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authorUlrich Drepper <drepper@redhat.com>2006-08-14 23:11:18 +0000
committerUlrich Drepper <drepper@redhat.com>2006-08-14 23:11:18 +0000
commitf17efcb43e500d4af62b71bd6f286af831069b5a (patch)
treebf062a11f158b5bc8e33e42cc85e625751bacf94 /nptl/pthread_mutex_setprioceiling.c
parent107b8a922a9f72bae8d066549c675062bee0897f (diff)
downloadglibc-f17efcb43e500d4af62b71bd6f286af831069b5a.tar.gz
* sysdeps/powerpc/powerpc32/dl-trampoline.S (_dl_runtime_resolve):
Don't clobber caller's LRSAVE. (_dl_prof_resolve): Likewise.
Diffstat (limited to 'nptl/pthread_mutex_setprioceiling.c')
-rw-r--r--nptl/pthread_mutex_setprioceiling.c81
1 files changed, 71 insertions, 10 deletions
diff --git a/nptl/pthread_mutex_setprioceiling.c b/nptl/pthread_mutex_setprioceiling.c
index 3271f8833a..cd13d1c14c 100644
--- a/nptl/pthread_mutex_setprioceiling.c
+++ b/nptl/pthread_mutex_setprioceiling.c
@@ -18,6 +18,7 @@
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
+#include <stdbool.h>
#include <errno.h>
#include <pthreadP.h>
@@ -33,23 +34,83 @@ pthread_mutex_setprioceiling (mutex, prioceiling, old_ceiling)
if ((mutex->__data.__kind & PTHREAD_MUTEX_PRIO_PROTECT_NP) == 0)
return EINVAL;
- if (prioceiling < 0 || __builtin_expect (prioceiling > 255, 0))
+ if (__sched_fifo_min_prio == -1)
+ __init_sched_fifo_prio ();
+
+ if (__builtin_expect (prioceiling < __sched_fifo_min_prio, 0)
+ || __builtin_expect (prioceiling > __sched_fifo_max_prio, 0)
+ || __builtin_expect ((prioceiling
+ & (PTHREAD_MUTEXATTR_PRIO_CEILING_MASK
+ >> PTHREAD_MUTEXATTR_PRIO_CEILING_SHIFT))
+ != prioceiling, 0))
return EINVAL;
- /* XXX This needs to lock with TID, but shouldn't obey priority protect
- protocol. */
- /* lll_xxx_mutex_lock (mutex->__data.__lock); */
+ /* Check whether we already hold the mutex. */
+ bool locked = false;
+ if (mutex->__data.__owner == THREAD_GETMEM (THREAD_SELF, tid))
+ {
+ if (mutex->__data.__kind == PTHREAD_MUTEX_PP_ERRORCHECK_NP)
+ return EDEADLK;
+
+ if (mutex->__data.__kind == PTHREAD_MUTEX_PP_RECURSIVE_NP)
+ locked = true;
+ }
+
+ int oldval = mutex->__data.__lock;
+ if (! locked)
+ do
+ {
+ /* Need to lock the mutex, but without obeying the priority
+ protect protocol. */
+ int ceilval = (oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK);
+
+ oldval = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock,
+ ceilval | 1, ceilval);
+ if (oldval == ceilval)
+ break;
+
+ do
+ {
+ oldval
+ = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock,
+ ceilval | 2,
+ ceilval | 1);
+
+ if ((oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK) != ceilval)
+ break;
+
+ if (oldval != ceilval)
+ lll_futex_wait (&mutex->__data.__lock, ceilval | 2);
+ }
+ while (atomic_compare_and_exchange_val_acq (&mutex->__data.__lock,
+ ceilval | 2, ceilval)
+ != ceilval);
+
+ if ((oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK) != ceilval)
+ continue;
+ }
+ while (0);
+
+ int oldprio = (oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK)
+ >> PTHREAD_MUTEX_PRIO_CEILING_SHIFT;
+ if (locked)
+ {
+ int ret = __pthread_tpp_change_priority (oldprio, prioceiling);
+ if (ret)
+ return ret;
+ }
if (old_ceiling != NULL)
- *old_ceiling = (mutex->__data.__kind & PTHREAD_MUTEX_PRIO_CEILING_MASK)
- >> PTHREAD_MUTEX_PRIO_CEILING_SHIFT;
+ *old_ceiling = oldprio;
- int newkind = (mutex->__data.__kind & ~PTHREAD_MUTEX_PRIO_CEILING_MASK);
- mutex->__data.__kind = newkind
+ int newlock = 0;
+ if (locked)
+ newlock = (mutex->__data.__lock & ~PTHREAD_MUTEX_PRIO_CEILING_MASK);
+ mutex->__data.__lock = newlock
| (prioceiling << PTHREAD_MUTEX_PRIO_CEILING_SHIFT);
+ atomic_full_barrier ();
- /* XXX This needs to unlock the above special kind of lock. */
- /* lll_xxx_mutex_unlock (mutex->__data.__lock); */
+ lll_futex_wake (&mutex->__data.__lock, INT_MAX);
return 0;
}