Commit 99409b93 authored by Xiaoming Ni's avatar Xiaoming Ni Committed by Peter Zijlstra
Browse files

locking/semaphore: Add might_sleep() to down_*() family 



Semaphore is sleeping lock. Add might_sleep() to down*() family
(with exception of down_trylock()) to detect atomic context sleep.

Signed-off-by: default avatarXiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: default avatarWill Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210809021215.19991-1-nixiaoming@huawei.com
parent b857174e

kernel/locking/semaphore.c

+4 −0
Original line number Diff line number Diff line
@@ -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--;