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: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210809021215.19991-1-nixiaoming@huawei.com

diff --git a/kernel/locking/semaphore.c b/kernel/locking/semaphore.c
index 9aa855a..9ee381e 100644 (file)
--- 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--;