
#include <linux/interrupt.h>
#include <linux/debug_locks.h>
-#include "mutex-debug.h"
+#include "mutex.h"
/*
* Must be called with lock->wait_lock held.
@@ -32,6 +30,7 @@ void debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter)
memset(waiter, MUTEX_DEBUG_INIT, sizeof(*waiter));
waiter->magic = waiter;
INIT_LIST_HEAD(&waiter->list);
+ waiter->ww_ctx = MUTEX_POISON_WW_CTX;
}
void debug_mutex_wake_waiter(struct mutex *lock, struct mutex_waiter *waiter)
diff --git a/kernel/locking/mutex-debug.h b/kernel/locking/mutex-debug.h
deleted file mode 100644
index 53e631e1d76d..000000000000
--- a/kernel/locking/mutex-debug.h
+++ /dev/null
@@ -1,29 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * Mutexes: blocking mutual exclusion locks
- *
- * started by Ingo Molnar:
- *
- * Copyright (C) 2004, 2005, 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
- *
- * This file contains mutex debugging related internal declarations,
- * prototypes and inline functions, for the CONFIG_DEBUG_MUTEXES case.
- * More details are in kernel/mutex-debug.c.
- */
-
-/*
- * This must be called with lock->wait_lock held.
- */
-extern void debug_mutex_lock_common(struct mutex *lock,
- struct mutex_waiter *waiter);
-extern void debug_mutex_wake_waiter(struct mutex *lock,
- struct mutex_waiter *waiter);
-extern void debug_mutex_free_waiter(struct mutex_waiter *waiter);
-extern void debug_mutex_add_waiter(struct mutex *lock,
- struct mutex_waiter *waiter,
- struct task_struct *task);
-extern void debug_mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter,
- struct task_struct *task);
-extern void debug_mutex_unlock(struct mutex *lock);
-extern void debug_mutex_init(struct mutex *lock, const char *name,
- struct lock_class_key *key);
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index d2df5e68b503..d456579d0952 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -30,17 +30,20 @@
#include <linux/debug_locks.h>
#include <linux/osq_lock.h>
+#ifndef CONFIG_PREEMPT_RT
+#include "mutex.h"
+
#ifdef CONFIG_DEBUG_MUTEXES
-# include "mutex-debug.h"
+# define MUTEX_WARN_ON(cond) DEBUG_LOCKS_WARN_ON(cond)
#else
-# include "mutex.h"
+# define MUTEX_WARN_ON(cond)
#endif
void
__mutex_init(struct mutex *lock, const char *name, struct lock_class_key *key)
{
atomic_long_set(&lock->owner, 0);
- spin_lock_init(&lock->wait_lock);
+ raw_spin_lock_init(&lock->wait_lock);
INIT_LIST_HEAD(&lock->wait_list);
#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
osq_lock_init(&lock->osq);
@@ -91,55 +94,56 @@ static inline unsigned long __owner_flags(unsigned long owner)
return owner & MUTEX_FLAGS;
}
-/*
- * Trylock variant that returns the owning task on failure.
- */
-static inline struct task_struct *__mutex_trylock_or_owner(struct mutex *lock)
+static inline struct task_struct *__mutex_trylock_common(struct mutex *lock, bool handoff)
{
unsigned long owner, curr = (unsigned long)current;
owner = atomic_long_read(&lock->owner);
for (;;) { /* must loop, can race against a flag */
- unsigned long old, flags = __owner_flags(owner);
+ unsigned long flags = __owner_flags(owner);
unsigned long task = owner & ~MUTEX_FLAGS;
if (task) {
- if (likely(task != curr))
- break;
-
- if (likely(!(flags & MUTEX_FLAG_PICKUP)))
+ if (flags & MUTEX_FLAG_PICKUP) {
+ if (task != curr)
+ break;
+ flags &= ~MUTEX_FLAG_PICKUP;
+ } else if (handoff) {
+ if (flags & MUTEX_FLAG_HANDOFF)
+ break;
+ flags |= MUTEX_FLAG_HANDOFF;
+ } else {
break;
-
- flags &= ~MUTEX_FLAG_PICKUP;
+ }
} else {
-#ifdef CONFIG_DEBUG_MUTEXES
- DEBUG_LOCKS_WARN_ON(flags & MUTEX_FLAG_PICKUP);
-#endif
+ MUTEX_WARN_ON(flags & (MUTEX_FLAG_HANDOFF | MUTEX_FLAG_PICKUP));
+ task = curr;
}
- /*
- * We set the HANDOFF bit, we must make sure it doesn't live
- * past the point where we acquire it. This would be possible
- * if we (accidentally) set the bit on an unlocked mutex.
- */
- flags &= ~MUTEX_FLAG_HANDOFF;
-
- old = atomic_long_cmpxchg_acquire(&lock->owner, owner, curr | flags);
- if (old == owner)
- return NULL;
-
- owner = old;
+ if (atomic_long_try_cmpxchg_acquire(&lock->owner, &owner, task | flags)) {
+ if (task == curr)
+ return NULL;
+ break;
+ }
}
return __owner_task(owner);
}
/*
+ * Trylock or set HANDOFF
+ */
+static inline bool __mutex_trylock_or_handoff(struct mutex *lock, bool handoff)
+{
+ return !__mutex_trylock_common(lock, handoff);
+}
+
+/*
* Actual trylock that will work on any unlocked state.
*/
static inline bool __mutex_trylock(struct mutex *lock)
{
- return !__mutex_trylock_or_owner(lock);
+ return !__mutex_trylock_common(lock, false);
}
#ifndef CONFIG_DEBUG_LOCK_ALLOC
@@ -168,10 +172,7 @@ static __always_inline bool __mutex_unlock_fast(struct mutex *lock)
{
unsigned long curr = (unsigned long)current;
- if (atomic_long_cmpxchg_release(&lock->owner, curr, 0UL) == curr)
- return true;
-
- return false;
+ return atomic_long_try_cmpxchg_release(&lock->owner, &curr, 0UL);
}
#endif
@@ -226,23 +227,18 @@ static void __mutex_handoff(struct mutex *lock, struct task_struct *task)
unsigned long owner = atomic_long_read(&lock->owner);
for (;;) {
- unsigned long old, new;
+ unsigned long new;
-#ifdef CONFIG_DEBUG_MUTEXES
- DEBUG_LOCKS_WARN_ON(__owner_task(owner) != current);
- DEBUG_LOCKS_WARN_ON(owner & MUTEX_FLAG_PICKUP);
-#endif
+ MUTEX_WARN_ON(__owner_task(owner) != current);
+ MUTEX_WARN_ON(owner & MUTEX_FLAG_PICKUP);
new = (owner & MUTEX_FLAG_WAITERS);
new |= (unsigned long)task;
if (task)
new |= MUTEX_FLAG_PICKUP;
- old = atomic_long_cmpxchg_release(&lock->owner, owner, new);
- if (old == owner)
+ if (atomic_long_try_cmpxchg_release(&lock->owner, &owner, new))
break;
-
- owner = old;
}
}
@@ -286,218 +282,18 @@ void __sched mutex_lock(struct mutex *lock)
EXPORT_SYMBOL(mutex_lock);
#endif
-/*
- * Wait-Die:
- * The newer transactions are killed when:
- * It (the new transaction) makes a request for a lock being held
- * by an older transaction.
- *
- * Wound-Wait:
- * The newer transactions are wounded when:
- * An older transaction makes a request for a lock being held by
- * the newer transaction.
- */
-
-/*
- * Associate the ww_mutex @ww with the context @ww_ctx under which we acquired
- * it.
- */
-static __always_inline void
-ww_mutex_lock_acquired(struct ww_mutex *ww, struct ww_acquire_ctx *ww_ctx)
-{
-#ifdef CONFIG_DEBUG_MUTEXES
- /*
- * If this WARN_ON triggers, you used ww_mutex_lock to acquire,
- * but released with a normal mutex_unlock in this call.
- *
- * This should never happen, always use ww_mutex_unlock.
- */
- DEBUG_LOCKS_WARN_ON(ww->ctx);
-
- /*
- * Not quite done after calling ww_acquire_done() ?
- */
- DEBUG_LOCKS_WARN_ON(ww_ctx->done_acquire);
+#include "ww_mutex.h"
- if (ww_ctx->contending_lock) {
- /*
- * After -EDEADLK you tried to
- * acquire a different ww_mutex? Bad!
- */
- DEBUG_LOCKS_WARN_ON(ww_ctx->contending_lock != ww);
-
- /*
- * You called ww_mutex_lock after receiving -EDEADLK,
- * but 'forgot' to unlock everything else first?
- */
- DEBUG_LOCKS_WARN_ON(ww_ctx->acquired > 0);
- ww_ctx->contending_lock = NULL;
- }
-
- /*
- * Naughty, using a different class will lead to undefined behavior!
- */
- DEBUG_LOCKS_WARN_ON(ww_ctx->ww_class != ww->ww_class);
-#endif
- ww_ctx->acquired++;
- ww->ctx = ww_ctx;
-}
-
-/*
- * Determine if context @a is 'after' context @b. IOW, @a is a younger
- * transaction than @b and depending on algorithm either needs to wait for
- * @b or die.
- */
-static inline bool __sched
-__ww_ctx_stamp_after(struct ww_acquire_ctx *a, struct ww_acquire_ctx *b)
-{
-
- return (signed long)(a->stamp - b->stamp) > 0;
-}
-
-/*
- * Wait-Die; wake a younger waiter context (when locks held) such that it can
- * die.
- *
- * Among waiters with context, only the first one can have other locks acquired
- * already (ctx->acquired > 0), because __ww_mutex_add_waiter() and
- * __ww_mutex_check_kill() wake any but the earliest context.
- */
-static bool __sched
-__ww_mutex_die(struct mutex *lock, struct mutex_waiter *waiter,
- struct ww_acquire_ctx *ww_ctx)
-{
- if (!ww_ctx->is_wait_die)
- return false;
-
- if (waiter->ww_ctx->acquired > 0 &&
- __ww_ctx_stamp_after(waiter->ww_ctx, ww_ctx)) {
- debug_mutex_wake_waiter(lock, waiter);
- wake_up_process(waiter->task);
- }
-
- return true;
-}
-
-/*
- * Wound-Wait; wound a younger @hold_ctx if it holds the lock.
- *
- * Wound the lock holder if there are waiters with older transactions than
- * the lock holders. Even if multiple waiters may wound the lock holder,
- * it's sufficient that only one does.
- */
-static bool __ww_mutex_wound(struct mutex *lock,
- struct ww_acquire_ctx *ww_ctx,
- struct ww_acquire_ctx *hold_ctx)
-{
- struct task_struct *owner = __mutex_owner(lock);
-
- lockdep_assert_held(&lock->wait_lock);
-
- /*
- * Possible through __ww_mutex_add_waiter() when we race with
- * ww_mutex_set_context_fastpath(). In that case we'll get here again
- * through __ww_mutex_check_waiters().
- */
- if (!hold_ctx)
- return false;
-
- /*
- * Can have !owner because of __mutex_unlock_slowpath(), but if owner,
- * it cannot go away because we'll have FLAG_WAITERS set and hold
- * wait_lock.
- */
- if (!owner)
- return false;
-
- if (ww_ctx->acquired > 0 && __ww_ctx_stamp_after(hold_ctx, ww_ctx)) {
- hold_ctx->wounded = 1;
-
- /*
- * wake_up_process() paired with set_current_state()
- * inserts sufficient barriers to make sure @owner either sees
- * it's wounded in __ww_mutex_check_kill() or has a
- * wakeup pending to re-read the wounded state.
- */
- if (owner != current)
- wake_up_process(owner);
-
- return true;
- }
-
- return false;
-}
-
-/*
- * We just acquired @lock under @ww_ctx, if there are later contexts waiting
- * behind us on the wait-list, check if they need to die, or wound us.
- *
- * See __ww_mutex_add_waiter() for the list-order construction; basically the
- * list is ordered by stamp, smallest (oldest) first.
- *
- * This relies on never mixing wait-die/wound-wait on the same wait-list;
- * which is currently ensured by that being a ww_class property.
- *
- * The current task must not be on the wait list.
- */
-static void __sched
-__ww_mutex_check_waiters(struct mutex *lock, struct ww_acquire_ctx *ww_ctx)
-{
- struct mutex_waiter *cur;
-
- lockdep_assert_held(&lock->wait_lock);
-
- list_for_each_entry(cur, &lock->wait_list, list) {
- if (!cur->ww_ctx)
- continue;
-
- if (__ww_mutex_die(lock, cur, ww_ctx) ||
- __ww_mutex_wound(lock, cur->ww_ctx, ww_ctx))
- break;
- }
-}
+#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
/*
- * After acquiring lock with fastpath, where we do not hold wait_lock, set ctx
- * and wake up any waiters so they can recheck.
+ * Trylock variant that returns the owning task on failure.
*/
-static __always_inline void
-ww_mutex_set_context_fastpath(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
+static inline struct task_struct *__mutex_trylock_or_owner(struct mutex *lock)
{
- ww_mutex_lock_acquired(lock, ctx);
-
- /*
- * The lock->ctx update should be visible on all cores before
- * the WAITERS check is done, otherwise contended waiters might be
- * missed. The contended waiters will either see ww_ctx == NULL
- * and keep spinning, or it will acquire wait_lock, add itself
- * to waiter list and sleep.
- */
- smp_mb(); /* See comments above and below. */
-
- /*
- * [W] ww->ctx = ctx [W] MUTEX_FLAG_WAITERS
- * MB MB
- * [R] MUTEX_FLAG_WAITERS [R] ww->ctx
- *
- * The memory barrier above pairs with the memory barrier in
- * __ww_mutex_add_waiter() and makes sure we either observe ww->ctx
- * and/or !empty list.
- */
- if (likely(!(atomic_long_read(&lock->base.owner) & MUTEX_FLAG_WAITERS)))
- return;
-
- /*
- * Uh oh, we raced in fastpath, check if any of the waiters need to
- * die or wound us.
- */
- spin_lock(&lock->base.wait_lock);
- __ww_mutex_check_waiters(&lock->base, ctx);
- spin_unlock(&lock->base.wait_lock);
+ return __mutex_trylock_common(lock, false);
}
-#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
-
static inline
bool ww_mutex_spin_on_owner(struct mutex *lock, struct ww_acquire_ctx *ww_ctx,
struct mutex_waiter *waiter)
@@ -754,171 +550,11 @@ EXPORT_SYMBOL(mutex_unlock);
*/
void __sched ww_mutex_unlock(struct ww_mutex *lock)
{
- /*
- * The unlocking fastpath is the 0->1 transition from 'locked'
- * into 'unlocked' state:
- */
- if (lock->ctx) {
-#ifdef CONFIG_DEBUG_MUTEXES
- DEBUG_LOCKS_WARN_ON(!lock->ctx->acquired);
-#endif
- if (lock->ctx->acquired > 0)
- lock->ctx->acquired--;
- lock->ctx = NULL;
- }
-
+ __ww_mutex_unlock(lock);
mutex_unlock(&lock->base);
}
EXPORT_SYMBOL(ww_mutex_unlock);
-
-static __always_inline int __sched
-__ww_mutex_kill(struct mutex *lock, struct ww_acquire_ctx *ww_ctx)
-{
- if (ww_ctx->acquired > 0) {
-#ifdef CONFIG_DEBUG_MUTEXES
- struct ww_mutex *ww;
-
- ww = container_of(lock, struct ww_mutex, base);
- DEBUG_LOCKS_WARN_ON(ww_ctx->contending_lock);
- ww_ctx->contending_lock = ww;
-#endif
- return -EDEADLK;
- }
-
- return 0;
-}
-
-
-/*
- * Check the wound condition for the current lock acquire.
- *
- * Wound-Wait: If we're wounded, kill ourself.
- *
- * Wait-Die: If we're trying to acquire a lock already held by an older
- * context, kill ourselves.
- *
- * Since __ww_mutex_add_waiter() orders the wait-list on stamp, we only have to
- * look at waiters before us in the wait-list.
- */
-static inline int __sched
-__ww_mutex_check_kill(struct mutex *lock, struct mutex_waiter *waiter,
- struct ww_acquire_ctx *ctx)
-{
- struct ww_mutex *ww = container_of(lock, struct ww_mutex, base);
- struct ww_acquire_ctx *hold_ctx = READ_ONCE(ww->ctx);
- struct mutex_waiter *cur;
-
- if (ctx->acquired == 0)
- return 0;
-
- if (!ctx->is_wait_die) {
- if (ctx->wounded)
- return __ww_mutex_kill(lock, ctx);
-
- return 0;
- }
-
- if (hold_ctx && __ww_ctx_stamp_after(ctx, hold_ctx))
- return __ww_mutex_kill(lock, ctx);
-
- /*
- * If there is a waiter in front of us that has a context, then its
- * stamp is earlier than ours and we must kill ourself.
- */
- cur = waiter;
- list_for_each_entry_continue_reverse(cur, &lock->wait_list, list) {
- if (!cur->ww_ctx)
- continue;
-
- return __ww_mutex_kill(lock, ctx);
- }
-
- return 0;
-}
-
-/*
- * Add @waiter to the wait-list, keep the wait-list ordered by stamp, smallest
- * first. Such that older contexts are preferred to acquire the lock over
- * younger contexts.
- *
- * Waiters without context are interspersed in FIFO order.
- *
- * Furthermore, for Wait-Die kill ourself immediately when possible (there are
- * older contexts already waiting) to avoid unnecessary waiting and for
- * Wound-Wait ensure we wound the owning context when it is younger.
- */
-static inline int __sched
-__ww_mutex_add_waiter(struct mutex_waiter *waiter,
- struct mutex *lock,
- struct ww_acquire_ctx *ww_ctx)
-{
- struct mutex_waiter *cur;
- struct list_head *pos;
- bool is_wait_die;
-
- if (!ww_ctx) {
- __mutex_add_waiter(lock, waiter, &lock->wait_list);
- return 0;
- }
-
- is_wait_die = ww_ctx->is_wait_die;
-
- /*
- * Add the waiter before the first waiter with a higher stamp.
- * Waiters without a context are skipped to avoid starving
- * them. Wait-Die waiters may die here. Wound-Wait waiters
- * never die here, but they are sorted in stamp order and
- * may wound the lock holder.
- */
- pos = &lock->wait_list;
- list_for_each_entry_reverse(cur, &lock->wait_list, list) {
- if (!cur->ww_ctx)
- continue;
-
- if (__ww_ctx_stamp_after(ww_ctx, cur->ww_ctx)) {
- /*
- * Wait-Die: if we find an older context waiting, there
- * is no point in queueing behind it, as we'd have to
- * die the moment it would acquire the lock.
- */
- if (is_wait_die) {
- int ret = __ww_mutex_kill(lock, ww_ctx);
-
- if (ret)
- return ret;
- }
-
- break;
- }
-
- pos = &cur->list;
-
- /* Wait-Die: ensure younger waiters die. */
- __ww_mutex_die(lock, cur, ww_ctx);
- }
-
- __mutex_add_waiter(lock, waiter, pos);
-
- /*
- * Wound-Wait: if we're blocking on a mutex owned by a younger context,
- * wound that such that we might proceed.
- */
- if (!is_wait_die) {
- struct ww_mutex *ww = container_of(lock, struct ww_mutex, base);
-
- /*
- * See ww_mutex_set_context_fastpath(). Orders setting
- * MUTEX_FLAG_WAITERS vs the ww->ctx load,
- * such that either we or the fastpath will wound @ww->ctx.
- */
- smp_mb();
- __ww_mutex_wound(lock, ww_ctx, ww->ctx);
- }
-
- return 0;
-}
-
/*
* Lock a mutex (possibly interruptible), slowpath:
*/
@@ -928,7 +564,6 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
struct ww_acquire_ctx *ww_ctx, const bool use_ww_ctx)
{
struct mutex_waiter waiter;
- bool first = false;
struct ww_mutex *ww;
int ret;
@@ -937,9 +572,7 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
might_sleep();
-#ifdef CONFIG_DEBUG_MUTEXES
- DEBUG_LOCKS_WARN_ON(lock->magic != lock);
-#endif
+ MUTEX_WARN_ON(lock->magic != lock);
ww = container_of(lock, struct ww_mutex, base);
if (ww_ctx) {
@@ -953,6 +586,10 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
*/
if (ww_ctx->acquired == 0)
ww_ctx->wounded = 0;
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ nest_lock = &ww_ctx->dep_map;
+#endif
}
preempt_disable();
@@ -968,7 +605,7 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
return 0;
}
- spin_lock(&lock->wait_lock);
+ raw_spin_lock(&lock->wait_lock);
/*
* After waiting to acquire the wait_lock, try again.
*/
@@ -980,17 +617,15 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
}
debug_mutex_lock_common(lock, &waiter);
+ waiter.task = current;
+ if (use_ww_ctx)
+ waiter.ww_ctx = ww_ctx;
lock_contended(&lock->dep_map, ip);
if (!use_ww_ctx) {
/* add waiting tasks to the end of the waitqueue (FIFO): */
__mutex_add_waiter(lock, &waiter, &lock->wait_list);
-
-
-#ifdef CONFIG_DEBUG_MUTEXES
- waiter.ww_ctx = MUTEX_POISON_WW_CTX;
-#endif
} else {
/*
* Add in stamp order, waking up waiters that must kill
@@ -999,14 +634,12 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
ret = __ww_mutex_add_waiter(&waiter, lock, ww_ctx);
if (ret)
goto err_early_kill;
-
- waiter.ww_ctx = ww_ctx;
}
- waiter.task = current;
-
set_current_state(state);
for (;;) {
+ bool first;
+
/*
* Once we hold wait_lock, we're serialized against
* mutex_unlock() handing the lock off to us, do a trylock
@@ -1032,18 +665,10 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
goto err;
}
- spin_unlock(&lock->wait_lock);
+ raw_spin_unlock(&lock->wait_lock);
schedule_preempt_disabled();
- /*
- * ww_mutex needs to always recheck its position since its waiter
- * list is not FIFO ordered.
- */
- if (ww_ctx || !first) {
- first = __mutex_waiter_is_first(lock, &waiter);
- if (first)
- __mutex_set_flag(lock, MUTEX_FLAG_HANDOFF);
- }
+ first = __mutex_waiter_is_first(lock, &waiter);
set_current_state(state);
/*
@@ -1051,13 +676,13 @@ __mutex_lock_common(struct mutex *lock, unsigned int state, unsigned int subclas
* state back to RUNNING and fall through the next schedule(),
* or we must see its unlock and acquire.
*/
- if (__mutex_trylock(lock) ||
+ if (__mutex_trylock_or_handoff(lock, first) ||
(first && mutex_optimistic_spin(lock, ww_ctx, &waiter)))
break;
- spin_lock(&lock->wait_lock);
+ raw_spin_lock(&lock->wait_lock);
}
- spin_lock(&lock->wait_lock);
+ raw_spin_lock(&lock->wait_lock);
acquired:
__set_current_state(TASK_RUNNING);
@@ -1082,7 +707,7 @@ skip_wait:
if (ww_ctx)
ww_mutex_lock_acquired(ww, ww_ctx);
- spin_unlock(&lock->wait_lock);
+ raw_spin_unlock(&lock->wait_lock);
preempt_enable();
return 0;
@@ -1090,7 +715,7 @@ err:
__set_current_state(TASK_RUNNING);
__mutex_remove_waiter(lock, &waiter);
err_early_kill:
- spin_unlock(&lock->wait_lock);
+ raw_spin_unlock(&lock->wait_lock);
debug_mutex_free_waiter(&waiter);
mutex_release(&lock->dep_map, ip);
preempt_enable();
@@ -1106,10 +731,9 @@ __mutex_lock(struct mutex *lock, unsigned int state, unsigned int subclass,
static int __sched
__ww_mutex_lock(struct mutex *lock, unsigned int state, unsigned int subclass,
- struct lockdep_map *nest_lock, unsigned long ip,
- struct ww_acquire_ctx *ww_ctx)
+ unsigned long ip, struct ww_acquire_ctx *ww_ctx)
{
- return __mutex_lock_common(lock, state, subclass, nest_lock, ip, ww_ctx, true);
+ return __mutex_lock_common(lock, state, subclass, NULL, ip, ww_ctx, true);
}
#ifdef CONFIG_DEBUG_LOCK_ALLOC
@@ -1189,8 +813,7 @@ ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
might_sleep();
ret = __ww_mutex_lock(&lock->base, TASK_UNINTERRUPTIBLE,
- 0, ctx ? &ctx->dep_map : NULL, _RET_IP_,
- ctx);
+ 0, _RET_IP_, ctx);
if (!ret && ctx && ctx->acquired > 1)
return ww_mutex_deadlock_injection(lock, ctx);
@@ -1205,8 +828,7 @@ ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
might_sleep();
ret = __ww_mutex_lock(&lock->base, TASK_INTERRUPTIBLE,
- 0, ctx ? &ctx->dep_map : NULL, _RET_IP_,
- ctx);
+ 0, _RET_IP_, ctx);
if (!ret && ctx && ctx->acquired > 1)
return ww_mutex_deadlock_injection(lock, ctx);
@@ -1237,29 +859,21 @@ static noinline void __sched __mutex_unlock_slowpath(struct mutex *lock, unsigne
*/
owner = atomic_long_read(&lock->owner);
for (;;) {
- unsigned long old;
-
-#ifdef CONFIG_DEBUG_MUTEXES
- DEBUG_LOCKS_WARN_ON(__owner_task(owner) != current);
- DEBUG_LOCKS_WARN_ON(owner & MUTEX_FLAG_PICKUP);
-#endif
+ MUTEX_WARN_ON(__owner_task(owner) != current);
+ MUTEX_WARN_ON(owner & MUTEX_FLAG_PICKUP);
if (owner & MUTEX_FLAG_HANDOFF)
break;
- old = atomic_long_cmpxchg_release(&lock->owner, owner,
- __owner_flags(owner));
- if (old == owner) {
+ if (atomic_long_try_cmpxchg_release(&lock->owner, &owner, __owner_flags(owner))) {
if (owner & MUTEX_FLAG_WAITERS)
break;
return;
}
-
- owner = old;
}
- spin_lock(&lock->wait_lock);
+ raw_spin_lock(&lock->wait_lock);
debug_mutex_unlock(lock);
if (!list_empty(&lock->wait_list)) {
/* get the first entry from the wait-list: */
@@ -1276,7 +890,7 @@ static noinline void __sched __mutex_unlock_slowpath(struct mutex *lock, unsigne
if (owner & MUTEX_FLAG_HANDOFF)
__mutex_handoff(lock, next);
- spin_unlock(&lock->wait_lock);
+ raw_spin_unlock(&lock->wait_lock);
wake_up_q(&wake_q);
}
@@ -1380,7 +994,7 @@ __mutex_lock_interruptible_slowpath(struct mutex *lock)
static noinline int __sched
__ww_mutex_lock_slowpath(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
{
- return __ww_mutex_lock(&lock->base, TASK_UNINTERRUPTIBLE, 0, NULL,
+ return __ww_mutex_lock(&lock->base, TASK_UNINTERRUPTIBLE, 0,
_RET_IP_, ctx);
}
@@ -1388,7 +1002,7 @@ static noinline int __sched
__ww_mutex_lock_interruptible_slowpath(struct ww_mutex *lock,
struct ww_acquire_ctx *ctx)
{
- return __ww_mutex_lock(&lock->base, TASK_INTERRUPTIBLE, 0, NULL,
+ return __ww_mutex_lock(&lock->base, TASK_INTERRUPTIBLE, 0,
_RET_IP_, ctx);
}
@@ -1412,9 +1026,7 @@ int __sched mutex_trylock(struct mutex *lock)
{
bool locked;
-#ifdef CONFIG_DEBUG_MUTEXES
- DEBUG_LOCKS_WARN_ON(lock->magic != lock);
-#endif
+ MUTEX_WARN_ON(lock->magic != lock);
locked = __mutex_trylock(lock);
if (locked)
@@ -1455,7 +1067,8 @@ ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
}
EXPORT_SYMBOL(ww_mutex_lock_interruptible);
-#endif
+#endif /* !CONFIG_DEBUG_LOCK_ALLOC */
+#endif /* !CONFIG_PREEMPT_RT */
/**
* atomic_dec_and_mutex_lock - return holding mutex if we dec to 0
diff --git a/kernel/locking/mutex.h b/kernel/locking/mutex.h
index f0c710b1d192..0b2a79c4013b 100644
--- a/kernel/locking/mutex.h
+++ b/kernel/locking/mutex.h
@@ -5,19 +5,41 @@
* started by Ingo Molnar:
*
* Copyright (C) 2004, 2005, 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
- *
- * This file contains mutex debugging related internal prototypes, for the
- * !CONFIG_DEBUG_MUTEXES case. Most of them are NOPs:
*/
-#define debug_mutex_wake_waiter(lock, waiter) do { } while (0)
-#define debug_mutex_free_waiter(waiter) do { } while (0)
-#define debug_mutex_add_waiter(lock, waiter, ti) do { } while (0)
-#define debug_mutex_remove_waiter(lock, waiter, ti) do { } while (0)
-#define debug_mutex_unlock(lock) do { } while (0)
-#define debug_mutex_init(lock, name, key) do { } while (0)
+/*
+ * This is the control structure for tasks blocked on mutex, which resides
+ * on the blocked task's kernel stack:
+ */
+struct mutex_waiter {
+ struct list_head list;
+ struct task_struct *task;
+ struct ww_acquire_ctx *ww_ctx;
+#ifdef CONFIG_DEBUG_MUTEXES
+ void *magic;
+#endif
+};
-static inline void
-debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter)
-{
-}
+#ifdef CONFIG_DEBUG_MUTEXES
+extern void debug_mutex_lock_common(struct mutex *lock,
+ struct mutex_waiter *waiter);
+extern void debug_mutex_wake_waiter(struct mutex *lock,
+ struct mutex_waiter *waiter);
+extern void debug_mutex_free_waiter(struct mutex_waiter *waiter);
+extern void debug_mutex_add_waiter(struct mutex *lock,
+ struct mutex_waiter *waiter,
+ struct task_struct *task);
+extern void debug_mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter,
+ struct task_struct *task);
+extern void debug_mutex_unlock(struct mutex *lock);
+extern void debug_mutex_init(struct mutex *lock, const char *name,
+ struct lock_class_key *key);
+#else /* CONFIG_DEBUG_MUTEXES */
+# define debug_mutex_lock_common(lock, waiter) do { } while (0)
+# define debug_mutex_wake_waiter(lock, waiter) do { } while (0)
+# define debug_mutex_free_waiter(waiter) do { } while (0)
+# define debug_mutex_add_waiter(lock, waiter, ti) do { } while (0)
+# define debug_mutex_remove_waiter(lock, waiter, ti) do { } while (0)
+# define debug_mutex_unlock(lock) do { } while (0)
+# define debug_mutex_init(lock, name, key) do { } while (0)
+#endif /* !CONFIG_DEBUG_MUTEXES */
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index ad0db322ed3b..8eabdc79602b 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -8,20 +8,58 @@
* Copyright (C) 2005-2006 Timesys Corp., Thomas Gleixner <tglx@timesys.com>
* Copyright (C) 2005 Kihon Technologies Inc., Steven Rostedt
* Copyright (C) 2006 Esben Nielsen
+ * Adaptive Spinlocks:
+ * Copyright (C) 2008 Novell, Inc., Gregory Haskins, Sven Dietrich,
+ * and Peter Morreale,
+ * Adaptive Spinlocks simplification:
+ * Copyright (C) 2008 Red Hat, Inc., Steven Rostedt <srostedt@redhat.com>
*
* See Documentation/locking/rt-mutex-design.rst for details.
*/
-#include <linux/spinlock.h>
-#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/deadline.h>
#include <linux/sched/signal.h>
#include <linux/sched/rt.h>
-#include <linux/sched/deadline.h>
#include <linux/sched/wake_q.h>
-#include <linux/sched/debug.h>
-#include <linux/timer.h>
+#include <linux/ww_mutex.h>
#include "rtmutex_common.h"
+#ifndef WW_RT
+# define build_ww_mutex() (false)
+# define ww_container_of(rtm) NULL
+
+static inline int __ww_mutex_add_waiter(struct rt_mutex_waiter *waiter,
+ struct rt_mutex *lock,
+ struct ww_acquire_ctx *ww_ctx)
+{
+ return 0;
+}
+
+static inline void __ww_mutex_check_waiters(struct rt_mutex *lock,
+ struct ww_acquire_ctx *ww_ctx)
+{
+}
+
+static inline void ww_mutex_lock_acquired(struct ww_mutex *lock,
+ struct ww_acquire_ctx *ww_ctx)
+{
+}
+
+static inline int __ww_mutex_check_kill(struct rt_mutex *lock,
+ struct rt_mutex_waiter *waiter,
+ struct ww_acquire_ctx *ww_ctx)
+{
+ return 0;
+}
+
+#else
+# define build_ww_mutex() (true)
+# define ww_container_of(rtm) container_of(rtm, struct ww_mutex, base)
+# include "ww_mutex.h"
+#endif
+
/*
* lock->owner state tracking:
*
@@ -50,7 +88,7 @@
*/
static __always_inline void
-rt_mutex_set_owner(struct rt_mutex *lock, struct task_struct *owner)
+rt_mutex_set_owner(struct rt_mutex_base *lock, struct task_struct *owner)
{
unsigned long val = (unsigned long)owner;
@@ -60,13 +98,13 @@ rt_mutex_set_owner(struct rt_mutex *lock, struct task_struct *owner)
WRITE_ONCE(lock->owner, (struct task_struct *)val);
}
-static __always_inline void clear_rt_mutex_waiters(struct rt_mutex *lock)
+static __always_inline void clear_rt_mutex_waiters(struct rt_mutex_base *lock)
{
lock->owner = (struct task_struct *)
((unsigned long)lock->owner & ~RT_MUTEX_HAS_WAITERS);
}
-static __always_inline void fixup_rt_mutex_waiters(struct rt_mutex *lock)
+static __always_inline void fixup_rt_mutex_waiters(struct rt_mutex_base *lock)
{
unsigned long owner, *p = (unsigned long *) &lock->owner;
@@ -141,15 +179,26 @@ static __always_inline void fixup_rt_mutex_waiters(struct rt_mutex *lock)
* set up.
*/
#ifndef CONFIG_DEBUG_RT_MUTEXES
-# define rt_mutex_cmpxchg_acquire(l,c,n) (cmpxchg_acquire(&l->owner, c, n) == c)
-# define rt_mutex_cmpxchg_release(l,c,n) (cmpxchg_release(&l->owner, c, n) == c)
+static __always_inline bool rt_mutex_cmpxchg_acquire(struct rt_mutex_base *lock,
+ struct task_struct *old,
+ struct task_struct *new)
+{
+ return try_cmpxchg_acquire(&lock->owner, &old, new);
+}
+
+static __always_inline bool rt_mutex_cmpxchg_release(struct rt_mutex_base *lock,
+ struct task_struct *old,
+ struct task_struct *new)
+{
+ return try_cmpxchg_release(&lock->owner, &old, new);
+}
/*
* Callers must hold the ->wait_lock -- which is the whole purpose as we force
* all future threads that attempt to [Rmw] the lock to the slowpath. As such
* relaxed semantics suffice.
*/
-static __always_inline void mark_rt_mutex_waiters(struct rt_mutex *lock)
+static __always_inline void mark_rt_mutex_waiters(struct rt_mutex_base *lock)
{
unsigned long owner, *p = (unsigned long *) &lock->owner;
@@ -165,7 +214,7 @@ static __always_inline void mark_rt_mutex_waiters(struct rt_mutex *lock)
* 2) Drop lock->wait_lock
* 3) Try to unlock the lock with cmpxchg
*/
-static __always_inline bool unlock_rt_mutex_safe(struct rt_mutex *lock,
+static __always_inline bool unlock_rt_mutex_safe(struct rt_mutex_base *lock,
unsigned long flags)
__releases(lock->wait_lock)
{
@@ -201,10 +250,22 @@ static __always_inline bool unlock_rt_mutex_safe(struct rt_mutex *lock,
}
#else
-# define rt_mutex_cmpxchg_acquire(l,c,n) (0)
-# define rt_mutex_cmpxchg_release(l,c,n) (0)
+static __always_inline bool rt_mutex_cmpxchg_acquire(struct rt_mutex_base *lock,
+ struct task_struct *old,
+ struct task_struct *new)
+{
+ return false;
+
+}
-static __always_inline void mark_rt_mutex_waiters(struct rt_mutex *lock)
+static __always_inline bool rt_mutex_cmpxchg_release(struct rt_mutex_base *lock,
+ struct task_struct *old,
+ struct task_struct *new)
+{
+ return false;
+}
+
+static __always_inline void mark_rt_mutex_waiters(struct rt_mutex_base *lock)
{
lock->owner = (struct task_struct *)
((unsigned long)lock->owner | RT_MUTEX_HAS_WAITERS);
@@ -213,7 +274,7 @@ static __always_inline void mark_rt_mutex_waiters(struct rt_mutex *lock)
/*
* Simple slow path only version: lock->owner is protected by lock->wait_lock.
*/
-static __always_inline bool unlock_rt_mutex_safe(struct rt_mutex *lock,
+static __always_inline bool unlock_rt_mutex_safe(struct rt_mutex_base *lock,
unsigned long flags)
__releases(lock->wait_lock)
{
@@ -223,11 +284,28 @@ static __always_inline bool unlock_rt_mutex_safe(struct rt_mutex *lock,
}
#endif
+static __always_inline int __waiter_prio(struct task_struct *task)
+{
+ int prio = task->prio;
+
+ if (!rt_prio(prio))
+ return DEFAULT_PRIO;
+
+ return prio;
+}
+
+static __always_inline void
+waiter_update_prio(struct rt_mutex_waiter *waiter, struct task_struct *task)
+{
+ waiter->prio = __waiter_prio(task);
+ waiter->deadline = task->dl.deadline;
+}
+
/*
* Only use with rt_mutex_waiter_{less,equal}()
*/
#define task_to_waiter(p) \
- &(struct rt_mutex_waiter){ .prio = (p)->prio, .deadline = (p)->dl.deadline }
+ &(struct rt_mutex_waiter){ .prio = __waiter_prio(p), .deadline = (p)->dl.deadline }
static __always_inline int rt_mutex_waiter_less(struct rt_mutex_waiter *left,
struct rt_mutex_waiter *right)
@@ -265,22 +343,63 @@ static __always_inline int rt_mutex_waiter_equal(struct rt_mutex_waiter *left,
return 1;
}
+static inline bool rt_mutex_steal(struct rt_mutex_waiter *waiter,
+ struct rt_mutex_waiter *top_waiter)
+{
+ if (rt_mutex_waiter_less(waiter, top_waiter))
+ return true;
+
+#ifdef RT_MUTEX_BUILD_SPINLOCKS
+ /*
+ * Note that RT tasks are excluded from same priority (lateral)
+ * steals to prevent the introduction of an unbounded latency.
+ */
+ if (rt_prio(waiter->prio) || dl_prio(waiter->prio))
+ return false;
+
+ return rt_mutex_waiter_equal(waiter, top_waiter);
+#else
+ return false;
+#endif
+}
+
#define __node_2_waiter(node) \
rb_entry((node), struct rt_mutex_waiter, tree_entry)
static __always_inline bool __waiter_less(struct rb_node *a, const struct rb_node *b)
{
- return rt_mutex_waiter_less(__node_2_waiter(a), __node_2_waiter(b));
+ struct rt_mutex_waiter *aw = __node_2_waiter(a);
+ struct rt_mutex_waiter *bw = __node_2_waiter(b);
+
+ if (rt_mutex_waiter_less(aw, bw))
+ return 1;
+
+ if (!build_ww_mutex())
+ return 0;
+
+ if (rt_mutex_waiter_less(bw, aw))
+ return 0;
+
+ /* NOTE: relies on waiter->ww_ctx being set before insertion */
+ if (aw->ww_ctx) {
+ if (!bw->ww_ctx)
+ return 1;
+
+ return (signed long)(aw->ww_ctx->stamp -
+ bw->ww_ctx->stamp) < 0;
+ }
+
+ return 0;
}
static __always_inline void
-rt_mutex_enqueue(struct rt_mutex *lock, struct rt_mutex_waiter *waiter)
+rt_mutex_enqueue(struct rt_mutex_base *lock, struct rt_mutex_waiter *waiter)
{
rb_add_cached(&waiter->tree_entry, &lock->waiters, __waiter_less);
}
static __always_inline void
-rt_mutex_dequeue(struct rt_mutex *lock, struct rt_mutex_waiter *waiter)
+rt_mutex_dequeue(struct rt_mutex_base *lock, struct rt_mutex_waiter *waiter)
{
if (RB_EMPTY_NODE(&waiter->tree_entry))
return;
@@ -326,6 +445,35 @@ static __always_inline void rt_mutex_adjust_prio(struct task_struct *p)
rt_mutex_setprio(p, pi_task);
}
+/* RT mutex specific wake_q wrappers */
+static __always_inline void rt_mutex_wake_q_add(struct rt_wake_q_head *wqh,
+ struct rt_mutex_waiter *w)
+{
+ if (IS_ENABLED(CONFIG_PREEMPT_RT) && w->wake_state != TASK_NORMAL) {
+ if (IS_ENABLED(CONFIG_PROVE_LOCKING))
+ WARN_ON_ONCE(wqh->rtlock_task);
+ get_task_struct(w->task);
+ wqh->rtlock_task = w->task;
+ } else {
+ wake_q_add(&wqh->head, w->task);
+ }
+}
+
+static __always_inline void rt_mutex_wake_up_q(struct rt_wake_q_head *wqh)
+{
+ if (IS_ENABLED(CONFIG_PREEMPT_RT) && wqh->rtlock_task) {
+ wake_up_state(wqh->rtlock_task, TASK_RTLOCK_WAIT);
+ put_task_struct(wqh->rtlock_task);
+ wqh->rtlock_task = NULL;
+ }
+
+ if (!wake_q_empty(&wqh->head))
+ wake_up_q(&wqh->head);
+
+ /* Pairs with preempt_disable() in mark_wakeup_next_waiter() */
+ preempt_enable();
+}
+
/*
* Deadlock detection is conditional:
*
@@ -348,12 +496,7 @@ rt_mutex_cond_detect_deadlock(struct rt_mutex_waiter *waiter,
return chwalk == RT_MUTEX_FULL_CHAINWALK;
}
-/*
- * Max number of times we'll walk the boosting chain:
- */
-int max_lock_depth = 1024;
-
-static __always_inline struct rt_mutex *task_blocked_on_lock(struct task_struct *p)
+static __always_inline struct rt_mutex_base *task_blocked_on_lock(struct task_struct *p)
{
return p->pi_blocked_on ? p->pi_blocked_on->lock : NULL;
}
@@ -423,15 +566,15 @@ static __always_inline struct rt_mutex *task_blocked_on_lock(struct task_struct
*/
static int __sched rt_mutex_adjust_prio_chain(struct task_struct *task,
enum rtmutex_chainwalk chwalk,
- struct rt_mutex *orig_lock,
- struct rt_mutex *next_lock,
+ struct rt_mutex_base *orig_lock,
+ struct rt_mutex_base *next_lock,
struct rt_mutex_waiter *orig_waiter,
struct task_struct *top_task)
{
struct rt_mutex_waiter *waiter, *top_waiter = orig_waiter;
struct rt_mutex_waiter *prerequeue_top_waiter;
int ret = 0, depth = 0;
- struct rt_mutex *lock;
+ struct rt_mutex_base *lock;
bool detect_deadlock;
bool requeue = true;
@@ -514,6 +657,31 @@ static int __sched rt_mutex_adjust_prio_chain(struct task_struct *task,
goto out_unlock_pi;
/*
+ * There could be 'spurious' loops in the lock graph due to ww_mutex,
+ * consider:
+ *
+ * P1: A, ww_A, ww_B
+ * P2: ww_B, ww_A
+ * P3: A
+ *
+ * P3 should not return -EDEADLK because it gets trapped in the cycle
+ * created by P1 and P2 (which will resolve -- and runs into
+ * max_lock_depth above). Therefore disable detect_deadlock such that
+ * the below termination condition can trigger once all relevant tasks
+ * are boosted.
+ *
+ * Even when we start with ww_mutex we can disable deadlock detection,
+ * since we would supress a ww_mutex induced deadlock at [6] anyway.
+ * Supressing it here however is not sufficient since we might still
+ * hit [6] due to adjustment driven iteration.
+ *
+ * NOTE: if someone were to create a deadlock between 2 ww_classes we'd
+ * utterly fail to report it; lockdep should.
+ */
+ if (IS_ENABLED(CONFIG_PREEMPT_RT) && waiter->ww_ctx && detect_deadlock)
+ detect_deadlock = false;
+
+ /*
* Drop out, when the task has no waiters. Note,
* top_waiter can be NULL, when we are in the deboosting
* mode!
@@ -574,8 +742,21 @@ static int __sched rt_mutex_adjust_prio_chain(struct task_struct *task,
* walk, we detected a deadlock.
*/
if (lock == orig_lock || rt_mutex_owner(lock) == top_task) {
- raw_spin_unlock(&lock->wait_lock);
ret = -EDEADLK;
+
+ /*
+ * When the deadlock is due to ww_mutex; also see above. Don't
+ * report the deadlock and instead let the ww_mutex wound/die
+ * logic pick which of the contending threads gets -EDEADLK.
+ *
+ * NOTE: assumes the cycle only contains a single ww_class; any
+ * other configuration and we fail to report; also, see
+ * lockdep.
+ */
+ if (IS_ENABLED(CONFIG_PREEMPT_RT) && orig_waiter->ww_ctx)
+ ret = 0;
+
+ raw_spin_unlock(&lock->wait_lock);
goto out_unlock_pi;
}
@@ -653,8 +834,7 @@ static int __sched rt_mutex_adjust_prio_chain(struct task_struct *task,
* serializes all pi_waiters access and rb_erase() does not care about
* the values of the node being removed.
*/
- waiter->prio = task->prio;
- waiter->deadline = task->dl.deadline;
+ waiter_update_prio(waiter, task);
rt_mutex_enqueue(lock, waiter);
@@ -676,7 +856,7 @@ static int __sched rt_mutex_adjust_prio_chain(struct task_struct *task,
* to get the lock.
*/
if (prerequeue_top_waiter != rt_mutex_top_waiter(lock))
- wake_up_process(rt_mutex_top_waiter(lock)->task);
+ wake_up_state(waiter->task, waiter->wake_state);
raw_spin_unlock_irq(&lock->wait_lock);
return 0;
}
@@ -779,7 +959,7 @@ static int __sched rt_mutex_adjust_prio_chain(struct task_struct *task,
* callsite called task_blocked_on_lock(), otherwise NULL
*/
static int __sched
-try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
+try_to_take_rt_mutex(struct rt_mutex_base *lock, struct task_struct *task,
struct rt_mutex_waiter *waiter)
{
lockdep_assert_held(&lock->wait_lock);
@@ -815,19 +995,21 @@ try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
* trylock attempt.
*/
if (waiter) {
- /*
- * If waiter is not the highest priority waiter of
- * @lock, give up.
- */
- if (waiter != rt_mutex_top_waiter(lock))
- return 0;
+ struct rt_mutex_waiter *top_waiter = rt_mutex_top_waiter(lock);
/*
- * We can acquire the lock. Remove the waiter from the
- * lock waiters tree.
+ * If waiter is the highest priority waiter of @lock,
+ * or allowed to steal it, take it over.
*/
- rt_mutex_dequeue(lock, waiter);
-
+ if (waiter == top_waiter || rt_mutex_steal(waiter, top_waiter)) {
+ /*
+ * We can acquire the lock. Remove the waiter from the
+ * lock waiters tree.
+ */
+ rt_mutex_dequeue(lock, waiter);
+ } else {
+ return 0;
+ }
} else {
/*
* If the lock has waiters already we check whether @task is
@@ -838,13 +1020,9 @@ try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
* not need to be dequeued.
*/
if (rt_mutex_has_waiters(lock)) {
- /*
- * If @task->prio is greater than or equal to
- * the top waiter priority (kernel view),
- * @task lost.
- */
- if (!rt_mutex_waiter_less(task_to_waiter(task),
- rt_mutex_top_waiter(lock)))
+ /* Check whether the trylock can steal it. */
+ if (!rt_mutex_steal(task_to_waiter(task),
+ rt_mutex_top_waiter(lock)))
return 0;
/*
@@ -897,14 +1075,15 @@ takeit:
*
* This must be called with lock->wait_lock held and interrupts disabled
*/
-static int __sched task_blocks_on_rt_mutex(struct rt_mutex *lock,
+static int __sched task_blocks_on_rt_mutex(struct rt_mutex_base *lock,
struct rt_mutex_waiter *waiter,
struct task_struct *task,
+ struct ww_acquire_ctx *ww_ctx,
enum rtmutex_chainwalk chwalk)
{
struct task_struct *owner = rt_mutex_owner(lock);
struct rt_mutex_waiter *top_waiter = waiter;
- struct rt_mutex *next_lock;
+ struct rt_mutex_base *next_lock;
int chain_walk = 0, res;
lockdep_assert_held(&lock->wait_lock);
@@ -924,8 +1103,7 @@ static int __sched task_blocks_on_rt_mutex(struct rt_mutex *lock,
raw_spin_lock(&task->pi_lock);
waiter->task = task;
waiter->lock = lock;
- waiter->prio = task->prio;
- waiter->deadline = task->dl.deadline;
+ waiter_update_prio(waiter, task);
/* Get the top priority waiter on the lock */
if (rt_mutex_has_waiters(lock))
@@ -936,6 +1114,21 @@ static int __sched task_blocks_on_rt_mutex(struct rt_mutex *lock,
raw_spin_unlock(&task->pi_lock);
+ if (build_ww_mutex() && ww_ctx) {
+ struct rt_mutex *rtm;
+
+ /* Check whether the waiter should back out immediately */
+ rtm = container_of(lock, struct rt_mutex, rtmutex);
+ res = __ww_mutex_add_waiter(waiter, rtm, ww_ctx);
+ if (res) {
+ raw_spin_lock(&task->pi_lock);
+ rt_mutex_dequeue(lock, waiter);
+ task->pi_blocked_on = NULL;
+ raw_spin_unlock(&task->pi_lock);
+ return res;
+ }
+ }
+
if (!owner)
return 0;
@@ -986,8 +1179,8 @@ static int __sched task_blocks_on_rt_mutex(struct rt_mutex *lock,
*
* Called with lock->wait_lock held and interrupts disabled.
*/
-static void __sched mark_wakeup_next_waiter(struct wake_q_head *wake_q,
- struct rt_mutex *lock)
+static void __sched mark_wakeup_next_waiter(struct rt_wake_q_head *wqh,
+ struct rt_mutex_base *lock)
{
struct rt_mutex_waiter *waiter;
@@ -1023,235 +1216,14 @@ static void __sched mark_wakeup_next_waiter(struct wake_q_head *wake_q,
* deboost but before waking our donor task, hence the preempt_disable()
* before unlock.
*
- * Pairs with preempt_enable() in rt_mutex_postunlock();
+ * Pairs with preempt_enable() in rt_mutex_wake_up_q();
*/
preempt_disable();
- wake_q_add(wake_q, waiter->task);
- raw_spin_unlock(&current->pi_lock);
-}
-
-/*
- * Remove a waiter from a lock and give up
- *
- * Must be called with lock->wait_lock held and interrupts disabled. I must
- * have just failed to try_to_take_rt_mutex().
- */
-static void __sched remove_waiter(struct rt_mutex *lock,
- struct rt_mutex_waiter *waiter)
-{
- bool is_top_waiter = (waiter == rt_mutex_top_waiter(lock));
- struct task_struct *owner = rt_mutex_owner(lock);
- struct rt_mutex *next_lock;
-
- lockdep_assert_held(&lock->wait_lock);
-
- raw_spin_lock(&current->pi_lock);
- rt_mutex_dequeue(lock, waiter);
- current->pi_blocked_on = NULL;
+ rt_mutex_wake_q_add(wqh, waiter);
raw_spin_unlock(&current->pi_lock);
-
- /*
- * Only update priority if the waiter was the highest priority
- * waiter of the lock and there is an owner to update.
- */
- if (!owner || !is_top_waiter)
- return;
-
- raw_spin_lock(&owner->pi_lock);
-
- rt_mutex_dequeue_pi(owner, waiter);
-
- if (rt_mutex_has_waiters(lock))
- rt_mutex_enqueue_pi(owner, rt_mutex_top_waiter(lock));
-
- rt_mutex_adjust_prio(owner);
-
- /* Store the lock on which owner is blocked or NULL */
- next_lock = task_blocked_on_lock(owner);
-
- raw_spin_unlock(&owner->pi_lock);
-
- /*
- * Don't walk the chain, if the owner task is not blocked
- * itself.
- */
- if (!next_lock)
- return;
-
- /* gets dropped in rt_mutex_adjust_prio_chain()! */
- get_task_struct(owner);
-
- raw_spin_unlock_irq(&lock->wait_lock);
-
- rt_mutex_adjust_prio_chain(owner, RT_MUTEX_MIN_CHAINWALK, lock,
- next_lock, NULL, current);
-
- raw_spin_lock_irq(&lock->wait_lock);
-}
-
-/*
- * Recheck the pi chain, in case we got a priority setting
- *
- * Called from sched_setscheduler
- */
-void __sched rt_mutex_adjust_pi(struct task_struct *task)
-{
- struct rt_mutex_waiter *waiter;
- struct rt_mutex *next_lock;
- unsigned long flags;
-
- raw_spin_lock_irqsave(&task->pi_lock, flags);
-
- waiter = task->pi_blocked_on;
- if (!waiter || rt_mutex_waiter_equal(waiter, task_to_waiter(task))) {
- raw_spin_unlock_irqrestore(&task->pi_lock, flags);
- return;
- }
- next_lock = waiter->lock;
- raw_spin_unlock_irqrestore(&task->pi_lock, flags);
-
- /* gets dropped in rt_mutex_adjust_prio_chain()! */
- get_task_struct(task);
-
- rt_mutex_adjust_prio_chain(task, RT_MUTEX_MIN_CHAINWALK, NULL,
- next_lock, NULL, task);
}
-void __sched rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
-{
- debug_rt_mutex_init_waiter(waiter);
- RB_CLEAR_NODE(&waiter->pi_tree_entry);
- RB_CLEAR_NODE(&waiter->tree_entry);
- waiter->task = NULL;
-}
-
-/**
- * __rt_mutex_slowlock() - Perform the wait-wake-try-to-take loop
- * @lock: the rt_mutex to take
- * @state: the state the task should block in (TASK_INTERRUPTIBLE
- * or TASK_UNINTERRUPTIBLE)
- * @timeout: the pre-initialized and started timer, or NULL for none
- * @waiter: the pre-initialized rt_mutex_waiter
- *
- * Must be called with lock->wait_lock held and interrupts disabled
- */
-static int __sched __rt_mutex_slowlock(struct rt_mutex *lock, unsigned int state,
- struct hrtimer_sleeper *timeout,
- struct rt_mutex_waiter *waiter)
-{
- int ret = 0;
-
- for (;;) {
- /* Try to acquire the lock: */
- if (try_to_take_rt_mutex(lock, current, waiter))
- break;
-
- if (timeout && !timeout->task) {
- ret = -ETIMEDOUT;
- break;
- }
- if (signal_pending_state(state, current)) {
- ret = -EINTR;
- break;
- }
-
- raw_spin_unlock_irq(&lock->wait_lock);
-
- schedule();
-
- raw_spin_lock_irq(&lock->wait_lock);
- set_current_state(state);
- }
-
- __set_current_state(TASK_RUNNING);
- return ret;
-}
-
-static void __sched rt_mutex_handle_deadlock(int res, int detect_deadlock,
- struct rt_mutex_waiter *w)
-{
- /*
- * If the result is not -EDEADLOCK or the caller requested
- * deadlock detection, nothing to do here.
- */
- if (res != -EDEADLOCK || detect_deadlock)
- return;
-
- /*
- * Yell loudly and stop the task right here.
- */
- WARN(1, "rtmutex deadlock detected\n");
- while (1) {
- set_current_state(TASK_INTERRUPTIBLE);
- schedule();
- }
-}
-
-/*
- * Slow path lock function:
- */
-static int __sched rt_mutex_slowlock(struct rt_mutex *lock, unsigned int state,
- struct hrtimer_sleeper *timeout,
- enum rtmutex_chainwalk chwalk)
-{
- struct rt_mutex_waiter waiter;
- unsigned long flags;
- int ret = 0;
-
- rt_mutex_init_waiter(&waiter);
-
- /*
- * Technically we could use raw_spin_[un]lock_irq() here, but this can
- * be called in early boot if the cmpxchg() fast path is disabled
- * (debug, no architecture support). In this case we will acquire the
- * rtmutex with lock->wait_lock held. But we cannot unconditionally
- * enable interrupts in that early boot case. So we need to use the
- * irqsave/restore variants.
- */
- raw_spin_lock_irqsave(&lock->wait_lock, flags);
-
- /* Try to acquire the lock again: */
- if (try_to_take_rt_mutex(lock, current, NULL)) {
- raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
- return 0;
- }
-
- set_current_state(state);
-
- /* Setup the timer, when timeout != NULL */
- if (unlikely(timeout))
- hrtimer_start_expires(&timeout->timer, HRTIMER_MODE_ABS);
-
- ret = task_blocks_on_rt_mutex(lock, &waiter, current, chwalk);
-
- if (likely(!ret))
- /* sleep on the mutex */
- ret = __rt_mutex_slowlock(lock, state, timeout, &waiter);
-
- if (unlikely(ret)) {
- __set_current_state(TASK_RUNNING);
- remove_waiter(lock, &waiter);
- rt_mutex_handle_deadlock(ret, chwalk, &waiter);
- }
-
- /*
- * try_to_take_rt_mutex() sets the waiter bit
- * unconditionally. We might have to fix that up.
- */
- fixup_rt_mutex_waiters(lock);
-
- raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
-
- /* Remove pending timer: */
- if (unlikely(timeout))
- hrtimer_cancel(&timeout->timer);
-
- debug_rt_mutex_free_waiter(&waiter);
-
- return ret;
-}
-
-static int __sched __rt_mutex_slowtrylock(struct rt_mutex *lock)
+static int __sched __rt_mutex_slowtrylock(struct rt_mutex_base *lock)
{
int ret = try_to_take_rt_mutex(lock, current, NULL);
@@ -1267,7 +1239,7 @@ static int __sched __rt_mutex_slowtrylock(struct rt_mutex *lock)
/*
* Slow path try-lock function:
*/
-static int __sched rt_mutex_slowtrylock(struct rt_mutex *lock)
+static int __sched rt_mutex_slowtrylock(struct rt_mutex_base *lock)
{
unsigned long flags;
int ret;
@@ -1293,25 +1265,20 @@ static int __sched rt_mutex_slowtrylock(struct rt_mutex *lock)
return ret;
}
-/*
- * Performs the wakeup of the top-waiter and re-enables preemption.
- */
-void __sched rt_mutex_postunlock(struct wake_q_head *wake_q)
+static __always_inline int __rt_mutex_trylock(struct rt_mutex_base *lock)
{
- wake_up_q(wake_q);
+ if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
+ return 1;
- /* Pairs with preempt_disable() in mark_wakeup_next_waiter() */
- preempt_enable();
+ return rt_mutex_slowtrylock(lock);
}
/*
* Slow path to release a rt-mutex.
- *
- * Return whether the current task needs to call rt_mutex_postunlock().
*/
-static void __sched rt_mutex_slowunlock(struct rt_mutex *lock)
+static void __sched rt_mutex_slowunlock(struct rt_mutex_base *lock)
{
- DEFINE_WAKE_Q(wake_q);
+ DEFINE_RT_WAKE_Q(wqh);
unsigned long flags;
/* irqsave required to support early boot calls */
@@ -1364,422 +1331,387 @@ static void __sched rt_mutex_slowunlock(struct rt_mutex *lock)
*
* Queue the next waiter for wakeup once we release the wait_lock.
*/
- mark_wakeup_next_waiter(&wake_q, lock);
+ mark_wakeup_next_waiter(&wqh, lock);
raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
- rt_mutex_postunlock(&wake_q);
+ rt_mutex_wake_up_q(&wqh);
}
-/*
- * debug aware fast / slowpath lock,trylock,unlock
- *
- * The atomic acquire/release ops are compiled away, when either the
- * architecture does not support cmpxchg or when debugging is enabled.
- */
-static __always_inline int __rt_mutex_lock(struct rt_mutex *lock, long state,
- unsigned int subclass)
+static __always_inline void __rt_mutex_unlock(struct rt_mutex_base *lock)
{
- int ret;
-
- might_sleep();
- mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
-
- if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
- return 0;
+ if (likely(rt_mutex_cmpxchg_release(lock, current, NULL)))
+ return;
- ret = rt_mutex_slowlock(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK);
- if (ret)
- mutex_release(&lock->dep_map, _RET_IP_);
- return ret;
+ rt_mutex_slowunlock(lock);
}
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-/**
- * rt_mutex_lock_nested - lock a rt_mutex
- *
- * @lock: the rt_mutex to be locked
- * @subclass: the lockdep subclass
- */
-void __sched rt_mutex_lock_nested(struct rt_mutex *lock, unsigned int subclass)
+#ifdef CONFIG_SMP
+static bool rtmutex_spin_on_owner(struct rt_mutex_base *lock,
+ struct rt_mutex_waiter *waiter,
+ struct task_struct *owner)
{
- __rt_mutex_lock(lock, TASK_UNINTERRUPTIBLE, subclass);
-}
-EXPORT_SYMBOL_GPL(rt_mutex_lock_nested);
-
-#else /* !CONFIG_DEBUG_LOCK_ALLOC */
+ bool res = true;
-/**
- * rt_mutex_lock - lock a rt_mutex
- *
- * @lock: the rt_mutex to be locked
- */
-void __sched rt_mutex_lock(struct rt_mutex *lock)
+ rcu_read_lock();
+ for (;;) {
+ /* If owner changed, trylock again. */
+ if (owner != rt_mutex_owner(lock))
+ break;
+ /*
+ * Ensure that @owner is dereferenced after checking that
+ * the lock owner still matches @owner. If that fails,
+ * @owner might point to freed memory. If it still matches,
+ * the rcu_read_lock() ensures the memory stays valid.
+ */
+ barrier();
+ /*
+ * Stop spinning when:
+ * - the lock owner has been scheduled out
+ * - current is not longer the top waiter
+ * - current is requested to reschedule (redundant
+ * for CONFIG_PREEMPT_RCU=y)
+ * - the VCPU on which owner runs is preempted
+ */
+ if (!owner->on_cpu || need_resched() ||
+ rt_mutex_waiter_is_top_waiter(lock, waiter) ||
+ vcpu_is_preempted(task_cpu(owner))) {
+ res = false;
+ break;
+ }
+ cpu_relax();
+ }
+ rcu_read_unlock();
+ return res;
+}
+#else
+static bool rtmutex_spin_on_owner(struct rt_mutex_base *lock,
+ struct rt_mutex_waiter *waiter,
+ struct task_struct *owner)
{
- __rt_mutex_lock(lock, TASK_UNINTERRUPTIBLE, 0);
+ return false;
}
-EXPORT_SYMBOL_GPL(rt_mutex_lock);
#endif
-/**
- * rt_mutex_lock_interruptible - lock a rt_mutex interruptible
- *
- * @lock: the rt_mutex to be locked
- *
- * Returns:
- * 0 on success
- * -EINTR when interrupted by a signal
+#ifdef RT_MUTEX_BUILD_MUTEX
+/*
+ * Functions required for:
+ * - rtmutex, futex on all kernels
+ * - mutex and rwsem substitutions on RT kernels
*/
-int __sched rt_mutex_lock_interruptible(struct rt_mutex *lock)
-{
- return __rt_mutex_lock(lock, TASK_INTERRUPTIBLE, 0);
-}
-EXPORT_SYMBOL_GPL(rt_mutex_lock_interruptible);
-/**
- * rt_mutex_trylock - try to lock a rt_mutex
- *
- * @lock: the rt_mutex to be locked
- *
- * This function can only be called in thread context. It's safe to call it
- * from atomic regions, but not from hard or soft interrupt context.
+/*
+ * Remove a waiter from a lock and give up
*
- * Returns:
- * 1 on success
- * 0 on contention
+ * Must be called with lock->wait_lock held and interrupts disabled. It must
+ * have just failed to try_to_take_rt_mutex().
*/
-int __sched rt_mutex_trylock(struct rt_mutex *lock)
+static void __sched remove_waiter(struct rt_mutex_base *lock,
+ struct rt_mutex_waiter *waiter)
{
- int ret;
+ bool is_top_waiter = (waiter == rt_mutex_top_waiter(lock));
+ struct task_struct *owner = rt_mutex_owner(lock);
+ struct rt_mutex_base *next_lock;
- if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEXES) && WARN_ON_ONCE(!in_task()))
- return 0;
+ lockdep_assert_held(&lock->wait_lock);
+
+ raw_spin_lock(&current->pi_lock);
+ rt_mutex_dequeue(lock, waiter);
+ current->pi_blocked_on = NULL;
+ raw_spin_unlock(&current->pi_lock);
/*
- * No lockdep annotation required because lockdep disables the fast
- * path.
+ * Only update priority if the waiter was the highest priority
+ * waiter of the lock and there is an owner to update.
*/
- if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
- return 1;
-
- ret = rt_mutex_slowtrylock(lock);
- if (ret)
- mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
-
- return ret;
-}
-EXPORT_SYMBOL_GPL(rt_mutex_trylock);
-
-/**
- * rt_mutex_unlock - unlock a rt_mutex
- *
- * @lock: the rt_mutex to be unlocked
- */
-void __sched rt_mutex_unlock(struct rt_mutex *lock)
-{
- mutex_release(&lock->dep_map, _RET_IP_);
- if (likely(rt_mutex_cmpxchg_release(lock, current, NULL)))
+ if (!owner || !is_top_waiter)
return;
- rt_mutex_slowunlock(lock);
-}
-EXPORT_SYMBOL_GPL(rt_mutex_unlock);
+ raw_spin_lock(&owner->pi_lock);
-/*
- * Futex variants, must not use fastpath.
- */
-int __sched rt_mutex_futex_trylock(struct rt_mutex *lock)
-{
- return rt_mutex_slowtrylock(lock);
-}
+ rt_mutex_dequeue_pi(owner, waiter);
-int __sched __rt_mutex_futex_trylock(struct rt_mutex *lock)
-{
- return __rt_mutex_slowtrylock(lock);
-}
+ if (rt_mutex_has_waiters(lock))
+ rt_mutex_enqueue_pi(owner, rt_mutex_top_waiter(lock));
-/**
- * __rt_mutex_futex_unlock - Futex variant, that since futex variants
- * do not use the fast-path, can be simple and will not need to retry.
- *
- * @lock: The rt_mutex to be unlocked
- * @wake_q: The wake queue head from which to get the next lock waiter
- */
-bool __sched __rt_mutex_futex_unlock(struct rt_mutex *lock,
- struct wake_q_head *wake_q)
-{
- lockdep_assert_held(&lock->wait_lock);
+ rt_mutex_adjust_prio(owner);
- debug_rt_mutex_unlock(lock);
+ /* Store the lock on which owner is blocked or NULL */
+ next_lock = task_blocked_on_lock(owner);
- if (!rt_mutex_has_waiters(lock)) {
- lock->owner = NULL;
- return false; /* done */
- }
+ raw_spin_unlock(&owner->pi_lock);
/*
- * We've already deboosted, mark_wakeup_next_waiter() will
- * retain preempt_disabled when we drop the wait_lock, to
- * avoid inversion prior to the wakeup. preempt_disable()
- * therein pairs with rt_mutex_postunlock().
+ * Don't walk the chain, if the owner task is not blocked
+ * itself.
*/
- mark_wakeup_next_waiter(wake_q, lock);
+ if (!next_lock)
+ return;
- return true; /* call postunlock() */
-}
+ /* gets dropped in rt_mutex_adjust_prio_chain()! */
+ get_task_struct(owner);
-void __sched rt_mutex_futex_unlock(struct rt_mutex *lock)
-{
- DEFINE_WAKE_Q(wake_q);
- unsigned long flags;
- bool postunlock;
+ raw_spin_unlock_irq(&lock->wait_lock);
- raw_spin_lock_irqsave(&lock->wait_lock, flags);
- postunlock = __rt_mutex_futex_unlock(lock, &wake_q);
- raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+ rt_mutex_adjust_prio_chain(owner, RT_MUTEX_MIN_CHAINWALK, lock,
+ next_lock, NULL, current);
- if (postunlock)
- rt_mutex_postunlock(&wake_q);
+ raw_spin_lock_irq(&lock->wait_lock);
}
/**
- * __rt_mutex_init - initialize the rt_mutex
- *
- * @lock: The rt_mutex to be initialized
- * @name: The lock name used for debugging
- * @key: The lock class key used for debugging
- *
- * Initialize the rt_mutex to unlocked state.
+ * rt_mutex_slowlock_block() - Perform the wait-wake-try-to-take loop
+ * @lock: the rt_mutex to take
+ * @ww_ctx: WW mutex context pointer
+ * @state: the state the task should block in (TASK_INTERRUPTIBLE
+ * or TASK_UNINTERRUPTIBLE)
+ * @timeout: the pre-initialized and started timer, or NULL for none
+ * @waiter: the pre-initialized rt_mutex_waiter
*
- * Initializing of a locked rt_mutex is not allowed
+ * Must be called with lock->wait_lock held and interrupts disabled
*/
-void __sched __rt_mutex_init(struct rt_mutex *lock, const char *name,
- struct lock_class_key *key)
+static int __sched rt_mutex_slowlock_block(struct rt_mutex_base *lock,
+ struct ww_acquire_ctx *ww_ctx,
+ unsigned int state,
+ struct hrtimer_sleeper *timeout,
+ struct rt_mutex_waiter *waiter)
{
- debug_check_no_locks_freed((void *)lock, sizeof(*lock));
- lockdep_init_map(&lock->dep_map, name, key, 0);
+ struct rt_mutex *rtm = container_of(lock, struct rt_mutex, rtmutex);
+ struct task_struct *owner;
+ int ret = 0;
- __rt_mutex_basic_init(lock);
-}
-EXPORT_SYMBOL_GPL(__rt_mutex_init);
+ for (;;) {
+ /* Try to acquire the lock: */
+ if (try_to_take_rt_mutex(lock, current, waiter))
+ break;
-/**
- * rt_mutex_init_proxy_locked - initialize and lock a rt_mutex on behalf of a
- * proxy owner
- *
- * @lock: the rt_mutex to be locked
- * @proxy_owner:the task to set as owner
- *
- * No locking. Caller has to do serializing itself
- *
- * Special API call for PI-futex support. This initializes the rtmutex and
- * assigns it to @proxy_owner. Concurrent operations on the rtmutex are not
- * possible at this point because the pi_state which contains the rtmutex
- * is not yet visible to other tasks.
- */
-void __sched rt_mutex_init_proxy_locked(struct rt_mutex *lock,
- struct task_struct *proxy_owner)
-{
- __rt_mutex_basic_init(lock);
- rt_mutex_set_owner(lock, proxy_owner);
+ if (timeout && !timeout->task) {
+ ret = -ETIMEDOUT;
+ break;
+ }
+ if (signal_pending_state(state, current)) {
+ ret = -EINTR;
+ break;
+ }
+
+ if (build_ww_mutex() && ww_ctx) {
+ ret = __ww_mutex_check_kill(rtm, waiter, ww_ctx);
+ if (ret)
+ break;
+ }
+
+ if (waiter == rt_mutex_top_waiter(lock))
+ owner = rt_mutex_owner(lock);
+ else
+ owner = NULL;
+ raw_spin_unlock_irq(&lock->wait_lock);
+
+ if (!owner || !rtmutex_spin_on_owner(lock, waiter, owner))
+ schedule();
+
+ raw_spin_lock_irq(&lock->wait_lock);
+ set_current_state(state);
+ }
+
+ __set_current_state(TASK_RUNNING);
+ return ret;
}
-/**
- * rt_mutex_proxy_unlock - release a lock on behalf of owner
- *
- * @lock: the rt_mutex to be locked
- *
- * No locking. Caller has to do serializing itself
- *
- * Special API call for PI-futex support. This merrily cleans up the rtmutex
- * (debugging) state. Concurrent operations on this rt_mutex are not
- * possible because it belongs to the pi_state which is about to be freed
- * and it is not longer visible to other tasks.
- */
-void __sched rt_mutex_proxy_unlock(struct rt_mutex *lock)
+static void __sched rt_mutex_handle_deadlock(int res, int detect_deadlock,
+ struct rt_mutex_waiter *w)
{
- debug_rt_mutex_proxy_unlock(lock);
- rt_mutex_set_owner(lock, NULL);
+ /*
+ * If the result is not -EDEADLOCK or the caller requested
+ * deadlock detection, nothing to do here.
+ */
+ if (res != -EDEADLOCK || detect_deadlock)
+ return;
+
+ if (build_ww_mutex() && w->ww_ctx)
+ return;
+
+ /*
+ * Yell loudly and stop the task right here.
+ */
+ WARN(1, "rtmutex deadlock detected\n");
+ while (1) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule();
+ }
}
/**
- * __rt_mutex_start_proxy_lock() - Start lock acquisition for another task
- * @lock: the rt_mutex to take
- * @waiter: the pre-initialized rt_mutex_waiter
- * @task: the task to prepare
- *
- * Starts the rt_mutex acquire; it enqueues the @waiter and does deadlock
- * detection. It does not wait, see rt_mutex_wait_proxy_lock() for that.
- *
- * NOTE: does _NOT_ remove the @waiter on failure; must either call
- * rt_mutex_wait_proxy_lock() or rt_mutex_cleanup_proxy_lock() after this.
- *
- * Returns:
- * 0 - task blocked on lock
- * 1 - acquired the lock for task, caller should wake it up
- * <0 - error
- *
- * Special API call for PI-futex support.
+ * __rt_mutex_slowlock - Locking slowpath invoked with lock::wait_lock held
+ * @lock: The rtmutex to block lock
+ * @ww_ctx: WW mutex context pointer
+ * @state: The task state for sleeping
+ * @chwalk: Indicator whether full or partial chainwalk is requested
+ * @waiter: Initializer waiter for blocking
*/
-int __sched __rt_mutex_start_proxy_lock(struct rt_mutex *lock,
- struct rt_mutex_waiter *waiter,
- struct task_struct *task)
+static int __sched __rt_mutex_slowlock(struct rt_mutex_base *lock,
+ struct ww_acquire_ctx *ww_ctx,
+ unsigned int state,
+ enum rtmutex_chainwalk chwalk,
+ struct rt_mutex_waiter *waiter)
{
+ struct rt_mutex *rtm = container_of(lock, struct rt_mutex, rtmutex);
+ struct ww_mutex *ww = ww_container_of(rtm);
int ret;
lockdep_assert_held(&lock->wait_lock);
- if (try_to_take_rt_mutex(lock, task, NULL))
- return 1;
+ /* Try to acquire the lock again: */
+ if (try_to_take_rt_mutex(lock, current, NULL)) {
+ if (build_ww_mutex() && ww_ctx) {
+ __ww_mutex_check_waiters(rtm, ww_ctx);
+ ww_mutex_lock_acquired(ww, ww_ctx);
+ }
+ return 0;
+ }
- /* We enforce deadlock detection for futexes */
- ret = task_blocks_on_rt_mutex(lock, waiter, task,
- RT_MUTEX_FULL_CHAINWALK);
+ set_current_state(state);
- if (ret && !rt_mutex_owner(lock)) {
- /*
- * Reset the return value. We might have
- * returned with -EDEADLK and the owner
- * released the lock while we were walking the
- * pi chain. Let the waiter sort it out.
- */
- ret = 0;
+ ret = task_blocks_on_rt_mutex(lock, waiter, current, ww_ctx, chwalk);
+ if (likely(!ret))
+ ret = rt_mutex_slowlock_block(lock, ww_ctx, state, NULL, waiter);
+
+ if (likely(!ret)) {
+ /* acquired the lock */
+ if (build_ww_mutex() && ww_ctx) {
+ if (!ww_ctx->is_wait_die)
+ __ww_mutex_check_waiters(rtm, ww_ctx);
+ ww_mutex_lock_acquired(ww, ww_ctx);
+ }
+ } else {
+ __set_current_state(TASK_RUNNING);
+ remove_waiter(lock, waiter);
+ rt_mutex_handle_deadlock(ret, chwalk, waiter);
}
+ /*
+ * try_to_take_rt_mutex() sets the waiter bit
+ * unconditionally. We might have to fix that up.
+ */
+ fixup_rt_mutex_waiters(lock);
return ret;
}
-/**
- * rt_mutex_start_proxy_lock() - Start lock acquisition for another task
- * @lock: the rt_mutex to take
- * @waiter: the pre-initialized rt_mutex_waiter
- * @task: the task to prepare
- *
- * Starts the rt_mutex acquire; it enqueues the @waiter and does deadlock
- * detection. It does not wait, see rt_mutex_wait_proxy_lock() for that.
- *
- * NOTE: unlike __rt_mutex_start_proxy_lock this _DOES_ remove the @waiter
- * on failure.
- *
- * Returns:
- * 0 - task blocked on lock
- * 1 - acquired the lock for task, caller should wake it up
- * <0 - error
- *
- * Special API call for PI-futex support.
- */
-int __sched rt_mutex_start_proxy_lock(struct rt_mutex *lock,
- struct rt_mutex_waiter *waiter,
- struct task_struct *task)
+static inline int __rt_mutex_slowlock_locked(struct rt_mutex_base *lock,
+ struct ww_acquire_ctx *ww_ctx,
+ unsigned int state)
{
+ struct rt_mutex_waiter waiter;
int ret;
- raw_spin_lock_irq(&lock->wait_lock);
- ret = __rt_mutex_start_proxy_lock(lock, waiter, task);
- if (unlikely(ret))
- remove_waiter(lock, waiter);
- raw_spin_unlock_irq(&lock->wait_lock);
+ rt_mutex_init_waiter(&waiter);
+ waiter.ww_ctx = ww_ctx;
+ ret = __rt_mutex_slowlock(lock, ww_ctx, state, RT_MUTEX_MIN_CHAINWALK,
+ &waiter);
+
+ debug_rt_mutex_free_waiter(&waiter);
return ret;
}
-/**
- * rt_mutex_wait_proxy_lock() - Wait for lock acquisition
- * @lock: the rt_mutex we were woken on
- * @to: the timeout, null if none. hrtimer should already have
- * been started.
- * @waiter: the pre-initialized rt_mutex_waiter
- *
- * Wait for the lock acquisition started on our behalf by
- * rt_mutex_start_proxy_lock(). Upon failure, the caller must call
- * rt_mutex_cleanup_proxy_lock().
- *
- * Returns:
- * 0 - success
- * <0 - error, one of -EINTR, -ETIMEDOUT
- *
- * Special API call for PI-futex support
+/*
+ * rt_mutex_slowlock - Locking slowpath invoked when fast path fails
+ * @lock: The rtmutex to block lock
+ * @ww_ctx: WW mutex context pointer
+ * @state: The task state for sleeping
*/
-int __sched rt_mutex_wait_proxy_lock(struct rt_mutex *lock,
- struct hrtimer_sleeper *to,
- struct rt_mutex_waiter *waiter)
+static int __sched rt_mutex_slowlock(struct rt_mutex_base *lock,
+ struct ww_acquire_ctx *ww_ctx,
+ unsigned int state)
{
+ unsigned long flags;
int ret;
- raw_spin_lock_irq(&lock->wait_lock);
- /* sleep on the mutex */
- set_current_state(TASK_INTERRUPTIBLE);
- ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter);
/*
- * try_to_take_rt_mutex() sets the waiter bit unconditionally. We might
- * have to fix that up.
+ * Technically we could use raw_spin_[un]lock_irq() here, but this can
+ * be called in early boot if the cmpxchg() fast path is disabled
+ * (debug, no architecture support). In this case we will acquire the
+ * rtmutex with lock->wait_lock held. But we cannot unconditionally
+ * enable interrupts in that early boot case. So we need to use the
+ * irqsave/restore variants.
*/
- fixup_rt_mutex_waiters(lock);
- raw_spin_unlock_irq(&lock->wait_lock);
+ raw_spin_lock_irqsave(&lock->wait_lock, flags);
+ ret = __rt_mutex_slowlock_locked(lock, ww_ctx, state);
+ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
return ret;
}
+static __always_inline int __rt_mutex_lock(struct rt_mutex_base *lock,
+ unsigned int state)
+{
+ if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current)))
+ return 0;
+
+ return rt_mutex_slowlock(lock, NULL, state);
+}
+#endif /* RT_MUTEX_BUILD_MUTEX */
+
+#ifdef RT_MUTEX_BUILD_SPINLOCKS
+/*
+ * Functions required for spin/rw_lock substitution on RT kernels
+ */
+
/**
- * rt_mutex_cleanup_proxy_lock() - Cleanup failed lock acquisition
- * @lock: the rt_mutex we were woken on
- * @waiter: the pre-initialized rt_mutex_waiter
- *
- * Attempt to clean up after a failed __rt_mutex_start_proxy_lock() or
- * rt_mutex_wait_proxy_lock().
- *
- * Unless we acquired the lock; we're still enqueued on the wait-list and can
- * in fact still be granted ownership until we're removed. Therefore we can
- * find we are in fact the owner and must disregard the
- * rt_mutex_wait_proxy_lock() failure.
- *
- * Returns:
- * true - did the cleanup, we done.
- * false - we acquired the lock after rt_mutex_wait_proxy_lock() returned,
- * caller should disregards its return value.
- *
- * Special API call for PI-futex support
+ * rtlock_slowlock_locked - Slow path lock acquisition for RT locks
+ * @lock: The underlying RT mutex
*/
-bool __sched rt_mutex_cleanup_proxy_lock(struct rt_mutex *lock,
- struct rt_mutex_waiter *waiter)
+static void __sched rtlock_slowlock_locked(struct rt_mutex_base *lock)
{
- bool cleanup = false;
+ struct rt_mutex_waiter waiter;
+ struct task_struct *owner;
- raw_spin_lock_irq(&lock->wait_lock);
- /*
- * Do an unconditional try-lock, this deals with the lock stealing
- * state where __rt_mutex_futex_unlock() -> mark_wakeup_next_waiter()
- * sets a NULL owner.
- *
- * We're not interested in the return value, because the subsequent
- * test on rt_mutex_owner() will infer that. If the trylock succeeded,
- * we will own the lock and it will have removed the waiter. If we
- * failed the trylock, we're still not owner and we need to remove
- * ourselves.
- */
- try_to_take_rt_mutex(lock, current, waiter);
- /*
- * Unless we're the owner; we're still enqueued on the wait_list.
- * So check if we became owner, if not, take us off the wait_list.
- */
- if (rt_mutex_owner(lock) != current) {
- remove_waiter(lock, waiter);
- cleanup = true;
+ lockdep_assert_held(&lock->wait_lock);
+
+ if (try_to_take_rt_mutex(lock, current, NULL))
+ return;
+
+ rt_mutex_init_rtlock_waiter(&waiter);
+
+ /* Save current state and set state to TASK_RTLOCK_WAIT */
+ current_save_and_set_rtlock_wait_state();
+
+ task_blocks_on_rt_mutex(lock, &waiter, current, NULL, RT_MUTEX_MIN_CHAINWALK);
+
+ for (;;) {
+ /* Try to acquire the lock again */
+ if (try_to_take_rt_mutex(lock, current, &waiter))
+ break;
+
+ if (&waiter == rt_mutex_top_waiter(lock))
+ owner = rt_mutex_owner(lock);
+ else
+ owner = NULL;
+ raw_spin_unlock_irq(&lock->wait_lock);
+
+ if (!owner || !rtmutex_spin_on_owner(lock, &waiter, owner))
+ schedule_rtlock();
+
+ raw_spin_lock_irq(&lock->wait_lock);
+ set_current_state(TASK_RTLOCK_WAIT);
}
+
+ /* Restore the task state */
+ current_restore_rtlock_saved_state();
+
/*
- * try_to_take_rt_mutex() sets the waiter bit unconditionally. We might
- * have to fix that up.
+ * try_to_take_rt_mutex() sets the waiter bit unconditionally.
+ * We might have to fix that up:
*/
fixup_rt_mutex_waiters(lock);
-
- raw_spin_unlock_irq(&lock->wait_lock);
-
- return cleanup;
+ debug_rt_mutex_free_waiter(&waiter);
}
-#ifdef CONFIG_DEBUG_RT_MUTEXES
-void rt_mutex_debug_task_free(struct task_struct *task)
+static __always_inline void __sched rtlock_slowlock(struct rt_mutex_base *lock)
{
- DEBUG_LOCKS_WARN_ON(!RB_EMPTY_ROOT(&task->pi_waiters.rb_root));
- DEBUG_LOCKS_WARN_ON(task->pi_blocked_on);
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&lock->wait_lock, flags);
+ rtlock_slowlock_locked(lock);
+ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
}
-#endif
+
+#endif /* RT_MUTEX_BUILD_SPINLOCKS */
diff --git a/kernel/locking/rtmutex_api.c b/kernel/locking/rtmutex_api.c
new file mode 100644
index 000000000000..5c9299aaabae
--- /dev/null
+++ b/kernel/locking/rtmutex_api.c
@@ -0,0 +1,590 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * rtmutex API
+ */
+#include <linux/spinlock.h>
+#include <linux/export.h>
+
+#define RT_MUTEX_BUILD_MUTEX
+#include "rtmutex.c"
+
+/*
+ * Max number of times we'll walk the boosting chain:
+ */
+int max_lock_depth = 1024;
+
+/*
+ * Debug aware fast / slowpath lock,trylock,unlock
+ *
+ * The atomic acquire/release ops are compiled away, when either the
+ * architecture does not support cmpxchg or when debugging is enabled.
+ */
+static __always_inline int __rt_mutex_lock_common(struct rt_mutex *lock,
+ unsigned int state,
+ unsigned int subclass)
+{
+ int ret;
+
+ might_sleep();
+ mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+ ret = __rt_mutex_lock(&lock->rtmutex, state);
+ if (ret)
+ mutex_release(&lock->dep_map, _RET_IP_);
+ return ret;
+}
+
+void rt_mutex_base_init(struct rt_mutex_base *rtb)
+{
+ __rt_mutex_base_init(rtb);
+}
+EXPORT_SYMBOL(rt_mutex_base_init);
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+/**
+ * rt_mutex_lock_nested - lock a rt_mutex
+ *
+ * @lock: the rt_mutex to be locked
+ * @subclass: the lockdep subclass
+ */
+void __sched rt_mutex_lock_nested(struct rt_mutex *lock, unsigned int subclass)
+{
+ __rt_mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, subclass);
+}
+EXPORT_SYMBOL_GPL(rt_mutex_lock_nested);
+
+#else /* !CONFIG_DEBUG_LOCK_ALLOC */
+
+/**
+ * rt_mutex_lock - lock a rt_mutex
+ *
+ * @lock: the rt_mutex to be locked
+ */
+void __sched rt_mutex_lock(struct rt_mutex *lock)
+{
+ __rt_mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, 0);
+}
+EXPORT_SYMBOL_GPL(rt_mutex_lock);
+#endif
+
+/**
+ * rt_mutex_lock_interruptible - lock a rt_mutex interruptible
+ *
+ * @lock: the rt_mutex to be locked
+ *
+ * Returns:
+ * 0 on success
+ * -EINTR when interrupted by a signal
+ */
+int __sched rt_mutex_lock_interruptible(struct rt_mutex *lock)
+{
+ return __rt_mutex_lock_common(lock, TASK_INTERRUPTIBLE, 0);
+}
+EXPORT_SYMBOL_GPL(rt_mutex_lock_interruptible);
+
+/**
+ * rt_mutex_trylock - try to lock a rt_mutex
+ *
+ * @lock: the rt_mutex to be locked
+ *
+ * This function can only be called in thread context. It's safe to call it
+ * from atomic regions, but not from hard or soft interrupt context.
+ *
+ * Returns:
+ * 1 on success
+ * 0 on contention
+ */
+int __sched rt_mutex_trylock(struct rt_mutex *lock)
+{
+ int ret;
+
+ if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEXES) && WARN_ON_ONCE(!in_task()))
+ return 0;
+
+ ret = __rt_mutex_trylock(&lock->rtmutex);
+ if (ret)
+ mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(rt_mutex_trylock);
+
+/**
+ * rt_mutex_unlock - unlock a rt_mutex
+ *
+ * @lock: the rt_mutex to be unlocked
+ */
+void __sched rt_mutex_unlock(struct rt_mutex *lock)
+{
+ mutex_release(&lock->dep_map, _RET_IP_);
+ __rt_mutex_unlock(&lock->rtmutex);
+}
+EXPORT_SYMBOL_GPL(rt_mutex_unlock);
+
+/*
+ * Futex variants, must not use fastpath.
+ */
+int __sched rt_mutex_futex_trylock(struct rt_mutex_base *lock)
+{
+ return rt_mutex_slowtrylock(lock);
+}
+
+int __sched __rt_mutex_futex_trylock(struct rt_mutex_base *lock)
+{
+ return __rt_mutex_slowtrylock(lock);
+}
+
+/**
+ * __rt_mutex_futex_unlock - Futex variant, that since futex variants
+ * do not use the fast-path, can be simple and will not need to retry.
+ *
+ * @lock: The rt_mutex to be unlocked
+ * @wqh: The wake queue head from which to get the next lock waiter
+ */
+bool __sched __rt_mutex_futex_unlock(struct rt_mutex_base *lock,
+ struct rt_wake_q_head *wqh)
+{
+ lockdep_assert_held(&lock->wait_lock);
+
+ debug_rt_mutex_unlock(lock);
+
+ if (!rt_mutex_has_waiters(lock)) {
+ lock->owner = NULL;
+ return false; /* done */
+ }
+
+ /*
+ * We've already deboosted, mark_wakeup_next_waiter() will
+ * retain preempt_disabled when we drop the wait_lock, to
+ * avoid inversion prior to the wakeup. preempt_disable()
+ * therein pairs with rt_mutex_postunlock().
+ */
+ mark_wakeup_next_waiter(wqh, lock);
+
+ return true; /* call postunlock() */
+}
+
+void __sched rt_mutex_futex_unlock(struct rt_mutex_base *lock)
+{
+ DEFINE_RT_WAKE_Q(wqh);
+ unsigned long flags;
+ bool postunlock;
+
+ raw_spin_lock_irqsave(&lock->wait_lock, flags);
+ postunlock = __rt_mutex_futex_unlock(lock, &wqh);
+ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
+
+ if (postunlock)
+ rt_mutex_postunlock(&wqh);
+}
+
+/**
+ * __rt_mutex_init - initialize the rt_mutex
+ *
+ * @lock: The rt_mutex to be initialized
+ * @name: The lock name used for debugging
+ * @key: The lock class key used for debugging
+ *
+ * Initialize the rt_mutex to unlocked state.
+ *
+ * Initializing of a locked rt_mutex is not allowed
+ */
+void __sched __rt_mutex_init(struct rt_mutex *lock, const char *name,
+ struct lock_class_key *key)
+{
+ debug_check_no_locks_freed((void *)lock, sizeof(*lock));
+ __rt_mutex_base_init(&lock->rtmutex);
+ lockdep_init_map_wait(&lock->dep_map, name, key, 0, LD_WAIT_SLEEP);
+}
+EXPORT_SYMBOL_GPL(__rt_mutex_init);
+
+/**
+ * rt_mutex_init_proxy_locked - initialize and lock a rt_mutex on behalf of a
+ * proxy owner
+ *
+ * @lock: the rt_mutex to be locked
+ * @proxy_owner:the task to set as owner
+ *
+ * No locking. Caller has to do serializing itself
+ *
+ * Special API call for PI-futex support. This initializes the rtmutex and
+ * assigns it to @proxy_owner. Concurrent operations on the rtmutex are not
+ * possible at this point because the pi_state which contains the rtmutex
+ * is not yet visible to other tasks.
+ */
+void __sched rt_mutex_init_proxy_locked(struct rt_mutex_base *lock,
+ struct task_struct *proxy_owner)
+{
+ static struct lock_class_key pi_futex_key;
+
+ __rt_mutex_base_init(lock);
+ /*
+ * On PREEMPT_RT the futex hashbucket spinlock becomes 'sleeping'
+ * and rtmutex based. That causes a lockdep false positive, because
+ * some of the futex functions invoke spin_unlock(&hb->lock) with
+ * the wait_lock of the rtmutex associated to the pi_futex held.
+ * spin_unlock() in turn takes wait_lock of the rtmutex on which
+ * the spinlock is based, which makes lockdep notice a lock
+ * recursion. Give the futex/rtmutex wait_lock a separate key.
+ */
+ lockdep_set_class(&lock->wait_lock, &pi_futex_key);
+ rt_mutex_set_owner(lock, proxy_owner);
+}
+
+/**
+ * rt_mutex_proxy_unlock - release a lock on behalf of owner
+ *
+ * @lock: the rt_mutex to be locked
+ *
+ * No locking. Caller has to do serializing itself
+ *
+ * Special API call for PI-futex support. This just cleans up the rtmutex
+ * (debugging) state. Concurrent operations on this rt_mutex are not
+ * possible because it belongs to the pi_state which is about to be freed
+ * and it is not longer visible to other tasks.
+ */
+void __sched rt_mutex_proxy_unlock(struct rt_mutex_base *lock)
+{
+ debug_rt_mutex_proxy_unlock(lock);
+ rt_mutex_set_owner(lock, NULL);
+}
+
+/**
+ * __rt_mutex_start_proxy_lock() - Start lock acquisition for another task
+ * @lock: the rt_mutex to take
+ * @waiter: the pre-initialized rt_mutex_waiter
+ * @task: the task to prepare
+ *
+ * Starts the rt_mutex acquire; it enqueues the @waiter and does deadlock
+ * detection. It does not wait, see rt_mutex_wait_proxy_lock() for that.
+ *
+ * NOTE: does _NOT_ remove the @waiter on failure; must either call
+ * rt_mutex_wait_proxy_lock() or rt_mutex_cleanup_proxy_lock() after this.
+ *
+ * Returns:
+ * 0 - task blocked on lock
+ * 1 - acquired the lock for task, caller should wake it up
+ * <0 - error
+ *
+ * Special API call for PI-futex support.
+ */
+int __sched __rt_mutex_start_proxy_lock(struct rt_mutex_base *lock,
+ struct rt_mutex_waiter *waiter,
+ struct task_struct *task)
+{
+ int ret;
+
+ lockdep_assert_held(&lock->wait_lock);
+
+ if (try_to_take_rt_mutex(lock, task, NULL))
+ return 1;
+
+ /* We enforce deadlock detection for futexes */
+ ret = task_blocks_on_rt_mutex(lock, waiter, task, NULL,
+ RT_MUTEX_FULL_CHAINWALK);
+
+ if (ret && !rt_mutex_owner(lock)) {
+ /*
+ * Reset the return value. We might have
+ * returned with -EDEADLK and the owner
+ * released the lock while we were walking the
+ * pi chain. Let the waiter sort it out.
+ */
+ ret = 0;
+ }
+
+ return ret;
+}
+
+/**
+ * rt_mutex_start_proxy_lock() - Start lock acquisition for another task
+ * @lock: the rt_mutex to take
+ * @waiter: the pre-initialized rt_mutex_waiter
+ * @task: the task to prepare
+ *
+ * Starts the rt_mutex acquire; it enqueues the @waiter and does deadlock
+ * detection. It does not wait, see rt_mutex_wait_proxy_lock() for that.
+ *
+ * NOTE: unlike __rt_mutex_start_proxy_lock this _DOES_ remove the @waiter
+ * on failure.
+ *
+ * Returns:
+ * 0 - task blocked on lock
+ * 1 - acquired the lock for task, caller should wake it up
+ * <0 - error
+ *
+ * Special API call for PI-futex support.
+ */
+int __sched rt_mutex_start_proxy_lock(struct rt_mutex_base *lock,
+ struct rt_mutex_waiter *waiter,
+ struct task_struct *task)
+{
+ int ret;
+
+ raw_spin_lock_irq(&lock->wait_lock);
+ ret = __rt_mutex_start_proxy_lock(lock, waiter, task);
+ if (unlikely(ret))
+ remove_waiter(lock, waiter);
+ raw_spin_unlock_irq(&lock->wait_lock);
+
+ return ret;
+}
+
+/**
+ * rt_mutex_wait_proxy_lock() - Wait for lock acquisition
+ * @lock: the rt_mutex we were woken on
+ * @to: the timeout, null if none. hrtimer should already have
+ * been started.
+ * @waiter: the pre-initialized rt_mutex_waiter
+ *
+ * Wait for the lock acquisition started on our behalf by
+ * rt_mutex_start_proxy_lock(). Upon failure, the caller must call
+ * rt_mutex_cleanup_proxy_lock().
+ *
+ * Returns:
+ * 0 - success
+ * <0 - error, one of -EINTR, -ETIMEDOUT
+ *
+ * Special API call for PI-futex support
+ */
+int __sched rt_mutex_wait_proxy_lock(struct rt_mutex_base *lock,
+ struct hrtimer_sleeper *to,
+ struct rt_mutex_waiter *waiter)
+{
+ int ret;
+
+ raw_spin_lock_irq(&lock->wait_lock);
+ /* sleep on the mutex */
+ set_current_state(TASK_INTERRUPTIBLE);
+ ret = rt_mutex_slowlock_block(lock, NULL, TASK_INTERRUPTIBLE, to, waiter);
+ /*
+ * try_to_take_rt_mutex() sets the waiter bit unconditionally. We might
+ * have to fix that up.
+ */
+ fixup_rt_mutex_waiters(lock);
+ raw_spin_unlock_irq(&lock->wait_lock);
+
+ return ret;
+}
+
+/**
+ * rt_mutex_cleanup_proxy_lock() - Cleanup failed lock acquisition
+ * @lock: the rt_mutex we were woken on
+ * @waiter: the pre-initialized rt_mutex_waiter
+ *
+ * Attempt to clean up after a failed __rt_mutex_start_proxy_lock() or
+ * rt_mutex_wait_proxy_lock().
+ *
+ * Unless we acquired the lock; we're still enqueued on the wait-list and can
+ * in fact still be granted ownership until we're removed. Therefore we can
+ * find we are in fact the owner and must disregard the
+ * rt_mutex_wait_proxy_lock() failure.
+ *
+ * Returns:
+ * true - did the cleanup, we done.
+ * false - we acquired the lock after rt_mutex_wait_proxy_lock() returned,
+ * caller should disregards its return value.
+ *
+ * Special API call for PI-futex support
+ */
+bool __sched rt_mutex_cleanup_proxy_lock(struct rt_mutex_base *lock,
+ struct rt_mutex_waiter *waiter)
+{
+ bool cleanup = false;
+
+ raw_spin_lock_irq(&lock->wait_lock);
+ /*
+ * Do an unconditional try-lock, this deals with the lock stealing
+ * state where __rt_mutex_futex_unlock() -> mark_wakeup_next_waiter()
+ * sets a NULL owner.
+ *
+ * We're not interested in the return value, because the subsequent
+ * test on rt_mutex_owner() will infer that. If the trylock succeeded,
+ * we will own the lock and it will have removed the waiter. If we
+ * failed the trylock, we're still not owner and we need to remove
+ * ourselves.
+ */
+ try_to_take_rt_mutex(lock, current, waiter);
+ /*
+ * Unless we're the owner; we're still enqueued on the wait_list.
+ * So check if we became owner, if not, take us off the wait_list.
+ */
+ if (rt_mutex_owner(lock) != current) {
+ remove_waiter(lock, waiter);
+ cleanup = true;
+ }
+ /*
+ * try_to_take_rt_mutex() sets the waiter bit unconditionally. We might
+ * have to fix that up.
+ */
+ fixup_rt_mutex_waiters(lock);
+
+ raw_spin_unlock_irq(&lock->wait_lock);
+
+ return cleanup;
+}
+
+/*
+ * Recheck the pi chain, in case we got a priority setting
+ *
+ * Called from sched_setscheduler
+ */
+void __sched rt_mutex_adjust_pi(struct task_struct *task)
+{
+ struct rt_mutex_waiter *waiter;
+ struct rt_mutex_base *next_lock;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&task->pi_lock, flags);
+
+ waiter = task->pi_blocked_on;
+ if (!waiter || rt_mutex_waiter_equal(waiter, task_to_waiter(task))) {
+ raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+ return;
+ }
+ next_lock = waiter->lock;
+ raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+
+ /* gets dropped in rt_mutex_adjust_prio_chain()! */
+ get_task_struct(task);
+
+ rt_mutex_adjust_prio_chain(task, RT_MUTEX_MIN_CHAINWALK, NULL,
+ next_lock, NULL, task);
+}
+
+/*
+ * Performs the wakeup of the top-waiter and re-enables preemption.
+ */
+void __sched rt_mutex_postunlock(struct rt_wake_q_head *wqh)
+{
+ rt_mutex_wake_up_q(wqh);
+}
+
+#ifdef CONFIG_DEBUG_RT_MUTEXES
+void rt_mutex_debug_task_free(struct task_struct *task)
+{
+ DEBUG_LOCKS_WARN_ON(!RB_EMPTY_ROOT(&task->pi_waiters.rb_root));
+ DEBUG_LOCKS_WARN_ON(task->pi_blocked_on);
+}
+#endif
+
+#ifdef CONFIG_PREEMPT_RT
+/* Mutexes */
+void __mutex_rt_init(struct mutex *mutex, const char *name,
+ struct lock_class_key *key)
+{
+ debug_check_no_locks_freed((void *)mutex, sizeof(*mutex));
+ lockdep_init_map_wait(&mutex->dep_map, name, key, 0, LD_WAIT_SLEEP);
+}
+EXPORT_SYMBOL(__mutex_rt_init);
+
+static __always_inline int __mutex_lock_common(struct mutex *lock,
+ unsigned int state,
+ unsigned int subclass,
+ struct lockdep_map *nest_lock,
+ unsigned long ip)
+{
+ int ret;
+
+ might_sleep();
+ mutex_acquire_nest(&lock->dep_map, subclass, 0, nest_lock, ip);
+ ret = __rt_mutex_lock(&lock->rtmutex, state);
+ if (ret)
+ mutex_release(&lock->dep_map, ip);
+ else
+ lock_acquired(&lock->dep_map, ip);
+ return ret;
+}
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void __sched mutex_lock_nested(struct mutex *lock, unsigned int subclass)
+{
+ __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, subclass, NULL, _RET_IP_);
+}
+EXPORT_SYMBOL_GPL(mutex_lock_nested);
+
+void __sched _mutex_lock_nest_lock(struct mutex *lock,
+ struct lockdep_map *nest_lock)
+{
+ __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, 0, nest_lock, _RET_IP_);
+}
+EXPORT_SYMBOL_GPL(_mutex_lock_nest_lock);
+
+int __sched mutex_lock_interruptible_nested(struct mutex *lock,
+ unsigned int subclass)
+{
+ return __mutex_lock_common(lock, TASK_INTERRUPTIBLE, subclass, NULL, _RET_IP_);
+}
+EXPORT_SYMBOL_GPL(mutex_lock_interruptible_nested);
+
+int __sched mutex_lock_killable_nested(struct mutex *lock,
+ unsigned int subclass)
+{
+ return __mutex_lock_common(lock, TASK_KILLABLE, subclass, NULL, _RET_IP_);
+}
+EXPORT_SYMBOL_GPL(mutex_lock_killable_nested);
+
+void __sched mutex_lock_io_nested(struct mutex *lock, unsigned int subclass)
+{
+ int token;
+
+ might_sleep();
+
+ token = io_schedule_prepare();
+ __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, subclass, NULL, _RET_IP_);
+ io_schedule_finish(token);
+}
+EXPORT_SYMBOL_GPL(mutex_lock_io_nested);
+
+#else /* CONFIG_DEBUG_LOCK_ALLOC */
+
+void __sched mutex_lock(struct mutex *lock)
+{
+ __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, 0, NULL, _RET_IP_);
+}
+EXPORT_SYMBOL(mutex_lock);
+
+int __sched mutex_lock_interruptible(struct mutex *lock)
+{
+ return __mutex_lock_common(lock, TASK_INTERRUPTIBLE, 0, NULL, _RET_IP_);
+}
+EXPORT_SYMBOL(mutex_lock_interruptible);
+
+int __sched mutex_lock_killable(struct mutex *lock)
+{
+ return __mutex_lock_common(lock, TASK_KILLABLE, 0, NULL, _RET_IP_);
+}
+EXPORT_SYMBOL(mutex_lock_killable);
+
+void __sched mutex_lock_io(struct mutex *lock)
+{
+ int token = io_schedule_prepare();
+
+ __mutex_lock_common(lock, TASK_UNINTERRUPTIBLE, 0, NULL, _RET_IP_);
+ io_schedule_finish(token);
+}
+EXPORT_SYMBOL(mutex_lock_io);
+#endif /* !CONFIG_DEBUG_LOCK_ALLOC */
+
+int __sched mutex_trylock(struct mutex *lock)
+{
+ int ret;
+
+ if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEXES) && WARN_ON_ONCE(!in_task()))
+ return 0;
+
+ ret = __rt_mutex_trylock(&lock->rtmutex);
+ if (ret)
+ mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+
+ return ret;
+}
+EXPORT_SYMBOL(mutex_trylock);
+
+void __sched mutex_unlock(struct mutex *lock)
+{
+ mutex_release(&lock->dep_map, _RET_IP_);
+ __rt_mutex_unlock(&lock->rtmutex);
+}
+EXPORT_SYMBOL(mutex_unlock);
+
+#endif /* CONFIG_PREEMPT_RT */
diff --git a/kernel/locking/rtmutex_common.h b/kernel/locking/rtmutex_common.h
index a90c22abdbca..c47e8361bfb5 100644
--- a/kernel/locking/rtmutex_common.h
+++ b/kernel/locking/rtmutex_common.h
@@ -25,29 +25,90 @@
* @pi_tree_entry: pi node to enqueue into the mutex owner waiters tree
* @task: task reference to the blocked task
* @lock: Pointer to the rt_mutex on which the waiter blocks
+ * @wake_state: Wakeup state to use (TASK_NORMAL or TASK_RTLOCK_WAIT)
* @prio: Priority of the waiter
* @deadline: Deadline of the waiter if applicable
+ * @ww_ctx: WW context pointer
*/
struct rt_mutex_waiter {
struct rb_node tree_entry;
struct rb_node pi_tree_entry;
struct task_struct *task;
- struct rt_mutex *lock;
+ struct rt_mutex_base *lock;
+ unsigned int wake_state;
int prio;
u64 deadline;
+ struct ww_acquire_ctx *ww_ctx;
};
+/**
+ * rt_wake_q_head - Wrapper around regular wake_q_head to support
+ * "sleeping" spinlocks on RT
+ * @head: The regular wake_q_head for sleeping lock variants
+ * @rtlock_task: Task pointer for RT lock (spin/rwlock) wakeups
+ */
+struct rt_wake_q_head {
+ struct wake_q_head head;
+ struct task_struct *rtlock_task;
+};
+
+#define DEFINE_RT_WAKE_Q(name) \
+ struct rt_wake_q_head name = { \
+ .head = WAKE_Q_HEAD_INITIALIZER(name.head), \
+ .rtlock_task = NULL, \
+ }
+
+/*
+ * PI-futex support (proxy locking functions, etc.):
+ */
+extern void rt_mutex_init_proxy_locked(struct rt_mutex_base *lock,
+ struct task_struct *proxy_owner);
+extern void rt_mutex_proxy_unlock(struct rt_mutex_base *lock);
+extern int __rt_mutex_start_proxy_lock(struct rt_mutex_base *lock,
+ struct rt_mutex_waiter *waiter,
+ struct task_struct *task);
+extern int rt_mutex_start_proxy_lock(struct rt_mutex_base *lock,
+ struct rt_mutex_waiter *waiter,
+ struct task_struct *task);
+extern int rt_mutex_wait_proxy_lock(struct rt_mutex_base *lock,
+ struct hrtimer_sleeper *to,
+ struct rt_mutex_waiter *waiter);
+extern bool rt_mutex_cleanup_proxy_lock(struct rt_mutex_base *lock,
+ struct rt_mutex_waiter *waiter);
+
+extern int rt_mutex_futex_trylock(struct rt_mutex_base *l);
+extern int __rt_mutex_futex_trylock(struct rt_mutex_base *l);
+
+extern void rt_mutex_futex_unlock(struct rt_mutex_base *lock);
+extern bool __rt_mutex_futex_unlock(struct rt_mutex_base *lock,
+ struct rt_wake_q_head *wqh);
+
+extern void rt_mutex_postunlock(struct rt_wake_q_head *wqh);
+
/*
* Must be guarded because this header is included from rcu/tree_plugin.h
* unconditionally.
*/
#ifdef CONFIG_RT_MUTEXES
-static inline int rt_mutex_has_waiters(struct rt_mutex *lock)
+static inline int rt_mutex_has_waiters(struct rt_mutex_base *lock)
{
return !RB_EMPTY_ROOT(&lock->waiters.rb_root);
}
-static inline struct rt_mutex_waiter *rt_mutex_top_waiter(struct rt_mutex *lock)
+/*
+ * Lockless speculative check whether @waiter is still the top waiter on
+ * @lock. This is solely comparing pointers and not derefencing the
+ * leftmost entry which might be about to vanish.
+ */
+static inline bool rt_mutex_waiter_is_top_waiter(struct rt_mutex_base *lock,
+ struct rt_mutex_waiter *waiter)
+{
+ struct rb_node *leftmost = rb_first_cached(&lock->waiters);
+
+ return rb_entry(leftmost, struct rt_mutex_waiter, tree_entry) == waiter;
+}
+
+static inline struct rt_mutex_waiter *rt_mutex_top_waiter(struct rt_mutex_base *lock)
{
struct rb_node *leftmost = rb_first_cached(&lock->waiters);
struct rt_mutex_waiter *w = NULL;
@@ -72,19 +133,12 @@ static inline struct rt_mutex_waiter *task_top_pi_waiter(struct task_struct *p)
#define RT_MUTEX_HAS_WAITERS 1UL
-static inline struct task_struct *rt_mutex_owner(struct rt_mutex *lock)
+static inline struct task_struct *rt_mutex_owner(struct rt_mutex_base *lock)
{
unsigned long owner = (unsigned long) READ_ONCE(lock->owner);
return (struct task_struct *) (owner & ~RT_MUTEX_HAS_WAITERS);
}
-#else /* CONFIG_RT_MUTEXES */
-/* Used in rcu/tree_plugin.h */
-static inline struct task_struct *rt_mutex_owner(struct rt_mutex *lock)
-{
- return NULL;
-}
-#endif /* !CONFIG_RT_MUTEXES */
/*
* Constants for rt mutex functions which have a selectable deadlock
@@ -101,49 +155,21 @@ enum rtmutex_chainwalk {
RT_MUTEX_FULL_CHAINWALK,
};
-static inline void __rt_mutex_basic_init(struct rt_mutex *lock)
+static inline void __rt_mutex_base_init(struct rt_mutex_base *lock)
{
- lock->owner = NULL;
raw_spin_lock_init(&lock->wait_lock);
lock->waiters = RB_ROOT_CACHED;
+ lock->owner = NULL;
}
-/*
- * PI-futex support (proxy locking functions, etc.):
- */
-extern void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
- struct task_struct *proxy_owner);
-extern void rt_mutex_proxy_unlock(struct rt_mutex *lock);
-extern void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter);
-extern int __rt_mutex_start_proxy_lock(struct rt_mutex *lock,
- struct rt_mutex_waiter *waiter,
- struct task_struct *task);
-extern int rt_mutex_start_proxy_lock(struct rt_mutex *lock,
- struct rt_mutex_waiter *waiter,
- struct task_struct *task);
-extern int rt_mutex_wait_proxy_lock(struct rt_mutex *lock,
- struct hrtimer_sleeper *to,
- struct rt_mutex_waiter *waiter);
-extern bool rt_mutex_cleanup_proxy_lock(struct rt_mutex *lock,
- struct rt_mutex_waiter *waiter);
-
-extern int rt_mutex_futex_trylock(struct rt_mutex *l);
-extern int __rt_mutex_futex_trylock(struct rt_mutex *l);
-
-extern void rt_mutex_futex_unlock(struct rt_mutex *lock);
-extern bool __rt_mutex_futex_unlock(struct rt_mutex *lock,
- struct wake_q_head *wqh);
-
-extern void rt_mutex_postunlock(struct wake_q_head *wake_q);
-
/* Debug functions */
-static inline void debug_rt_mutex_unlock(struct rt_mutex *lock)
+static inline void debug_rt_mutex_unlock(struct rt_mutex_base *lock)
{
if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEXES))
DEBUG_LOCKS_WARN_ON(rt_mutex_owner(lock) != current);
}
-static inline void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock)
+static inline void debug_rt_mutex_proxy_unlock(struct rt_mutex_base *lock)
{
if (IS_ENABLED(CONFIG_DEBUG_RT_MUTEXES))
DEBUG_LOCKS_WARN_ON(!rt_mutex_owner(lock));
@@ -161,4 +187,27 @@ static inline void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter)
memset(waiter, 0x22, sizeof(*waiter));
}
+static inline void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
+{
+ debug_rt_mutex_init_waiter(waiter);
+ RB_CLEAR_NODE(&waiter->pi_tree_entry);
+ RB_CLEAR_NODE(&waiter->tree_entry);
+ waiter->wake_state = TASK_NORMAL;
+ waiter->task = NULL;
+}
+
+static inline void rt_mutex_init_rtlock_waiter(struct rt_mutex_waiter *waiter)
+{
+ rt_mutex_init_waiter(waiter);
+ waiter->wake_state = TASK_RTLOCK_WAIT;
+}
+
+#else /* CONFIG_RT_MUTEXES */
+/* Used in rcu/tree_plugin.h */
+static inline struct task_struct *rt_mutex_owner(struct rt_mutex_base *lock)
+{
+ return NULL;
+}
+#endif /* !CONFIG_RT_MUTEXES */
+
#endif
diff --git a/kernel/locking/rwbase_rt.c b/kernel/locking/rwbase_rt.c
new file mode 100644
index 000000000000..4ba15088e640
--- /dev/null
+++ b/kernel/locking/rwbase_rt.c
@@ -0,0 +1,263 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/*
+ * RT-specific reader/writer semaphores and reader/writer locks
+ *
+ * down_write/write_lock()
+ * 1) Lock rtmutex
+ * 2) Remove the reader BIAS to force readers into the slow path
+ * 3) Wait until all readers have left the critical section
+ * 4) Mark it write locked
+ *
+ * up_write/write_unlock()
+ * 1) Remove the write locked marker
+ * 2) Set the reader BIAS, so readers can use the fast path again
+ * 3) Unlock rtmutex, to release blocked readers
+ *
+ * down_read/read_lock()
+ * 1) Try fast path acquisition (reader BIAS is set)
+ * 2) Take tmutex::wait_lock, which protects the writelocked flag
+ * 3) If !writelocked, acquire it for read
+ * 4) If writelocked, block on tmutex
+ * 5) unlock rtmutex, goto 1)
+ *
+ * up_read/read_unlock()
+ * 1) Try fast path release (reader count != 1)
+ * 2) Wake the writer waiting in down_write()/write_lock() #3
+ *
+ * down_read/read_lock()#3 has the consequence, that rw semaphores and rw
+ * locks on RT are not writer fair, but writers, which should be avoided in
+ * RT tasks (think mmap_sem), are subject to the rtmutex priority/DL
+ * inheritance mechanism.
+ *
+ * It's possible to make the rw primitives writer fair by keeping a list of
+ * active readers. A blocked writer would force all newly incoming readers
+ * to block on the rtmutex, but the rtmutex would have to be proxy locked
+ * for one reader after the other. We can't use multi-reader inheritance
+ * because there is no way to support that with SCHED_DEADLINE.
+ * Implementing the one by one reader boosting/handover mechanism is a
+ * major surgery for a very dubious value.
+ *
+ * The risk of writer starvation is there, but the pathological use cases
+ * which trigger it are not necessarily the typical RT workloads.
+ *
+ * Common code shared between RT rw_semaphore and rwlock
+ */
+
+static __always_inline int rwbase_read_trylock(struct rwbase_rt *rwb)
+{
+ int r;
+
+ /*
+ * Increment reader count, if sem->readers < 0, i.e. READER_BIAS is
+ * set.
+ */
+ for (r = atomic_read(&rwb->readers); r < 0;) {
+ if (likely(atomic_try_cmpxchg(&rwb->readers, &r, r + 1)))
+ return 1;
+ }
+ return 0;
+}
+
+static int __sched __rwbase_read_lock(struct rwbase_rt *rwb,
+ unsigned int state)
+{
+ struct rt_mutex_base *rtm = &rwb->rtmutex;
+ int ret;
+
+ raw_spin_lock_irq(&rtm->wait_lock);
+ /*
+ * Allow readers, as long as the writer has not completely
+ * acquired the semaphore for write.
+ */
+ if (atomic_read(&rwb->readers) != WRITER_BIAS) {
+ atomic_inc(&rwb->readers);
+ raw_spin_unlock_irq(&rtm->wait_lock);
+ return 0;
+ }
+
+ /*
+ * Call into the slow lock path with the rtmutex->wait_lock
+ * held, so this can't result in the following race:
+ *
+ * Reader1 Reader2 Writer
+ * down_read()
+ * down_write()
+ * rtmutex_lock(m)
+ * wait()
+ * down_read()
+ * unlock(m->wait_lock)
+ * up_read()
+ * wake(Writer)
+ * lock(m->wait_lock)
+ * sem->writelocked=true
+ * unlock(m->wait_lock)
+ *
+ * up_write()
+ * sem->writelocked=false
+ * rtmutex_unlock(m)
+ * down_read()
+ * down_write()
+ * rtmutex_lock(m)
+ * wait()
+ * rtmutex_lock(m)
+ *
+ * That would put Reader1 behind the writer waiting on
+ * Reader2 to call up_read(), which might be unbound.
+ */
+
+ /*
+ * For rwlocks this returns 0 unconditionally, so the below
+ * !ret conditionals are optimized out.
+ */
+ ret = rwbase_rtmutex_slowlock_locked(rtm, state);
+
+ /*
+ * On success the rtmutex is held, so there can't be a writer
+ * active. Increment the reader count and immediately drop the
+ * rtmutex again.
+ *
+ * rtmutex->wait_lock has to be unlocked in any case of course.
+ */
+ if (!ret)
+ atomic_inc(&rwb->readers);
+ raw_spin_unlock_irq(&rtm->wait_lock);
+ if (!ret)
+ rwbase_rtmutex_unlock(rtm);
+ return ret;
+}
+
+static __always_inline int rwbase_read_lock(struct rwbase_rt *rwb,
+ unsigned int state)
+{
+ if (rwbase_read_trylock(rwb))
+ return 0;
+
+ return __rwbase_read_lock(rwb, state);
+}
+
+static void __sched __rwbase_read_unlock(struct rwbase_rt *rwb,
+ unsigned int state)
+{
+ struct rt_mutex_base *rtm = &rwb->rtmutex;
+ struct task_struct *owner;
+
+ raw_spin_lock_irq(&rtm->wait_lock);
+ /*
+ * Wake the writer, i.e. the rtmutex owner. It might release the
+ * rtmutex concurrently in the fast path (due to a signal), but to
+ * clean up rwb->readers it needs to acquire rtm->wait_lock. The
+ * worst case which can happen is a spurious wakeup.
+ */
+ owner = rt_mutex_owner(rtm);
+ if (owner)
+ wake_up_state(owner, state);
+
+ raw_spin_unlock_irq(&rtm->wait_lock);
+}
+
+static __always_inline void rwbase_read_unlock(struct rwbase_rt *rwb,
+ unsigned int state)
+{
+ /*
+ * rwb->readers can only hit 0 when a writer is waiting for the
+ * active readers to leave the critical section.
+ */
+ if (unlikely(atomic_dec_and_test(&rwb->readers)))
+ __rwbase_read_unlock(rwb, state);
+}
+
+static inline void __rwbase_write_unlock(struct rwbase_rt *rwb, int bias,
+ unsigned long flags)
+{
+ struct rt_mutex_base *rtm = &rwb->rtmutex;
+
+ atomic_add(READER_BIAS - bias, &rwb->readers);
+ raw_spin_unlock_irqrestore(&rtm->wait_lock, flags);
+ rwbase_rtmutex_unlock(rtm);
+}
+
+static inline void rwbase_write_unlock(struct rwbase_rt *rwb)
+{
+ struct rt_mutex_base *rtm = &rwb->rtmutex;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&rtm->wait_lock, flags);
+ __rwbase_write_unlock(rwb, WRITER_BIAS, flags);
+}
+
+static inline void rwbase_write_downgrade(struct rwbase_rt *rwb)
+{
+ struct rt_mutex_base *rtm = &rwb->rtmutex;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&rtm->wait_lock, flags);
+ /* Release it and account current as reader */
+ __rwbase_write_unlock(rwb, WRITER_BIAS - 1, flags);
+}
+
+static int __sched rwbase_write_lock(struct rwbase_rt *rwb,
+ unsigned int state)
+{
+ struct rt_mutex_base *rtm = &rwb->rtmutex;
+ unsigned long flags;
+
+ /* Take the rtmutex as a first step */
+ if (rwbase_rtmutex_lock_state(rtm, state))
+ return -EINTR;
+
+ /* Force readers into slow path */
+ atomic_sub(READER_BIAS, &rwb->readers);
+
+ raw_spin_lock_irqsave(&rtm->wait_lock, flags);
+ /*
+ * set_current_state() for rw_semaphore
+ * current_save_and_set_rtlock_wait_state() for rwlock
+ */
+ rwbase_set_and_save_current_state(state);
+
+ /* Block until all readers have left the critical section. */
+ for (; atomic_read(&rwb->readers);) {
+ /* Optimized out for rwlocks */
+ if (rwbase_signal_pending_state(state, current)) {
+ __set_current_state(TASK_RUNNING);
+ __rwbase_write_unlock(rwb, 0, flags);
+ return -EINTR;
+ }
+ raw_spin_unlock_irqrestore(&rtm->wait_lock, flags);
+
+ /*
+ * Schedule and wait for the readers to leave the critical
+ * section. The last reader leaving it wakes the waiter.
+ */
+ if (atomic_read(&rwb->readers) != 0)
+ rwbase_schedule();
+ set_current_state(state);
+ raw_spin_lock_irqsave(&rtm->wait_lock, flags);
+ }
+
+ atomic_set(&rwb->readers, WRITER_BIAS);
+ rwbase_restore_current_state();
+ raw_spin_unlock_irqrestore(&rtm->wait_lock, flags);
+ return 0;
+}
+
+static inline int rwbase_write_trylock(struct rwbase_rt *rwb)
+{
+ struct rt_mutex_base *rtm = &rwb->rtmutex;
+ unsigned long flags;
+
+ if (!rwbase_rtmutex_trylock(rtm))
+ return 0;
+
+ atomic_sub(READER_BIAS, &rwb->readers);
+
+ raw_spin_lock_irqsave(&rtm->wait_lock, flags);
+ if (!atomic_read(&rwb->readers)) {
+ atomic_set(&rwb->readers, WRITER_BIAS);
+ raw_spin_unlock_irqrestore(&rtm->wait_lock, flags);
+ return 1;
+ }
+ __rwbase_write_unlock(rwb, 0, flags);
+ return 0;
+}
diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c
index 16bfbb10c74d..9215b4d6a9de 100644
--- a/kernel/locking/rwsem.c
+++ b/kernel/locking/rwsem.c
@@ -28,6 +28,7 @@
#include <linux/rwsem.h>
#include <linux/atomic.h>
+#ifndef CONFIG_PREEMPT_RT
#include "lock_events.h"
/*
@@ -1165,7 +1166,7 @@ out_nolock:
* handle waking up a waiter on the semaphore
* - up_read/up_write has decremented the active part of count if we come here
*/
-static struct rw_semaphore *rwsem_wake(struct rw_semaphore *sem, long count)
+static struct rw_semaphore *rwsem_wake(struct rw_semaphore *sem)
{
unsigned long flags;
DEFINE_WAKE_Q(wake_q);
@@ -1297,7 +1298,7 @@ static inline void __up_read(struct rw_semaphore *sem)
if (unlikely((tmp & (RWSEM_LOCK_MASK|RWSEM_FLAG_WAITERS)) ==
RWSEM_FLAG_WAITERS)) {
clear_nonspinnable(sem);
- rwsem_wake(sem, tmp);
+ rwsem_wake(sem);
}
}
@@ -1319,7 +1320,7 @@ static inline void __up_write(struct rw_semaphore *sem)
rwsem_clear_owner(sem);
tmp = atomic_long_fetch_add_release(-RWSEM_WRITER_LOCKED, &sem->count);
if (unlikely(tmp & RWSEM_FLAG_WAITERS))
- rwsem_wake(sem, tmp);
+ rwsem_wake(sem);
}
/*
@@ -1344,6 +1345,114 @@ static inline void __downgrade_write(struct rw_semaphore *sem)
rwsem_downgrade_wake(sem);
}
+#else /* !CONFIG_PREEMPT_RT */
+
+#define RT_MUTEX_BUILD_MUTEX
+#include "rtmutex.c"
+
+#define rwbase_set_and_save_current_state(state) \
+ set_current_state(state)
+
+#define rwbase_restore_current_state() \
+ __set_current_state(TASK_RUNNING)
+
+#define rwbase_rtmutex_lock_state(rtm, state) \
+ __rt_mutex_lock(rtm, state)
+
+#define rwbase_rtmutex_slowlock_locked(rtm, state) \
+ __rt_mutex_slowlock_locked(rtm, NULL, state)
+
+#define rwbase_rtmutex_unlock(rtm) \
+ __rt_mutex_unlock(rtm)
+
+#define rwbase_rtmutex_trylock(rtm) \
+ __rt_mutex_trylock(rtm)
+
+#define rwbase_signal_pending_state(state, current) \
+ signal_pending_state(state, current)
+
+#define rwbase_schedule() \
+ schedule()
+
+#include "rwbase_rt.c"
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void __rwsem_init(struct rw_semaphore *sem, const char *name,
+ struct lock_class_key *key)
+{
+ debug_check_no_locks_freed((void *)sem, sizeof(*sem));
+ lockdep_init_map_wait(&sem->dep_map, name, key, 0, LD_WAIT_SLEEP);
+}
+EXPORT_SYMBOL(__rwsem_init);
+#endif
+
+static inline void __down_read(struct rw_semaphore *sem)
+{
+ rwbase_read_lock(&sem->rwbase, TASK_UNINTERRUPTIBLE);
+}
+
+static inline int __down_read_interruptible(struct rw_semaphore *sem)
+{
+ return rwbase_read_lock(&sem->rwbase, TASK_INTERRUPTIBLE);
+}
+
+static inline int __down_read_killable(struct rw_semaphore *sem)
+{
+ return rwbase_read_lock(&sem->rwbase, TASK_KILLABLE);
+}
+
+static inline int __down_read_trylock(struct rw_semaphore *sem)
+{
+ return rwbase_read_trylock(&sem->rwbase);
+}
+
+static inline void __up_read(struct rw_semaphore *sem)
+{
+ rwbase_read_unlock(&sem->rwbase, TASK_NORMAL);
+}
+
+static inline void __sched __down_write(struct rw_semaphore *sem)
+{
+ rwbase_write_lock(&sem->rwbase, TASK_UNINTERRUPTIBLE);
+}
+
+static inline int __sched __down_write_killable(struct rw_semaphore *sem)
+{
+ return rwbase_write_lock(&sem->rwbase, TASK_KILLABLE);
+}
+
+static inline int __down_write_trylock(struct rw_semaphore *sem)
+{
+ return rwbase_write_trylock(&sem->rwbase);
+}
+
+static inline void __up_write(struct rw_semaphore *sem)
+{
+ rwbase_write_unlock(&sem->rwbase);
+}
+
+static inline void __downgrade_write(struct rw_semaphore *sem)
+{
+ rwbase_write_downgrade(&sem->rwbase);
+}
+
+/* Debug stubs for the common API */
+#define DEBUG_RWSEMS_WARN_ON(c, sem)
+
+static inline void __rwsem_set_reader_owned(struct rw_semaphore *sem,
+ struct task_struct *owner)
+{
+}
+
+static inline bool is_rwsem_reader_owned(struct rw_semaphore *sem)
+{
+ int count = atomic_read(&sem->rwbase.readers);
+
+ return count < 0 && count != READER_BIAS;
+}
+
+#endif /* CONFIG_PREEMPT_RT */
+
/*
* lock for reading
*/
diff --git a/kernel/locking/semaphore.c b/kernel/locking/semaphore.c
index 9aa855a96c4a..9ee381e4d2a4 100644
--- a/kernel/locking/semaphore.c
+++ b/kernel/locking/semaphore.c
@@ -54,6 +54,7 @@ void down(struct semaphore *sem)
{
unsigned long flags;
+ might_sleep();
raw_spin_lock_irqsave(&sem->lock, flags);
if (likely(sem->count > 0))
sem->count--;
@@ -77,6 +78,7 @@ int down_interruptible(struct semaphore *sem)
unsigned long flags;
int result = 0;
+ might_sleep();
raw_spin_lock_irqsave(&sem->lock, flags);
if (likely(sem->count > 0))
sem->count--;
@@ -103,6 +105,7 @@ int down_killable(struct semaphore *sem)
unsigned long flags;
int result = 0;
+ might_sleep();
raw_spin_lock_irqsave(&sem->lock, flags);
if (likely(sem->count > 0))
sem->count--;
@@ -157,6 +160,7 @@ int down_timeout(struct semaphore *sem, long timeout)
unsigned long flags;
int result = 0;
+ might_sleep();
raw_spin_lock_irqsave(&sem->lock, flags);
if (likely(sem->count > 0))
sem->count--;
diff --git a/kernel/locking/spinlock.c b/kernel/locking/spinlock.c
index c8d7ad9fb9b2..c5830cfa379a 100644
--- a/kernel/locking/spinlock.c
+++ b/kernel/locking/spinlock.c
@@ -124,8 +124,11 @@ void __lockfunc __raw_##op##_lock_bh(locktype##_t *lock) \
* __[spin|read|write]_lock_bh()
*/
BUILD_LOCK_OPS(spin, raw_spinlock);
+
+#ifndef CONFIG_PREEMPT_RT
BUILD_LOCK_OPS(read, rwlock);
BUILD_LOCK_OPS(write, rwlock);
+#endif
#endif
@@ -209,6 +212,8 @@ void __lockfunc _raw_spin_unlock_bh(raw_spinlock_t *lock)
EXPORT_SYMBOL(_raw_spin_unlock_bh);
#endif
+#ifndef CONFIG_PREEMPT_RT
+
#ifndef CONFIG_INLINE_READ_TRYLOCK
int __lockfunc _raw_read_trylock(rwlock_t *lock)
{
@@ -353,6 +358,8 @@ void __lockfunc _raw_write_unlock_bh(rwlock_t *lock)
EXPORT_SYMBOL(_raw_write_unlock_bh);
#endif
+#endif /* !CONFIG_PREEMPT_RT */
+
#ifdef CONFIG_DEBUG_LOCK_ALLOC
void __lockfunc _raw_spin_lock_nested(raw_spinlock_t *lock, int subclass)
diff --git a/kernel/locking/spinlock_debug.c b/kernel/locking/spinlock_debug.c
index b9d93087ee66..14235671a1a7 100644
--- a/kernel/locking/spinlock_debug.c
+++ b/kernel/locking/spinlock_debug.c
@@ -31,6 +31,7 @@ void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name,
EXPORT_SYMBOL(__raw_spin_lock_init);
+#ifndef CONFIG_PREEMPT_RT
void __rwlock_init(rwlock_t *lock, const char *name,
struct lock_class_key *key)
{
@@ -48,6 +49,7 @@ void __rwlock_init(rwlock_t *lock, const char *name,
}
EXPORT_SYMBOL(__rwlock_init);
+#endif
static void spin_dump(raw_spinlock_t *lock, const char *msg)
{
@@ -139,6 +141,7 @@ void do_raw_spin_unlock(raw_spinlock_t *lock)
arch_spin_unlock(&lock->raw_lock);
}
+#ifndef CONFIG_PREEMPT_RT
static void rwlock_bug(rwlock_t *lock, const char *msg)
{
if (!debug_locks_off())
@@ -228,3 +231,5 @@ void do_raw_write_unlock(rwlock_t *lock)
debug_write_unlock(lock);
arch_write_unlock(&lock->raw_lock);
}
+
+#endif /* !CONFIG_PREEMPT_RT */
diff --git a/kernel/locking/spinlock_rt.c b/kernel/locking/spinlock_rt.c
new file mode 100644
index 000000000000..d2912e44d61f
--- /dev/null
+++ b/kernel/locking/spinlock_rt.c
@@ -0,0 +1,263 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PREEMPT_RT substitution for spin/rw_locks
+ *
+ * spinlocks and rwlocks on RT are based on rtmutexes, with a few twists to
+ * resemble the non RT semantics:
+ *
+ * - Contrary to plain rtmutexes, spinlocks and rwlocks are state
+ * preserving. The task state is saved before blocking on the underlying
+ * rtmutex, and restored when the lock has been acquired. Regular wakeups
+ * during that time are redirected to the saved state so no wake up is
+ * missed.
+ *
+ * - Non RT spin/rwlocks disable preemption and eventually interrupts.
+ * Disabling preemption has the side effect of disabling migration and
+ * preventing RCU grace periods.
+ *
+ * The RT substitutions explicitly disable migration and take
+ * rcu_read_lock() across the lock held section.
+ */
+#include <linux/spinlock.h>
+#include <linux/export.h>
+
+#define RT_MUTEX_BUILD_SPINLOCKS
+#include "rtmutex.c"
+
+static __always_inline void rtlock_lock(struct rt_mutex_base *rtm)
+{
+ if (unlikely(!rt_mutex_cmpxchg_acquire(rtm, NULL, current)))
+ rtlock_slowlock(rtm);
+}
+
+static __always_inline void __rt_spin_lock(spinlock_t *lock)
+{
+ ___might_sleep(__FILE__, __LINE__, 0);
+ rtlock_lock(&lock->lock);
+ rcu_read_lock();
+ migrate_disable();
+}
+
+void __sched rt_spin_lock(spinlock_t *lock)
+{
+ spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);
+ __rt_spin_lock(lock);
+}
+EXPORT_SYMBOL(rt_spin_lock);
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void __sched rt_spin_lock_nested(spinlock_t *lock, int subclass)
+{
+ spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
+ __rt_spin_lock(lock);
+}
+EXPORT_SYMBOL(rt_spin_lock_nested);
+
+void __sched rt_spin_lock_nest_lock(spinlock_t *lock,
+ struct lockdep_map *nest_lock)
+{
+ spin_acquire_nest(&lock->dep_map, 0, 0, nest_lock, _RET_IP_);
+ __rt_spin_lock(lock);
+}
+EXPORT_SYMBOL(rt_spin_lock_nest_lock);
+#endif
+
+void __sched rt_spin_unlock(spinlock_t *lock)
+{
+ spin_release(&lock->dep_map, _RET_IP_);
+ migrate_enable();
+ rcu_read_unlock();
+
+ if (unlikely(!rt_mutex_cmpxchg_release(&lock->lock, current, NULL)))
+ rt_mutex_slowunlock(&lock->lock);
+}
+EXPORT_SYMBOL(rt_spin_unlock);
+
+/*
+ * Wait for the lock to get unlocked: instead of polling for an unlock
+ * (like raw spinlocks do), lock and unlock, to force the kernel to
+ * schedule if there's contention:
+ */
+void __sched rt_spin_lock_unlock(spinlock_t *lock)
+{
+ spin_lock(lock);
+ spin_unlock(lock);
+}
+EXPORT_SYMBOL(rt_spin_lock_unlock);
+
+static __always_inline int __rt_spin_trylock(spinlock_t *lock)
+{
+ int ret = 1;
+
+ if (unlikely(!rt_mutex_cmpxchg_acquire(&lock->lock, NULL, current)))
+ ret = rt_mutex_slowtrylock(&lock->lock);
+
+ if (ret) {
+ spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);
+ rcu_read_lock();
+ migrate_disable();
+ }
+ return ret;
+}
+
+int __sched rt_spin_trylock(spinlock_t *lock)
+{
+ return __rt_spin_trylock(lock);
+}
+EXPORT_SYMBOL(rt_spin_trylock);
+
+int __sched rt_spin_trylock_bh(spinlock_t *lock)
+{
+ int ret;
+
+ local_bh_disable();
+ ret = __rt_spin_trylock(lock);
+ if (!ret)
+ local_bh_enable();
+ return ret;
+}
+EXPORT_SYMBOL(rt_spin_trylock_bh);
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void __rt_spin_lock_init(spinlock_t *lock, const char *name,
+ struct lock_class_key *key, bool percpu)
+{
+ u8 type = percpu ? LD_LOCK_PERCPU : LD_LOCK_NORMAL;
+
+ debug_check_no_locks_freed((void *)lock, sizeof(*lock));
+ lockdep_init_map_type(&lock->dep_map, name, key, 0, LD_WAIT_CONFIG,
+ LD_WAIT_INV, type);
+}
+EXPORT_SYMBOL(__rt_spin_lock_init);
+#endif
+
+/*
+ * RT-specific reader/writer locks
+ */
+#define rwbase_set_and_save_current_state(state) \
+ current_save_and_set_rtlock_wait_state()
+
+#define rwbase_restore_current_state() \
+ current_restore_rtlock_saved_state()
+
+static __always_inline int
+rwbase_rtmutex_lock_state(struct rt_mutex_base *rtm, unsigned int state)
+{
+ if (unlikely(!rt_mutex_cmpxchg_acquire(rtm, NULL, current)))
+ rtlock_slowlock(rtm);
+ return 0;
+}
+
+static __always_inline int
+rwbase_rtmutex_slowlock_locked(struct rt_mutex_base *rtm, unsigned int state)
+{
+ rtlock_slowlock_locked(rtm);
+ return 0;
+}
+
+static __always_inline void rwbase_rtmutex_unlock(struct rt_mutex_base *rtm)
+{
+ if (likely(rt_mutex_cmpxchg_acquire(rtm, current, NULL)))
+ return;
+
+ rt_mutex_slowunlock(rtm);
+}
+
+static __always_inline int rwbase_rtmutex_trylock(struct rt_mutex_base *rtm)
+{
+ if (likely(rt_mutex_cmpxchg_acquire(rtm, NULL, current)))
+ return 1;
+
+ return rt_mutex_slowtrylock(rtm);
+}
+
+#define rwbase_signal_pending_state(state, current) (0)
+
+#define rwbase_schedule() \
+ schedule_rtlock()
+
+#include "rwbase_rt.c"
+/*
+ * The common functions which get wrapped into the rwlock API.
+ */
+int __sched rt_read_trylock(rwlock_t *rwlock)
+{
+ int ret;
+
+ ret = rwbase_read_trylock(&rwlock->rwbase);
+ if (ret) {
+ rwlock_acquire_read(&rwlock->dep_map, 0, 1, _RET_IP_);
+ rcu_read_lock();
+ migrate_disable();
+ }
+ return ret;
+}
+EXPORT_SYMBOL(rt_read_trylock);
+
+int __sched rt_write_trylock(rwlock_t *rwlock)
+{
+ int ret;
+
+ ret = rwbase_write_trylock(&rwlock->rwbase);
+ if (ret) {
+ rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_);
+ rcu_read_lock();
+ migrate_disable();
+ }
+ return ret;
+}
+EXPORT_SYMBOL(rt_write_trylock);
+
+void __sched rt_read_lock(rwlock_t *rwlock)
+{
+ ___might_sleep(__FILE__, __LINE__, 0);
+ rwlock_acquire_read(&rwlock->dep_map, 0, 0, _RET_IP_);
+ rwbase_read_lock(&rwlock->rwbase, TASK_RTLOCK_WAIT);
+ rcu_read_lock();
+ migrate_disable();
+}
+EXPORT_SYMBOL(rt_read_lock);
+
+void __sched rt_write_lock(rwlock_t *rwlock)
+{
+ ___might_sleep(__FILE__, __LINE__, 0);
+ rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_);
+ rwbase_write_lock(&rwlock->rwbase, TASK_RTLOCK_WAIT);
+ rcu_read_lock();
+ migrate_disable();
+}
+EXPORT_SYMBOL(rt_write_lock);
+
+void __sched rt_read_unlock(rwlock_t *rwlock)
+{
+ rwlock_release(&rwlock->dep_map, _RET_IP_);
+ migrate_enable();
+ rcu_read_unlock();
+ rwbase_read_unlock(&rwlock->rwbase, TASK_RTLOCK_WAIT);
+}
+EXPORT_SYMBOL(rt_read_unlock);
+
+void __sched rt_write_unlock(rwlock_t *rwlock)
+{
+ rwlock_release(&rwlock->dep_map, _RET_IP_);
+ rcu_read_unlock();
+ migrate_enable();
+ rwbase_write_unlock(&rwlock->rwbase);
+}
+EXPORT_SYMBOL(rt_write_unlock);
+
+int __sched rt_rwlock_is_contended(rwlock_t *rwlock)
+{
+ return rw_base_is_contended(&rwlock->rwbase);
+}
+EXPORT_SYMBOL(rt_rwlock_is_contended);
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+void __rt_rwlock_init(rwlock_t *rwlock, const char *name,
+ struct lock_class_key *key)
+{
+ debug_check_no_locks_freed((void *)rwlock, sizeof(*rwlock));
+ lockdep_init_map_wait(&rwlock->dep_map, name, key, 0, LD_WAIT_CONFIG);
+}
+EXPORT_SYMBOL(__rt_rwlock_init);
+#endif
diff --git a/kernel/locking/ww_mutex.h b/kernel/locking/ww_mutex.h
new file mode 100644
index 000000000000..56f139201f24
--- /dev/null
+++ b/kernel/locking/ww_mutex.h
@@ -0,0 +1,569 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef WW_RT
+
+#define MUTEX mutex
+#define MUTEX_WAITER mutex_waiter
+
+static inline struct mutex_waiter *
+__ww_waiter_first(struct mutex *lock)
+{
+ struct mutex_waiter *w;
+
+ w = list_first_entry(&lock->wait_list, struct mutex_waiter, list);
+ if (list_entry_is_head(w, &lock->wait_list, list))
+ return NULL;
+
+ return w;
+}
+
+static inline struct mutex_waiter *
+__ww_waiter_next(struct mutex *lock, struct mutex_waiter *w)
+{
+ w = list_next_entry(w, list);
+ if (list_entry_is_head(w, &lock->wait_list, list))
+ return NULL;
+
+ return w;
+}
+
+static inline struct mutex_waiter *
+__ww_waiter_prev(struct mutex *lock, struct mutex_waiter *w)
+{
+ w = list_prev_entry(w, list);
+ if (list_entry_is_head(w, &lock->wait_list, list))
+ return NULL;
+
+ return w;
+}
+
+static inline struct mutex_waiter *
+__ww_waiter_last(struct mutex *lock)
+{
+ struct mutex_waiter *w;
+
+ w = list_last_entry(&lock->wait_list, struct mutex_waiter, list);
+ if (list_entry_is_head(w, &lock->wait_list, list))
+ return NULL;
+
+ return w;
+}
+
+static inline void
+__ww_waiter_add(struct mutex *lock, struct mutex_waiter *waiter, struct mutex_waiter *pos)
+{
+ struct list_head *p = &lock->wait_list;
+ if (pos)
+ p = &pos->list;
+ __mutex_add_waiter(lock, waiter, p);
+}
+
+static inline struct task_struct *
+__ww_mutex_owner(struct mutex *lock)
+{
+ return __mutex_owner(lock);
+}
+
+static inline bool
+__ww_mutex_has_waiters(struct mutex *lock)
+{
+ return atomic_long_read(&lock->owner) & MUTEX_FLAG_WAITERS;
+}
+
+static inline void lock_wait_lock(struct mutex *lock)
+{
+ raw_spin_lock(&lock->wait_lock);
+}
+
+static inline void unlock_wait_lock(struct mutex *lock)
+{
+ raw_spin_unlock(&lock->wait_lock);
+}
+
+static inline void lockdep_assert_wait_lock_held(struct mutex *lock)
+{
+ lockdep_assert_held(&lock->wait_lock);
+}
+
+#else /* WW_RT */
+
+#define MUTEX rt_mutex
+#define MUTEX_WAITER rt_mutex_waiter
+
+static inline struct rt_mutex_waiter *
+__ww_waiter_first(struct rt_mutex *lock)
+{
+ struct rb_node *n = rb_first(&lock->rtmutex.waiters.rb_root);
+ if (!n)
+ return NULL;
+ return rb_entry(n, struct rt_mutex_waiter, tree_entry);
+}
+
+static inline struct rt_mutex_waiter *
+__ww_waiter_next(struct rt_mutex *lock, struct rt_mutex_waiter *w)
+{
+ struct rb_node *n = rb_next(&w->tree_entry);
+ if (!n)
+ return NULL;
+ return rb_entry(n, struct rt_mutex_waiter, tree_entry);
+}
+
+static inline struct rt_mutex_waiter *
+__ww_waiter_prev(struct rt_mutex *lock, struct rt_mutex_waiter *w)
+{
+ struct rb_node *n = rb_prev(&w->tree_entry);
+ if (!n)
+ return NULL;
+ return rb_entry(n, struct rt_mutex_waiter, tree_entry);
+}
+
+static inline struct rt_mutex_waiter *
+__ww_waiter_last(struct rt_mutex *lock)
+{
+ struct rb_node *n = rb_last(&lock->rtmutex.waiters.rb_root);
+ if (!n)
+ return NULL;
+ return rb_entry(n, struct rt_mutex_waiter, tree_entry);
+}
+
+static inline void
+__ww_waiter_add(struct rt_mutex *lock, struct rt_mutex_waiter *waiter, struct rt_mutex_waiter *pos)
+{
+ /* RT unconditionally adds the waiter first and then removes it on error */
+}
+
+static inline struct task_struct *
+__ww_mutex_owner(struct rt_mutex *lock)
+{
+ return rt_mutex_owner(&lock->rtmutex);
+}
+
+static inline bool
+__ww_mutex_has_waiters(struct rt_mutex *lock)
+{
+ return rt_mutex_has_waiters(&lock->rtmutex);
+}
+
+static inline void lock_wait_lock(struct rt_mutex *lock)
+{
+ raw_spin_lock(&lock->rtmutex.wait_lock);
+}
+
+static inline void unlock_wait_lock(struct rt_mutex *lock)
+{
+ raw_spin_unlock(&lock->rtmutex.wait_lock);
+}
+
+static inline void lockdep_assert_wait_lock_held(struct rt_mutex *lock)
+{
+ lockdep_assert_held(&lock->rtmutex.wait_lock);
+}
+
+#endif /* WW_RT */
+
+/*
+ * Wait-Die:
+ * The newer transactions are killed when:
+ * It (the new transaction) makes a request for a lock being held
+ * by an older transaction.
+ *
+ * Wound-Wait:
+ * The newer transactions are wounded when:
+ * An older transaction makes a request for a lock being held by
+ * the newer transaction.
+ */
+
+/*
+ * Associate the ww_mutex @ww with the context @ww_ctx under which we acquired
+ * it.
+ */
+static __always_inline void
+ww_mutex_lock_acquired(struct ww_mutex *ww, struct ww_acquire_ctx *ww_ctx)
+{
+#ifdef DEBUG_WW_MUTEXES
+ /*
+ * If this WARN_ON triggers, you used ww_mutex_lock to acquire,
+ * but released with a normal mutex_unlock in this call.
+ *
+ * This should never happen, always use ww_mutex_unlock.
+ */
+ DEBUG_LOCKS_WARN_ON(ww->ctx);
+
+ /*
+ * Not quite done after calling ww_acquire_done() ?
+ */
+ DEBUG_LOCKS_WARN_ON(ww_ctx->done_acquire);
+
+ if (ww_ctx->contending_lock) {
+ /*
+ * After -EDEADLK you tried to
+ * acquire a different ww_mutex? Bad!
+ */
+ DEBUG_LOCKS_WARN_ON(ww_ctx->contending_lock != ww);
+
+ /*
+ * You called ww_mutex_lock after receiving -EDEADLK,
+ * but 'forgot' to unlock everything else first?
+ */
+ DEBUG_LOCKS_WARN_ON(ww_ctx->acquired > 0);
+ ww_ctx->contending_lock = NULL;
+ }
+
+ /*
+ * Naughty, using a different class will lead to undefined behavior!
+ */
+ DEBUG_LOCKS_WARN_ON(ww_ctx->ww_class != ww->ww_class);
+#endif
+ ww_ctx->acquired++;
+ ww->ctx = ww_ctx;
+}
+
+/*
+ * Determine if @a is 'less' than @b. IOW, either @a is a lower priority task
+ * or, when of equal priority, a younger transaction than @b.
+ *
+ * Depending on the algorithm, @a will either need to wait for @b, or die.
+ */
+static inline bool
+__ww_ctx_less(struct ww_acquire_ctx *a, struct ww_acquire_ctx *b)
+{
+/*
+ * Can only do the RT prio for WW_RT, because task->prio isn't stable due to PI,
+ * so the wait_list ordering will go wobbly. rt_mutex re-queues the waiter and
+ * isn't affected by this.
+ */
+#ifdef WW_RT
+ /* kernel prio; less is more */
+ int a_prio = a->task->prio;
+ int b_prio = b->task->prio;
+
+ if (rt_prio(a_prio) || rt_prio(b_prio)) {
+
+ if (a_prio > b_prio)
+ return true;
+
+ if (a_prio < b_prio)
+ return false;
+
+ /* equal static prio */
+
+ if (dl_prio(a_prio)) {
+ if (dl_time_before(b->task->dl.deadline,
+ a->task->dl.deadline))
+ return true;
+
+ if (dl_time_before(a->task->dl.deadline,
+ b->task->dl.deadline))
+ return false;
+ }
+
+ /* equal prio */
+ }
+#endif
+
+ /* FIFO order tie break -- bigger is younger */
+ return (signed long)(a->stamp - b->stamp) > 0;
+}
+
+/*
+ * Wait-Die; wake a lesser waiter context (when locks held) such that it can
+ * die.
+ *
+ * Among waiters with context, only the first one can have other locks acquired
+ * already (ctx->acquired > 0), because __ww_mutex_add_waiter() and
+ * __ww_mutex_check_kill() wake any but the earliest context.
+ */
+static bool
+__ww_mutex_die(struct MUTEX *lock, struct MUTEX_WAITER *waiter,
+ struct ww_acquire_ctx *ww_ctx)
+{
+ if (!ww_ctx->is_wait_die)
+ return false;
+
+ if (waiter->ww_ctx->acquired > 0 && __ww_ctx_less(waiter->ww_ctx, ww_ctx)) {
+#ifndef WW_RT
+ debug_mutex_wake_waiter(lock, waiter);
+#endif
+ wake_up_process(waiter->task);
+ }
+
+ return true;
+}
+
+/*
+ * Wound-Wait; wound a lesser @hold_ctx if it holds the lock.
+ *
+ * Wound the lock holder if there are waiters with more important transactions
+ * than the lock holders. Even if multiple waiters may wound the lock holder,
+ * it's sufficient that only one does.
+ */
+static bool __ww_mutex_wound(struct MUTEX *lock,
+ struct ww_acquire_ctx *ww_ctx,
+ struct ww_acquire_ctx *hold_ctx)
+{
+ struct task_struct *owner = __ww_mutex_owner(lock);
+
+ lockdep_assert_wait_lock_held(lock);
+
+ /*
+ * Possible through __ww_mutex_add_waiter() when we race with
+ * ww_mutex_set_context_fastpath(). In that case we'll get here again
+ * through __ww_mutex_check_waiters().
+ */
+ if (!hold_ctx)
+ return false;
+
+ /*
+ * Can have !owner because of __mutex_unlock_slowpath(), but if owner,
+ * it cannot go away because we'll have FLAG_WAITERS set and hold
+ * wait_lock.
+ */
+ if (!owner)
+ return false;
+
+ if (ww_ctx->acquired > 0 && __ww_ctx_less(hold_ctx, ww_ctx)) {
+ hold_ctx->wounded = 1;
+
+ /*
+ * wake_up_process() paired with set_current_state()
+ * inserts sufficient barriers to make sure @owner either sees
+ * it's wounded in __ww_mutex_check_kill() or has a
+ * wakeup pending to re-read the wounded state.
+ */
+ if (owner != current)
+ wake_up_process(owner);
+
+ return true;
+ }
+
+ return false;
+}
+
+/*
+ * We just acquired @lock under @ww_ctx, if there are more important contexts
+ * waiting behind us on the wait-list, check if they need to die, or wound us.
+ *
+ * See __ww_mutex_add_waiter() for the list-order construction; basically the
+ * list is ordered by stamp, smallest (oldest) first.
+ *
+ * This relies on never mixing wait-die/wound-wait on the same wait-list;
+ * which is currently ensured by that being a ww_class property.
+ *
+ * The current task must not be on the wait list.
+ */
+static void
+__ww_mutex_check_waiters(struct MUTEX *lock, struct ww_acquire_ctx *ww_ctx)
+{
+ struct MUTEX_WAITER *cur;
+
+ lockdep_assert_wait_lock_held(lock);
+
+ for (cur = __ww_waiter_first(lock); cur;
+ cur = __ww_waiter_next(lock, cur)) {
+
+ if (!cur->ww_ctx)
+ continue;
+
+ if (__ww_mutex_die(lock, cur, ww_ctx) ||
+ __ww_mutex_wound(lock, cur->ww_ctx, ww_ctx))
+ break;
+ }
+}
+
+/*
+ * After acquiring lock with fastpath, where we do not hold wait_lock, set ctx
+ * and wake up any waiters so they can recheck.
+ */
+static __always_inline void
+ww_mutex_set_context_fastpath(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+ ww_mutex_lock_acquired(lock, ctx);
+
+ /*
+ * The lock->ctx update should be visible on all cores before
+ * the WAITERS check is done, otherwise contended waiters might be
+ * missed. The contended waiters will either see ww_ctx == NULL
+ * and keep spinning, or it will acquire wait_lock, add itself
+ * to waiter list and sleep.
+ */
+ smp_mb(); /* See comments above and below. */
+
+ /*
+ * [W] ww->ctx = ctx [W] MUTEX_FLAG_WAITERS
+ * MB MB
+ * [R] MUTEX_FLAG_WAITERS [R] ww->ctx
+ *
+ * The memory barrier above pairs with the memory barrier in
+ * __ww_mutex_add_waiter() and makes sure we either observe ww->ctx
+ * and/or !empty list.
+ */
+ if (likely(!__ww_mutex_has_waiters(&lock->base)))
+ return;
+
+ /*
+ * Uh oh, we raced in fastpath, check if any of the waiters need to
+ * die or wound us.
+ */
+ lock_wait_lock(&lock->base);
+ __ww_mutex_check_waiters(&lock->base, ctx);
+ unlock_wait_lock(&lock->base);
+}
+
+static __always_inline int
+__ww_mutex_kill(struct MUTEX *lock, struct ww_acquire_ctx *ww_ctx)
+{
+ if (ww_ctx->acquired > 0) {
+#ifdef DEBUG_WW_MUTEXES
+ struct ww_mutex *ww;
+
+ ww = container_of(lock, struct ww_mutex, base);
+ DEBUG_LOCKS_WARN_ON(ww_ctx->contending_lock);
+ ww_ctx->contending_lock = ww;
+#endif
+ return -EDEADLK;
+ }
+
+ return 0;
+}
+
+/*
+ * Check the wound condition for the current lock acquire.
+ *
+ * Wound-Wait: If we're wounded, kill ourself.
+ *
+ * Wait-Die: If we're trying to acquire a lock already held by an older
+ * context, kill ourselves.
+ *
+ * Since __ww_mutex_add_waiter() orders the wait-list on stamp, we only have to
+ * look at waiters before us in the wait-list.
+ */
+static inline int
+__ww_mutex_check_kill(struct MUTEX *lock, struct MUTEX_WAITER *waiter,
+ struct ww_acquire_ctx *ctx)
+{
+ struct ww_mutex *ww = container_of(lock, struct ww_mutex, base);
+ struct ww_acquire_ctx *hold_ctx = READ_ONCE(ww->ctx);
+ struct MUTEX_WAITER *cur;
+
+ if (ctx->acquired == 0)
+ return 0;
+
+ if (!ctx->is_wait_die) {
+ if (ctx->wounded)
+ return __ww_mutex_kill(lock, ctx);
+
+ return 0;
+ }
+
+ if (hold_ctx && __ww_ctx_less(ctx, hold_ctx))
+ return __ww_mutex_kill(lock, ctx);
+
+ /*
+ * If there is a waiter in front of us that has a context, then its
+ * stamp is earlier than ours and we must kill ourself.
+ */
+ for (cur = __ww_waiter_prev(lock, waiter); cur;
+ cur = __ww_waiter_prev(lock, cur)) {
+
+ if (!cur->ww_ctx)
+ continue;
+
+ return __ww_mutex_kill(lock, ctx);
+ }
+
+ return 0;
+}
+
+/*
+ * Add @waiter to the wait-list, keep the wait-list ordered by stamp, smallest
+ * first. Such that older contexts are preferred to acquire the lock over
+ * younger contexts.
+ *
+ * Waiters without context are interspersed in FIFO order.
+ *
+ * Furthermore, for Wait-Die kill ourself immediately when possible (there are
+ * older contexts already waiting) to avoid unnecessary waiting and for
+ * Wound-Wait ensure we wound the owning context when it is younger.
+ */
+static inline int
+__ww_mutex_add_waiter(struct MUTEX_WAITER *waiter,
+ struct MUTEX *lock,
+ struct ww_acquire_ctx *ww_ctx)
+{
+ struct MUTEX_WAITER *cur, *pos = NULL;
+ bool is_wait_die;
+
+ if (!ww_ctx) {
+ __ww_waiter_add(lock, waiter, NULL);
+ return 0;
+ }
+
+ is_wait_die = ww_ctx->is_wait_die;
+
+ /*
+ * Add the waiter before the first waiter with a higher stamp.
+ * Waiters without a context are skipped to avoid starving
+ * them. Wait-Die waiters may die here. Wound-Wait waiters
+ * never die here, but they are sorted in stamp order and
+ * may wound the lock holder.
+ */
+ for (cur = __ww_waiter_last(lock); cur;
+ cur = __ww_waiter_prev(lock, cur)) {
+
+ if (!cur->ww_ctx)
+ continue;
+
+ if (__ww_ctx_less(ww_ctx, cur->ww_ctx)) {
+ /*
+ * Wait-Die: if we find an older context waiting, there
+ * is no point in queueing behind it, as we'd have to
+ * die the moment it would acquire the lock.
+ */
+ if (is_wait_die) {
+ int ret = __ww_mutex_kill(lock, ww_ctx);
+
+ if (ret)
+ return ret;
+ }
+
+ break;
+ }
+
+ pos = cur;
+
+ /* Wait-Die: ensure younger waiters die. */
+ __ww_mutex_die(lock, cur, ww_ctx);
+ }
+
+ __ww_waiter_add(lock, waiter, pos);
+
+ /*
+ * Wound-Wait: if we're blocking on a mutex owned by a younger context,
+ * wound that such that we might proceed.
+ */
+ if (!is_wait_die) {
+ struct ww_mutex *ww = container_of(lock, struct ww_mutex, base);
+
+ /*
+ * See ww_mutex_set_context_fastpath(). Orders setting
+ * MUTEX_FLAG_WAITERS vs the ww->ctx load,
+ * such that either we or the fastpath will wound @ww->ctx.
+ */
+ smp_mb();
+ __ww_mutex_wound(lock, ww_ctx, ww->ctx);
+ }
+
+ return 0;
+}
+
+static inline void __ww_mutex_unlock(struct ww_mutex *lock)
+{
+ if (lock->ctx) {
+#ifdef DEBUG_WW_MUTEXES
+ DEBUG_LOCKS_WARN_ON(!lock->ctx->acquired);
+#endif
+ if (lock->ctx->acquired > 0)
+ lock->ctx->acquired--;
+ lock->ctx = NULL;
+ }
+}
diff --git a/kernel/locking/ww_rt_mutex.c b/kernel/locking/ww_rt_mutex.c
new file mode 100644
index 000000000000..3f1fff7d2780
--- /dev/null
+++ b/kernel/locking/ww_rt_mutex.c
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * rtmutex API
+ */
+#include <linux/spinlock.h>
+#include <linux/export.h>
+
+#define RT_MUTEX_BUILD_MUTEX
+#define WW_RT
+#include "rtmutex.c"
+
+static int __sched
+__ww_rt_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx,
+ unsigned int state, unsigned long ip)
+{
+ struct lockdep_map __maybe_unused *nest_lock = NULL;
+ struct rt_mutex *rtm = &lock->base;
+ int ret;
+
+ might_sleep();
+
+ if (ww_ctx) {
+ if (unlikely(ww_ctx == READ_ONCE(lock->ctx)))
+ return -EALREADY;
+
+ /*
+ * Reset the wounded flag after a kill. No other process can
+ * race and wound us here, since they can't have a valid owner
+ * pointer if we don't have any locks held.
+ */
+ if (ww_ctx->acquired == 0)
+ ww_ctx->wounded = 0;
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ nest_lock = &ww_ctx->dep_map;
+#endif
+ }
+ mutex_acquire_nest(&rtm->dep_map, 0, 0, nest_lock, ip);
+
+ if (likely(rt_mutex_cmpxchg_acquire(&rtm->rtmutex, NULL, current))) {
+ if (ww_ctx)
+ ww_mutex_set_context_fastpath(lock, ww_ctx);
+ return 0;
+ }
+
+ ret = rt_mutex_slowlock(&rtm->rtmutex, ww_ctx, state);
+
+ if (ret)
+ mutex_release(&rtm->dep_map, ip);
+ return ret;
+}
+
+int __sched
+ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+ return __ww_rt_mutex_lock(lock, ctx, TASK_UNINTERRUPTIBLE, _RET_IP_);
+}
+EXPORT_SYMBOL(ww_mutex_lock);
+
+int __sched
+ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
+{
+ return __ww_rt_mutex_lock(lock, ctx, TASK_INTERRUPTIBLE, _RET_IP_);
+}
+EXPORT_SYMBOL(ww_mutex_lock_interruptible);
+
+void __sched ww_mutex_unlock(struct ww_mutex *lock)
+{
+ struct rt_mutex *rtm = &lock->base;
+
+ __ww_mutex_unlock(lock);
+
+ mutex_release(&rtm->dep_map, _RET_IP_);
+ __rt_mutex_unlock(&rtm->rtmutex);
+}
+EXPORT_SYMBOL(ww_mutex_unlock);
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 7a4876a3a882..d070059163d7 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -529,7 +529,7 @@ rcu_preempt_deferred_qs_irqrestore(struct task_struct *t, unsigned long flags)
WRITE_ONCE(rnp->exp_tasks, np);
if (IS_ENABLED(CONFIG_RCU_BOOST)) {
/* Snapshot ->boost_mtx ownership w/rnp->lock held. */
- drop_boost_mutex = rt_mutex_owner(&rnp->boost_mtx) == t;
+ drop_boost_mutex = rt_mutex_owner(&rnp->boost_mtx.rtmutex) == t;
if (&t->rcu_node_entry == rnp->boost_tasks)
WRITE_ONCE(rnp->boost_tasks, np);
}
@@ -556,7 +556,7 @@ rcu_preempt_deferred_qs_irqrestore(struct task_struct *t, unsigned long flags)
/* Unboost if we were boosted. */
if (IS_ENABLED(CONFIG_RCU_BOOST) && drop_boost_mutex)
- rt_mutex_futex_unlock(&rnp->boost_mtx);
+ rt_mutex_futex_unlock(&rnp->boost_mtx.rtmutex);
/*
* If this was the last task on the expedited lists,
@@ -1053,7 +1053,7 @@ static int rcu_boost(struct rcu_node *rnp)
* section.
*/
t = container_of(tb, struct task_struct, rcu_node_entry);
- rt_mutex_init_proxy_locked(&rnp->boost_mtx, t);
+ rt_mutex_init_proxy_locked(&rnp->boost_mtx.rtmutex, t);
raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
/* Lock only for side effect: boosts task t's priority. */
rt_mutex_lock(&rnp->boost_mtx);
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 37bec9b05e31..c4462c454ab9 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3776,6 +3776,55 @@ static void ttwu_queue(struct task_struct *p, int cpu, int wake_flags)
}
/*
+ * Invoked from try_to_wake_up() to check whether the task can be woken up.
+ *
+ * The caller holds p::pi_lock if p != current or has preemption
+ * disabled when p == current.
+ *
+ * The rules of PREEMPT_RT saved_state:
+ *
+ * The related locking code always holds p::pi_lock when updating
+ * p::saved_state, which means the code is fully serialized in both cases.
+ *
+ * The lock wait and lock wakeups happen via TASK_RTLOCK_WAIT. No other
+ * bits set. This allows to distinguish all wakeup scenarios.
+ */
+static __always_inline
+bool ttwu_state_match(struct task_struct *p, unsigned int state, int *success)
+{
+ if (IS_ENABLED(CONFIG_DEBUG_PREEMPT)) {
+ WARN_ON_ONCE((state & TASK_RTLOCK_WAIT) &&
+ state != TASK_RTLOCK_WAIT);
+ }
+
+ if (READ_ONCE(p->__state) & state) {
+ *success = 1;
+ return true;
+ }
+
+#ifdef CONFIG_PREEMPT_RT
+ /*
+ * Saved state preserves the task state across blocking on
+ * an RT lock. If the state matches, set p::saved_state to
+ * TASK_RUNNING, but do not wake the task because it waits
+ * for a lock wakeup. Also indicate success because from
+ * the regular waker's point of view this has succeeded.
+ *
+ * After acquiring the lock the task will restore p::__state
+ * from p::saved_state which ensures that the regular
+ * wakeup is not lost. The restore will also set
+ * p::saved_state to TASK_RUNNING so any further tests will
+ * not result in false positives vs. @success
+ */
+ if (p->saved_state & state) {
+ p->saved_state = TASK_RUNNING;
+ *success = 1;
+ }
+#endif
+ return false;
+}
+
+/*
* Notes on Program-Order guarantees on SMP systems.
*
* MIGRATION
@@ -3914,10 +3963,9 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
* - we're serialized against set_special_state() by virtue of
* it disabling IRQs (this allows not taking ->pi_lock).
*/
- if (!(READ_ONCE(p->__state) & state))
+ if (!ttwu_state_match(p, state, &success))
goto out;
- success = 1;
trace_sched_waking(p);
WRITE_ONCE(p->__state, TASK_RUNNING);
trace_sched_wakeup(p);
@@ -3932,14 +3980,11 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
*/
raw_spin_lock_irqsave(&p->pi_lock, flags);
smp_mb__after_spinlock();
- if (!(READ_ONCE(p->__state) & state))
+ if (!ttwu_state_match(p, state, &success))
goto unlock;
trace_sched_waking(p);
- /* We're going to change ->state: */
- success = 1;
-
/*
* Ensure we load p->on_rq _after_ p->state, otherwise it would
* be possible to, falsely, observe p->on_rq == 0 and get stuck
@@ -6061,6 +6106,24 @@ pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
#endif /* CONFIG_SCHED_CORE */
/*
+ * Constants for the sched_mode argument of __schedule().
+ *
+ * The mode argument allows RT enabled kernels to differentiate a
+ * preemption from blocking on an 'sleeping' spin/rwlock. Note that
+ * SM_MASK_PREEMPT for !RT has all bits set, which allows the compiler to
+ * optimize the AND operation out and just check for zero.
+ */
+#define SM_NONE 0x0
+#define SM_PREEMPT 0x1
+#define SM_RTLOCK_WAIT 0x2
+
+#ifndef CONFIG_PREEMPT_RT
+# define SM_MASK_PREEMPT (~0U)
+#else
+# define SM_MASK_PREEMPT SM_PREEMPT
+#endif
+
+/*
* __schedule() is the main scheduler function.
*
* The main means of driving the scheduler and thus entering this function are:
@@ -6099,7 +6162,7 @@ pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
*
* WARNING: must be called with preemption disabled!
*/
-static void __sched notrace __schedule(bool preempt)
+static void __sched notrace __schedule(unsigned int sched_mode)
{
struct task_struct *prev, *next;
unsigned long *switch_count;
@@ -6112,13 +6175,13 @@ static void __sched notrace __schedule(bool preempt)
rq = cpu_rq(cpu);
prev = rq->curr;
- schedule_debug(prev, preempt);
+ schedule_debug(prev, !!sched_mode);
if (sched_feat(HRTICK) || sched_feat(HRTICK_DL))
hrtick_clear(rq);
local_irq_disable();
- rcu_note_context_switch(preempt);
+ rcu_note_context_switch(!!sched_mode);
/*
* Make sure that signal_pending_state()->signal_pending() below
@@ -6152,7 +6215,7 @@ static void __sched notrace __schedule(bool preempt)
* - ptrace_{,un}freeze_traced() can change ->state underneath us.
*/
prev_state = READ_ONCE(prev->__state);
- if (!preempt && prev_state) {
+ if (!(sched_mode & SM_MASK_PREEMPT) && prev_state) {
if (signal_pending_state(prev_state, prev)) {
WRITE_ONCE(prev->__state, TASK_RUNNING);
} else {
@@ -6218,7 +6281,7 @@ static void __sched notrace __schedule(bool preempt)
migrate_disable_switch(rq, prev);
psi_sched_switch(prev, next, !task_on_rq_queued(prev));
- trace_sched_switch(preempt, prev, next);
+ trace_sched_switch(sched_mode & SM_MASK_PREEMPT, prev, next);
/* Also unlocks the rq: */
rq = context_switch(rq, prev, next, &rf);
@@ -6239,7 +6302,7 @@ void __noreturn do_task_dead(void)
/* Tell freezer to ignore us: */
current->flags |= PF_NOFREEZE;
- __schedule(false);
+ __schedule(SM_NONE);
BUG();
/* Avoid "noreturn function does return" - but don't continue if BUG() is a NOP: */
@@ -6300,7 +6363,7 @@ asmlinkage __visible void __sched schedule(void)
sched_submit_work(tsk);
do {
preempt_disable();
- __schedule(false);
+ __schedule(SM_NONE);
sched_preempt_enable_no_resched();
} while (need_resched());
sched_update_worker(tsk);
@@ -6328,7 +6391,7 @@ void __sched schedule_idle(void)
*/
WARN_ON_ONCE(current->__state);
do {
- __schedule(false);
+ __schedule(SM_NONE);
} while (need_resched());
}
@@ -6363,6 +6426,18 @@ void __sched schedule_preempt_disabled(void)
preempt_disable();
}
+#ifdef CONFIG_PREEMPT_RT
+void __sched notrace schedule_rtlock(void)
+{
+ do {
+ preempt_disable();
+ __schedule(SM_RTLOCK_WAIT);
+ sched_preempt_enable_no_resched();
+ } while (need_resched());
+}
+NOKPROBE_SYMBOL(schedule_rtlock);
+#endif
+
static void __sched notrace preempt_schedule_common(void)
{
do {
@@ -6381,7 +6456,7 @@ static void __sched notrace preempt_schedule_common(void)
*/
preempt_disable_notrace();
preempt_latency_start(1);
- __schedule(true);
+ __schedule(SM_PREEMPT);
preempt_latency_stop(1);
preempt_enable_no_resched_notrace();
@@ -6460,7 +6535,7 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
* an infinite recursion.
*/
prev_ctx = exception_enter();
- __schedule(true);
+ __schedule(SM_PREEMPT);
exception_exit(prev_ctx);
preempt_latency_stop(1);
@@ -6609,7 +6684,7 @@ asmlinkage __visible void __sched preempt_schedule_irq(void)
do {
preempt_disable();
local_irq_enable();
- __schedule(true);
+ __schedule(SM_PREEMPT);
local_irq_disable();
sched_preempt_enable_no_resched();
} while (need_resched());
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 5ddd575159fb..e5cdf98f50c2 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1235,7 +1235,7 @@ config PROVE_LOCKING
depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT
select LOCKDEP
select DEBUG_SPINLOCK
- select DEBUG_MUTEXES
+ select DEBUG_MUTEXES if !PREEMPT_RT
select DEBUG_RT_MUTEXES if RT_MUTEXES
select DEBUG_RWSEMS
select DEBUG_WW_MUTEX_SLOWPATH
@@ -1299,7 +1299,7 @@ config LOCK_STAT
depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT
select LOCKDEP
select DEBUG_SPINLOCK
- select DEBUG_MUTEXES
+ select DEBUG_MUTEXES if !PREEMPT_RT
select DEBUG_RT_MUTEXES if RT_MUTEXES
select DEBUG_LOCK_ALLOC
default n
@@ -1335,7 +1335,7 @@ config DEBUG_SPINLOCK
config DEBUG_MUTEXES
bool "Mutex debugging: basic checks"
- depends on DEBUG_KERNEL
+ depends on DEBUG_KERNEL && !PREEMPT_RT
help
This feature allows mutex semantics violations to be detected and
reported.
@@ -1345,7 +1345,8 @@ config DEBUG_WW_MUTEX_SLOWPATH
depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT
select DEBUG_LOCK_ALLOC
select DEBUG_SPINLOCK
- select DEBUG_MUTEXES
+ select DEBUG_MUTEXES if !PREEMPT_RT
+ select DEBUG_RT_MUTEXES if PREEMPT_RT
help
This feature enables slowpath testing for w/w mutex users by
injecting additional -EDEADLK wound/backoff cases. Together with
@@ -1368,7 +1369,7 @@ config DEBUG_LOCK_ALLOC
bool "Lock debugging: detect incorrect freeing of live locks"
depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT
select DEBUG_SPINLOCK
- select DEBUG_MUTEXES
+ select DEBUG_MUTEXES if !PREEMPT_RT
select DEBUG_RT_MUTEXES if RT_MUTEXES
select LOCKDEP
help
diff --git a/lib/test_lockup.c b/lib/test_lockup.c
index 864554e76973..906b598740a7 100644
--- a/lib/test_lockup.c
+++ b/lib/test_lockup.c
@@ -485,13 +485,13 @@ static int __init test_lockup_init(void)
offsetof(spinlock_t, lock.wait_lock.magic),
SPINLOCK_MAGIC) ||
test_magic(lock_rwlock_ptr,
- offsetof(rwlock_t, rtmutex.wait_lock.magic),
+ offsetof(rwlock_t, rwbase.rtmutex.wait_lock.magic),
SPINLOCK_MAGIC) ||
test_magic(lock_mutex_ptr,
- offsetof(struct mutex, lock.wait_lock.magic),
+ offsetof(struct mutex, rtmutex.wait_lock.magic),
SPINLOCK_MAGIC) ||
test_magic(lock_rwsem_ptr,
- offsetof(struct rw_semaphore, rtmutex.wait_lock.magic),
+ offsetof(struct rw_semaphore, rwbase.rtmutex.wait_lock.magic),
SPINLOCK_MAGIC))
return -EINVAL;
#else
@@ -502,7 +502,7 @@ static int __init test_lockup_init(void)
offsetof(rwlock_t, magic),
RWLOCK_MAGIC) ||
test_magic(lock_mutex_ptr,
- offsetof(struct mutex, wait_lock.rlock.magic),
+ offsetof(struct mutex, wait_lock.magic),
SPINLOCK_MAGIC) ||
test_magic(lock_rwsem_ptr,
offsetof(struct rw_semaphore, wait_lock.magic),
diff --git a/scripts/atomic/check-atomics.sh b/scripts/atomic/check-atomics.sh
index 9c7fbd4bcbce..0e7bab3eb0d1 100755
--- a/scripts/atomic/check-atomics.sh
+++ b/scripts/atomic/check-atomics.sh
@@ -14,9 +14,9 @@ if [ $? -ne 0 ]; then
fi
cat <<EOF |
-asm-generic/atomic-instrumented.h
-asm-generic/atomic-long.h
-linux/atomic-arch-fallback.h
+linux/atomic/atomic-instrumented.h
+linux/atomic/atomic-long.h
+linux/atomic/atomic-arch-fallback.h
EOF
while read header; do
OLDSUM="$(tail -n 1 ${LINUXDIR}/include/${header})"
diff --git a/scripts/atomic/fallbacks/acquire b/scripts/atomic/fallbacks/acquire
index 59c00529dc7c..ef764085c79a 100755
--- a/scripts/atomic/fallbacks/acquire
+++ b/scripts/atomic/fallbacks/acquire
@@ -1,8 +1,8 @@
cat <<EOF
static __always_inline ${ret}
-${arch}${atomic}_${pfx}${name}${sfx}_acquire(${params})
+arch_${atomic}_${pfx}${name}${sfx}_acquire(${params})
{
- ${ret} ret = ${arch}${atomic}_${pfx}${name}${sfx}_relaxed(${args});
+ ${ret} ret = arch_${atomic}_${pfx}${name}${sfx}_relaxed(${args});
__atomic_acquire_fence();
return ret;
}
diff --git a/scripts/atomic/fallbacks/add_negative b/scripts/atomic/fallbacks/add_negative
index a66635bceefb..15caa2eb2371 100755
--- a/scripts/atomic/fallbacks/add_negative
+++ b/scripts/atomic/fallbacks/add_negative
@@ -1,6 +1,6 @@
cat <<EOF
/**
- * ${arch}${atomic}_add_negative - add and test if negative
+ * arch_${atomic}_add_negative - add and test if negative
* @i: integer value to add
* @v: pointer of type ${atomic}_t
*
@@ -9,8 +9,8 @@ cat <<EOF
* result is greater than or equal to zero.
*/
static __always_inline bool
-${arch}${atomic}_add_negative(${int} i, ${atomic}_t *v)
+arch_${atomic}_add_negative(${int} i, ${atomic}_t *v)
{
- return ${arch}${atomic}_add_return(i, v) < 0;
+ return arch_${atomic}_add_return(i, v) < 0;
}
EOF
diff --git a/scripts/atomic/fallbacks/add_unless b/scripts/atomic/fallbacks/add_unless
index 2ff598a3f9ec..9e5159c2ccfc 100755
--- a/scripts/atomic/fallbacks/add_unless
+++ b/scripts/atomic/fallbacks/add_unless
@@ -1,6 +1,6 @@
cat << EOF
/**
- * ${arch}${atomic}_add_unless - add unless the number is already a given value
+ * arch_${atomic}_add_unless - add unless the number is already a given value
* @v: pointer of type ${atomic}_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
@@ -9,8 +9,8 @@ cat << EOF
* Returns true if the addition was done.
*/
static __always_inline bool
-${arch}${atomic}_add_unless(${atomic}_t *v, ${int} a, ${int} u)
+arch_${atomic}_add_unless(${atomic}_t *v, ${int} a, ${int} u)
{
- return ${arch}${atomic}_fetch_add_unless(v, a, u) != u;
+ return arch_${atomic}_fetch_add_unless(v, a, u) != u;
}
EOF
diff --git a/scripts/atomic/fallbacks/andnot b/scripts/atomic/fallbacks/andnot
index 3f18663dcefb..5a42f54a3595 100755
--- a/scripts/atomic/fallbacks/andnot
+++ b/scripts/atomic/fallbacks/andnot
@@ -1,7 +1,7 @@
cat <<EOF
static __always_inline ${ret}
-${arch}${atomic}_${pfx}andnot${sfx}${order}(${int} i, ${atomic}_t *v)
+arch_${atomic}_${pfx}andnot${sfx}${order}(${int} i, ${atomic}_t *v)
{
- ${retstmt}${arch}${atomic}_${pfx}and${sfx}${order}(~i, v);
+ ${retstmt}arch_${atomic}_${pfx}and${sfx}${order}(~i, v);
}
EOF
diff --git a/scripts/atomic/fallbacks/dec b/scripts/atomic/fallbacks/dec
index e2e01f0574bb..8c144c818e9e 100755
--- a/scripts/atomic/fallbacks/dec
+++ b/scripts/atomic/fallbacks/dec
@@ -1,7 +1,7 @@
cat <<EOF
static __always_inline ${ret}
-${arch}${atomic}_${pfx}dec${sfx}${order}(${atomic}_t *v)
+arch_${atomic}_${pfx}dec${sfx}${order}(${atomic}_t *v)
{
- ${retstmt}${arch}${atomic}_${pfx}sub${sfx}${order}(1, v);
+ ${retstmt}arch_${atomic}_${pfx}sub${sfx}${order}(1, v);
}
EOF
diff --git a/scripts/atomic/fallbacks/dec_and_test b/scripts/atomic/fallbacks/dec_and_test
index e8a5e492eb5f..8549f359bd0e 100755
--- a/scripts/atomic/fallbacks/dec_and_test
+++ b/scripts/atomic/fallbacks/dec_and_test
@@ -1,6 +1,6 @@
cat <<EOF
/**
- * ${arch}${atomic}_dec_and_test - decrement and test
+ * arch_${atomic}_dec_and_test - decrement and test
* @v: pointer of type ${atomic}_t
*
* Atomically decrements @v by 1 and
@@ -8,8 +8,8 @@ cat <<EOF
* cases.
*/
static __always_inline bool
-${arch}${atomic}_dec_and_test(${atomic}_t *v)
+arch_${atomic}_dec_and_test(${atomic}_t *v)
{
- return ${arch}${atomic}_dec_return(v) == 0;
+ return arch_${atomic}_dec_return(v) == 0;
}
EOF
diff --git a/scripts/atomic/fallbacks/dec_if_positive b/scripts/atomic/fallbacks/dec_if_positive
index 527adec89c37..86bdced3428d 100755
--- a/scripts/atomic/fallbacks/dec_if_positive
+++ b/scripts/atomic/fallbacks/dec_if_positive
@@ -1,14 +1,14 @@
cat <<EOF
static __always_inline ${ret}
-${arch}${atomic}_dec_if_positive(${atomic}_t *v)
+arch_${atomic}_dec_if_positive(${atomic}_t *v)
{
- ${int} dec, c = ${arch}${atomic}_read(v);
+ ${int} dec, c = arch_${atomic}_read(v);
do {
dec = c - 1;
if (unlikely(dec < 0))
break;
- } while (!${arch}${atomic}_try_cmpxchg(v, &c, dec));
+ } while (!arch_${atomic}_try_cmpxchg(v, &c, dec));
return dec;
}
diff --git a/scripts/atomic/fallbacks/dec_unless_positive b/scripts/atomic/fallbacks/dec_unless_positive
index dcab6848ca1e..c531d5afecc4 100755
--- a/scripts/atomic/fallbacks/dec_unless_positive
+++ b/scripts/atomic/fallbacks/dec_unless_positive
@@ -1,13 +1,13 @@
cat <<EOF
static __always_inline bool
-${arch}${atomic}_dec_unless_positive(${atomic}_t *v)
+arch_${atomic}_dec_unless_positive(${atomic}_t *v)
{
- ${int} c = ${arch}${atomic}_read(v);
+ ${int} c = arch_${atomic}_read(v);
do {
if (unlikely(c > 0))
return false;
- } while (!${arch}${atomic}_try_cmpxchg(v, &c, c - 1));
+ } while (!arch_${atomic}_try_cmpxchg(v, &c, c - 1));
return true;
}
diff --git a/scripts/atomic/fallbacks/fence b/scripts/atomic/fallbacks/fence
index 3764fc8ce945..07757d8e338e 100755
--- a/scripts/atomic/fallbacks/fence
+++ b/scripts/atomic/fallbacks/fence
@@ -1,10 +1,10 @@
cat <<EOF
static __always_inline ${ret}
-${arch}${atomic}_${pfx}${name}${sfx}(${params})
+arch_${atomic}_${pfx}${name}${sfx}(${params})
{
${ret} ret;
__atomic_pre_full_fence();
- ret = ${arch}${atomic}_${pfx}${name}${sfx}_relaxed(${args});
+ ret = arch_${atomic}_${pfx}${name}${sfx}_relaxed(${args});
__atomic_post_full_fence();
return ret;
}
diff --git a/scripts/atomic/fallbacks/fetch_add_unless b/scripts/atomic/fallbacks/fetch_add_unless
index 0e0b9aef1515..68ce13c8b9da 100755
--- a/scripts/atomic/fallbacks/fetch_add_unless
+++ b/scripts/atomic/fallbacks/fetch_add_unless
@@ -1,6 +1,6 @@
cat << EOF
/**
- * ${arch}${atomic}_fetch_add_unless - add unless the number is already a given value
+ * arch_${atomic}_fetch_add_unless - add unless the number is already a given value
* @v: pointer of type ${atomic}_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
@@ -9,14 +9,14 @@ cat << EOF
* Returns original value of @v
*/
static __always_inline ${int}
-${arch}${atomic}_fetch_add_unless(${atomic}_t *v, ${int} a, ${int} u)
+arch_${atomic}_fetch_add_unless(${atomic}_t *v, ${int} a, ${int} u)
{
- ${int} c = ${arch}${atomic}_read(v);
+ ${int} c = arch_${atomic}_read(v);
do {
if (unlikely(c == u))
break;
- } while (!${arch}${atomic}_try_cmpxchg(v, &c, c + a));
+ } while (!arch_${atomic}_try_cmpxchg(v, &c, c + a));
return c;
}
diff --git a/scripts/atomic/fallbacks/inc b/scripts/atomic/fallbacks/inc
index 15ec62946e8c..3c2c3739169e 100755
--- a/scripts/atomic/fallbacks/inc
+++ b/scripts/atomic/fallbacks/inc
@@ -1,7 +1,7 @@
cat <<EOF
static __always_inline ${ret}
-${arch}${atomic}_${pfx}inc${sfx}${order}(${atomic}_t *v)
+arch_${atomic}_${pfx}inc${sfx}${order}(${atomic}_t *v)
{
- ${retstmt}${arch}${atomic}_${pfx}add${sfx}${order}(1, v);
+ ${retstmt}arch_${atomic}_${pfx}add${sfx}${order}(1, v);
}
EOF
diff --git a/scripts/atomic/fallbacks/inc_and_test b/scripts/atomic/fallbacks/inc_and_test
index cecc8322a21f..0cf23fe1efb8 100755
--- a/scripts/atomic/fallbacks/inc_and_test
+++ b/scripts/atomic/fallbacks/inc_and_test
@@ -1,6 +1,6 @@
cat <<EOF
/**
- * ${arch}${atomic}_inc_and_test - increment and test
+ * arch_${atomic}_inc_and_test - increment and test
* @v: pointer of type ${atomic}_t
*
* Atomically increments @v by 1
@@ -8,8 +8,8 @@ cat <<EOF
* other cases.
*/
static __always_inline bool
-${arch}${atomic}_inc_and_test(${atomic}_t *v)
+arch_${atomic}_inc_and_test(${atomic}_t *v)
{
- return ${arch}${atomic}_inc_return(v) == 0;
+ return arch_${atomic}_inc_return(v) == 0;
}
EOF
diff --git a/scripts/atomic/fallbacks/inc_not_zero b/scripts/atomic/fallbacks/inc_not_zero
index 50f2d4d48279..ed8a1f562667 100755
--- a/scripts/atomic/fallbacks/inc_not_zero
+++ b/scripts/atomic/fallbacks/inc_not_zero
@@ -1,14 +1,14 @@
cat <<EOF
/**
- * ${arch}${atomic}_inc_not_zero - increment unless the number is zero
+ * arch_${atomic}_inc_not_zero - increment unless the number is zero
* @v: pointer of type ${atomic}_t
*
* Atomically increments @v by 1, if @v is non-zero.
* Returns true if the increment was done.
*/
static __always_inline bool
-${arch}${atomic}_inc_not_zero(${atomic}_t *v)
+arch_${atomic}_inc_not_zero(${atomic}_t *v)
{
- return ${arch}${atomic}_add_unless(v, 1, 0);
+ return arch_${atomic}_add_unless(v, 1, 0);
}
EOF
diff --git a/scripts/atomic/fallbacks/inc_unless_negative b/scripts/atomic/fallbacks/inc_unless_negative
index 87629e0d4a80..95d8ce48233f 100755
--- a/scripts/atomic/fallbacks/inc_unless_negative
+++ b/scripts/atomic/fallbacks/inc_unless_negative
@@ -1,13 +1,13 @@
cat <<EOF
static __always_inline bool
-${arch}${atomic}_inc_unless_negative(${atomic}_t *v)
+arch_${atomic}_inc_unless_negative(${atomic}_t *v)
{
- ${int} c = ${arch}${atomic}_read(v);
+ ${int} c = arch_${atomic}_read(v);
do {
if (unlikely(c < 0))
return false;
- } while (!${arch}${atomic}_try_cmpxchg(v, &c, c + 1));
+ } while (!arch_${atomic}_try_cmpxchg(v, &c, c + 1));
return true;
}
diff --git a/scripts/atomic/fallbacks/read_acquire b/scripts/atomic/fallbacks/read_acquire
index 341a88dccaa7..803ba7561076 100755
--- a/scripts/atomic/fallbacks/read_acquire
+++ b/scripts/atomic/fallbacks/read_acquire
@@ -1,6 +1,6 @@
cat <<EOF
static __always_inline ${ret}
-${arch}${atomic}_read_acquire(const ${atomic}_t *v)
+arch_${atomic}_read_acquire(const ${atomic}_t *v)
{
return smp_load_acquire(&(v)->counter);
}
diff --git a/scripts/atomic/fallbacks/release b/scripts/atomic/fallbacks/release
index f8906d537c0f..b46feb56d69c 100755
--- a/scripts/atomic/fallbacks/release
+++ b/scripts/atomic/fallbacks/release
@@ -1,8 +1,8 @@
cat <<EOF
static __always_inline ${ret}
-${arch}${atomic}_${pfx}${name}${sfx}_release(${params})
+arch_${atomic}_${pfx}${name}${sfx}_release(${params})
{
__atomic_release_fence();
- ${retstmt}${arch}${atomic}_${pfx}${name}${sfx}_relaxed(${args});
+ ${retstmt}arch_${atomic}_${pfx}${name}${sfx}_relaxed(${args});
}
EOF
diff --git a/scripts/atomic/fallbacks/set_release b/scripts/atomic/fallbacks/set_release
index 76068272d5f5..86ede759f24e 100755
--- a/scripts/atomic/fallbacks/set_release
+++ b/scripts/atomic/fallbacks/set_release
@@ -1,6 +1,6 @@
cat <<EOF
static __always_inline void
-${arch}${atomic}_set_release(${atomic}_t *v, ${int} i)
+arch_${atomic}_set_release(${atomic}_t *v, ${int} i)
{
smp_store_release(&(v)->counter, i);
}
diff --git a/scripts/atomic/fallbacks/sub_and_test b/scripts/atomic/fallbacks/sub_and_test
index c580f4c2136e..260f37341c88 100755
--- a/scripts/atomic/fallbacks/sub_and_test
+++ b/scripts/atomic/fallbacks/sub_and_test
@@ -1,6 +1,6 @@
cat <<EOF
/**
- * ${arch}${atomic}_sub_and_test - subtract value from variable and test result
+ * arch_${atomic}_sub_and_test - subtract value from variable and test result
* @i: integer value to subtract
* @v: pointer of type ${atomic}_t
*
@@ -9,8 +9,8 @@ cat <<EOF
* other cases.
*/
static __always_inline bool
-${arch}${atomic}_sub_and_test(${int} i, ${atomic}_t *v)
+arch_${atomic}_sub_and_test(${int} i, ${atomic}_t *v)
{
- return ${arch}${atomic}_sub_return(i, v) == 0;
+ return arch_${atomic}_sub_return(i, v) == 0;
}
EOF
diff --git a/scripts/atomic/fallbacks/try_cmpxchg b/scripts/atomic/fallbacks/try_cmpxchg
index 06db0f738e45..890f850ede37 100755
--- a/scripts/atomic/fallbacks/try_cmpxchg
+++ b/scripts/atomic/fallbacks/try_cmpxchg
@@ -1,9 +1,9 @@
cat <<EOF
static __always_inline bool
-${arch}${atomic}_try_cmpxchg${order}(${atomic}_t *v, ${int} *old, ${int} new)
+arch_${atomic}_try_cmpxchg${order}(${atomic}_t *v, ${int} *old, ${int} new)
{
${int} r, o = *old;
- r = ${arch}${atomic}_cmpxchg${order}(v, o, new);
+ r = arch_${atomic}_cmpxchg${order}(v, o, new);
if (unlikely(r != o))
*old = r;
return likely(r == o);
diff --git a/scripts/atomic/gen-atomic-fallback.sh b/scripts/atomic/gen-atomic-fallback.sh
index 317a6cec76e1..8e2da71f1d5f 100755
--- a/scripts/atomic/gen-atomic-fallback.sh
+++ b/scripts/atomic/gen-atomic-fallback.sh
@@ -2,11 +2,10 @@
# SPDX-License-Identifier: GPL-2.0
ATOMICDIR=$(dirname $0)
-ARCH=$2
. ${ATOMICDIR}/atomic-tbl.sh
-#gen_template_fallback(template, meta, pfx, name, sfx, order, arch, atomic, int, args...)
+#gen_template_fallback(template, meta, pfx, name, sfx, order, atomic, int, args...)
gen_template_fallback()
{
local template="$1"; shift
@@ -15,11 +14,10 @@ gen_template_fallback()
local name="$1"; shift
local sfx="$1"; shift
local order="$1"; shift
- local arch="$1"; shift
local atomic="$1"; shift
local int="$1"; shift
- local atomicname="${arch}${atomic}_${pfx}${name}${sfx}${order}"
+ local atomicname="arch_${atomic}_${pfx}${name}${sfx}${order}"
local ret="$(gen_ret_type "${meta}" "${int}")"
local retstmt="$(gen_ret_stmt "${meta}")"
@@ -34,7 +32,7 @@ gen_template_fallback()
fi
}
-#gen_proto_fallback(meta, pfx, name, sfx, order, arch, atomic, int, args...)
+#gen_proto_fallback(meta, pfx, name, sfx, order, atomic, int, args...)
gen_proto_fallback()
{
local meta="$1"; shift
@@ -65,44 +63,26 @@ gen_proto_order_variant()
local name="$1"; shift
local sfx="$1"; shift
local order="$1"; shift
- local arch="$1"
- local atomic="$2"
+ local atomic="$1"
- local basename="${arch}${atomic}_${pfx}${name}${sfx}"
+ local basename="arch_${atomic}_${pfx}${name}${sfx}"
- printf "#define arch_${basename}${order} ${basename}${order}\n"
+ printf "#define ${basename}${order} ${basename}${order}\n"
}
-#gen_proto_order_variants(meta, pfx, name, sfx, arch, atomic, int, args...)
+#gen_proto_order_variants(meta, pfx, name, sfx, atomic, int, args...)
gen_proto_order_variants()
{
local meta="$1"; shift
local pfx="$1"; shift
local name="$1"; shift
local sfx="$1"; shift
- local arch="$1"
- local atomic="$2"
+ local atomic="$1"
- local basename="${arch}${atomic}_${pfx}${name}${sfx}"
+ local basename="arch_${atomic}_${pfx}${name}${sfx}"
local template="$(find_fallback_template "${pfx}" "${name}" "${sfx}" "${order}")"
- if [ -z "$arch" ]; then
- gen_proto_order_variant "${meta}" "${pfx}" "${name}" "${sfx}" "" "$@"
-
- if meta_has_acquire "${meta}"; then
- gen_proto_order_variant "${meta}" "${pfx}" "${name}" "${sfx}" "_acquire" "$@"
- fi
- if meta_has_release "${meta}"; then
- gen_proto_order_variant "${meta}" "${pfx}" "${name}" "${sfx}" "_release" "$@"
- fi
- if meta_has_relaxed "${meta}"; then
- gen_proto_order_variant "${meta}" "${pfx}" "${name}" "${sfx}" "_relaxed" "$@"
- fi
-
- echo ""
- fi
-
# If we don't have relaxed atomics, then we don't bother with ordering fallbacks
# read_acquire and set_release need to be templated, though
if ! meta_has_relaxed "${meta}"; then
@@ -128,7 +108,7 @@ gen_proto_order_variants()
gen_basic_fallbacks "${basename}"
if [ ! -z "${template}" ]; then
- printf "#endif /* ${arch}${atomic}_${pfx}${name}${sfx} */\n\n"
+ printf "#endif /* ${basename} */\n\n"
gen_proto_fallback "${meta}" "${pfx}" "${name}" "${sfx}" "" "$@"
gen_proto_fallback "${meta}" "${pfx}" "${name}" "${sfx}" "_acquire" "$@"
gen_proto_fallback "${meta}" "${pfx}" "${name}" "${sfx}" "_release" "$@"
@@ -187,38 +167,38 @@ gen_try_cmpxchg_fallback()
local order="$1"; shift;
cat <<EOF
-#ifndef ${ARCH}try_cmpxchg${order}
-#define ${ARCH}try_cmpxchg${order}(_ptr, _oldp, _new) \\
+#ifndef arch_try_cmpxchg${order}
+#define arch_try_cmpxchg${order}(_ptr, _oldp, _new) \\
({ \\
typeof(*(_ptr)) *___op = (_oldp), ___o = *___op, ___r; \\
- ___r = ${ARCH}cmpxchg${order}((_ptr), ___o, (_new)); \\
+ ___r = arch_cmpxchg${order}((_ptr), ___o, (_new)); \\
if (unlikely(___r != ___o)) \\
*___op = ___r; \\
likely(___r == ___o); \\
})
-#endif /* ${ARCH}try_cmpxchg${order} */
+#endif /* arch_try_cmpxchg${order} */
EOF
}
gen_try_cmpxchg_fallbacks()
{
- printf "#ifndef ${ARCH}try_cmpxchg_relaxed\n"
- printf "#ifdef ${ARCH}try_cmpxchg\n"
+ printf "#ifndef arch_try_cmpxchg_relaxed\n"
+ printf "#ifdef arch_try_cmpxchg\n"
- gen_basic_fallbacks "${ARCH}try_cmpxchg"
+ gen_basic_fallbacks "arch_try_cmpxchg"
- printf "#endif /* ${ARCH}try_cmpxchg */\n\n"
+ printf "#endif /* arch_try_cmpxchg */\n\n"
for order in "" "_acquire" "_release" "_relaxed"; do
gen_try_cmpxchg_fallback "${order}"
done
- printf "#else /* ${ARCH}try_cmpxchg_relaxed */\n"
+ printf "#else /* arch_try_cmpxchg_relaxed */\n"
- gen_order_fallbacks "${ARCH}try_cmpxchg"
+ gen_order_fallbacks "arch_try_cmpxchg"
- printf "#endif /* ${ARCH}try_cmpxchg_relaxed */\n\n"
+ printf "#endif /* arch_try_cmpxchg_relaxed */\n\n"
}
cat << EOF
@@ -234,14 +214,14 @@ cat << EOF
EOF
-for xchg in "${ARCH}xchg" "${ARCH}cmpxchg" "${ARCH}cmpxchg64"; do
+for xchg in "arch_xchg" "arch_cmpxchg" "arch_cmpxchg64"; do
gen_xchg_fallbacks "${xchg}"
done
gen_try_cmpxchg_fallbacks
grep '^[a-z]' "$1" | while read name meta args; do
- gen_proto "${meta}" "${name}" "${ARCH}" "atomic" "int" ${args}
+ gen_proto "${meta}" "${name}" "atomic" "int" ${args}
done
cat <<EOF
@@ -252,7 +232,7 @@ cat <<EOF
EOF
grep '^[a-z]' "$1" | while read name meta args; do
- gen_proto "${meta}" "${name}" "${ARCH}" "atomic64" "s64" ${args}
+ gen_proto "${meta}" "${name}" "atomic64" "s64" ${args}
done
cat <<EOF
diff --git a/scripts/atomic/gen-atomic-instrumented.sh b/scripts/atomic/gen-atomic-instrumented.sh
index b0c45aee19d7..035ceb4ee85c 100755
--- a/scripts/atomic/gen-atomic-instrumented.sh
+++ b/scripts/atomic/gen-atomic-instrumented.sh
@@ -121,8 +121,8 @@ cat << EOF
* arch_ variants (i.e. arch_atomic_read()/arch_atomic_cmpxchg()) to avoid
* double instrumentation.
*/
-#ifndef _ASM_GENERIC_ATOMIC_INSTRUMENTED_H
-#define _ASM_GENERIC_ATOMIC_INSTRUMENTED_H
+#ifndef _LINUX_ATOMIC_INSTRUMENTED_H
+#define _LINUX_ATOMIC_INSTRUMENTED_H
#include <linux/build_bug.h>
#include <linux/compiler.h>
@@ -138,6 +138,11 @@ grep '^[a-z]' "$1" | while read name meta args; do
gen_proto "${meta}" "${name}" "atomic64" "s64" ${args}
done
+grep '^[a-z]' "$1" | while read name meta args; do
+ gen_proto "${meta}" "${name}" "atomic_long" "long" ${args}
+done
+
+
for xchg in "xchg" "cmpxchg" "cmpxchg64" "try_cmpxchg"; do
for order in "" "_acquire" "_release" "_relaxed"; do
gen_xchg "${xchg}${order}" ""
@@ -158,5 +163,5 @@ gen_xchg "cmpxchg_double_local" "2 * "
cat <<EOF
-#endif /* _ASM_GENERIC_ATOMIC_INSTRUMENTED_H */
+#endif /* _LINUX_ATOMIC_INSTRUMENTED_H */
EOF
diff --git a/scripts/atomic/gen-atomic-long.sh b/scripts/atomic/gen-atomic-long.sh
index e318d3f92e53..eda89cea6e1d 100755
--- a/scripts/atomic/gen-atomic-long.sh
+++ b/scripts/atomic/gen-atomic-long.sh
@@ -47,9 +47,9 @@ gen_proto_order_variant()
cat <<EOF
static __always_inline ${ret}
-atomic_long_${name}(${params})
+arch_atomic_long_${name}(${params})
{
- ${retstmt}${atomic}_${name}(${argscast});
+ ${retstmt}arch_${atomic}_${name}(${argscast});
}
EOF
@@ -61,8 +61,8 @@ cat << EOF
// Generated by $0
// DO NOT MODIFY THIS FILE DIRECTLY
-#ifndef _ASM_GENERIC_ATOMIC_LONG_H
-#define _ASM_GENERIC_ATOMIC_LONG_H
+#ifndef _LINUX_ATOMIC_LONG_H
+#define _LINUX_ATOMIC_LONG_H
#include <linux/compiler.h>
#include <asm/types.h>
@@ -98,5 +98,5 @@ done
cat <<EOF
#endif /* CONFIG_64BIT */
-#endif /* _ASM_GENERIC_ATOMIC_LONG_H */
+#endif /* _LINUX_ATOMIC_LONG_H */
EOF
diff --git a/scripts/atomic/gen-atomics.sh b/scripts/atomic/gen-atomics.sh
index f776a574224d..5b98a8307693 100755
--- a/scripts/atomic/gen-atomics.sh
+++ b/scripts/atomic/gen-atomics.sh
@@ -8,9 +8,9 @@ ATOMICTBL=${ATOMICDIR}/atomics.tbl
LINUXDIR=${ATOMICDIR}/../..
cat <<EOF |
-gen-atomic-instrumented.sh asm-generic/atomic-instrumented.h
-gen-atomic-long.sh asm-generic/atomic-long.h
-gen-atomic-fallback.sh linux/atomic-arch-fallback.h arch_
+gen-atomic-instrumented.sh linux/atomic/atomic-instrumented.h
+gen-atomic-long.sh linux/atomic/atomic-long.h
+gen-atomic-fallback.sh linux/atomic/atomic-arch-fallback.h
EOF
while read script header args; do
/bin/sh ${ATOMICDIR}/${script} ${ATOMICTBL} ${args} > ${LINUXDIR}/include/${header}