diff options
author | Davidlohr Bueso <dave@stgolabs.net> | 2014-09-29 06:14:23 -0700 |
---|---|---|
committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2014-09-30 00:10:00 -0700 |
commit | e34191fad8e5d9fe4e76f6d03b5e29e3eae7535a (patch) | |
tree | bdf4b88a473d2a7c416cf44dc826cb8393cb0b4a /kernel/locking | |
parent | dd56af42bd829c6e770ed69812bd65a04eaeb1e4 (diff) | |
download | linux-next-e34191fad8e5d9fe4e76f6d03b5e29e3eae7535a.tar.gz |
locktorture: Support rwlocks
Add a "rw_lock" torture test to stress kernel rwlocks and their irq
variant. Reader critical regions are 5x longer than writers. As such
a similar ratio of lock acquisitions is seen in the statistics. In the
case of massive contention, both hold the lock for 1/10 of a second.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'kernel/locking')
-rw-r--r-- | kernel/locking/locktorture.c | 115 |
1 files changed, 112 insertions, 3 deletions
diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c index 540d5dfe1112..0762b25b4110 100644 --- a/kernel/locking/locktorture.c +++ b/kernel/locking/locktorture.c @@ -27,6 +27,7 @@ #include <linux/kthread.h> #include <linux/err.h> #include <linux/spinlock.h> +#include <linux/rwlock.h> #include <linux/mutex.h> #include <linux/smp.h> #include <linux/interrupt.h> @@ -229,6 +230,110 @@ static struct lock_torture_ops spin_lock_irq_ops = { .name = "spin_lock_irq" }; +static DEFINE_RWLOCK(torture_rwlock); + +static int torture_rwlock_write_lock(void) __acquires(torture_rwlock) +{ + write_lock(&torture_rwlock); + return 0; +} + +static void torture_rwlock_write_delay(struct torture_random_state *trsp) +{ + const unsigned long shortdelay_us = 2; + const unsigned long longdelay_ms = 100; + + /* We want a short delay mostly to emulate likely code, and + * we want a long delay occasionally to force massive contention. + */ + if (!(torture_random(trsp) % + (cxt.nrealwriters_stress * 2000 * longdelay_ms))) + mdelay(longdelay_ms); + else + udelay(shortdelay_us); +} + +static void torture_rwlock_write_unlock(void) __releases(torture_rwlock) +{ + write_unlock(&torture_rwlock); +} + +static int torture_rwlock_read_lock(void) __acquires(torture_rwlock) +{ + read_lock(&torture_rwlock); + return 0; +} + +static void torture_rwlock_read_delay(struct torture_random_state *trsp) +{ + const unsigned long shortdelay_us = 10; + const unsigned long longdelay_ms = 100; + + /* We want a short delay mostly to emulate likely code, and + * we want a long delay occasionally to force massive contention. + */ + if (!(torture_random(trsp) % + (cxt.nrealreaders_stress * 2000 * longdelay_ms))) + mdelay(longdelay_ms); + else + udelay(shortdelay_us); +} + +static void torture_rwlock_read_unlock(void) __releases(torture_rwlock) +{ + read_unlock(&torture_rwlock); +} + +static struct lock_torture_ops rw_lock_ops = { + .writelock = torture_rwlock_write_lock, + .write_delay = torture_rwlock_write_delay, + .writeunlock = torture_rwlock_write_unlock, + .readlock = torture_rwlock_read_lock, + .read_delay = torture_rwlock_read_delay, + .readunlock = torture_rwlock_read_unlock, + .name = "rw_lock" +}; + +static int torture_rwlock_write_lock_irq(void) __acquires(torture_rwlock) +{ + unsigned long flags; + + write_lock_irqsave(&torture_rwlock, flags); + cxt.cur_ops->flags = flags; + return 0; +} + +static void torture_rwlock_write_unlock_irq(void) +__releases(torture_rwlock) +{ + write_unlock_irqrestore(&torture_rwlock, cxt.cur_ops->flags); +} + +static int torture_rwlock_read_lock_irq(void) __acquires(torture_rwlock) +{ + unsigned long flags; + + read_lock_irqsave(&torture_rwlock, flags); + cxt.cur_ops->flags = flags; + return 0; +} + +static void torture_rwlock_read_unlock_irq(void) +__releases(torture_rwlock) +{ + write_unlock_irqrestore(&torture_rwlock, cxt.cur_ops->flags); +} + +static struct lock_torture_ops rw_lock_irq_ops = { + .writelock = torture_rwlock_write_lock_irq, + .write_delay = torture_rwlock_write_delay, + .writeunlock = torture_rwlock_write_unlock_irq, + .readlock = torture_rwlock_read_lock_irq, + .read_delay = torture_rwlock_read_delay, + .readunlock = torture_rwlock_read_unlock_irq, + .name = "rw_lock_irq" +}; + static DEFINE_MUTEX(torture_mutex); static int torture_mutex_lock(void) __acquires(torture_mutex) @@ -535,8 +640,11 @@ static int __init lock_torture_init(void) int i, j; int firsterr = 0; static struct lock_torture_ops *torture_ops[] = { - &lock_busted_ops, &spin_lock_ops, &spin_lock_irq_ops, - &mutex_lock_ops, &rwsem_lock_ops, + &lock_busted_ops, + &spin_lock_ops, &spin_lock_irq_ops, + &rw_lock_ops, &rw_lock_irq_ops, + &mutex_lock_ops, + &rwsem_lock_ops, }; if (!torture_init_begin(torture_type, verbose, &torture_runnable)) @@ -571,7 +679,8 @@ static int __init lock_torture_init(void) cxt.debug_lock = true; #endif #ifdef CONFIG_DEBUG_SPINLOCK - if (strncmp(torture_type, "spin", 4) == 0) + if ((strncmp(torture_type, "spin", 4) == 0) || + (strncmp(torture_type, "rw_lock", 7) == 0)) cxt.debug_lock = true; #endif |