diff options
Diffstat (limited to 'kernel/locking/mutex.c')
| -rw-r--r-- | kernel/locking/mutex.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c index d973fe6041bf..cbae8c0b89ab 100644 --- a/kernel/locking/mutex.c +++ b/kernel/locking/mutex.c @@ -532,6 +532,11 @@ static noinline void __sched __mutex_unlock_slowpath(struct mutex *lock, unsigne * This function must not be used in interrupt context. Unlocking * of a not locked mutex is not allowed. * + * The caller must ensure that the mutex stays alive until this function has + * returned - mutex_unlock() can NOT directly be used to release an object such + * that another concurrent task can free it. + * Mutexes are different from spinlocks & refcounts in this aspect. + * * This function is similar to (but not equivalent to) up(). */ void __sched mutex_unlock(struct mutex *lock) @@ -1126,6 +1131,9 @@ EXPORT_SYMBOL(ww_mutex_lock_interruptible); #endif /* !CONFIG_DEBUG_LOCK_ALLOC */ #endif /* !CONFIG_PREEMPT_RT */ +EXPORT_TRACEPOINT_SYMBOL_GPL(contention_begin); +EXPORT_TRACEPOINT_SYMBOL_GPL(contention_end); + /** * atomic_dec_and_mutex_lock - return holding mutex if we dec to 0 * @cnt: the atomic which we are to dec |