diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/rwsem-spinlock.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/lib/rwsem-spinlock.c b/lib/rwsem-spinlock.c index 39a74110f55..ccf95bff798 100644 --- a/lib/rwsem-spinlock.c +++ b/lib/rwsem-spinlock.c @@ -17,6 +17,19 @@ struct rwsem_waiter { #define RWSEM_WAITING_FOR_WRITE 0x00000002 }; +int rwsem_is_locked(struct rw_semaphore *sem) +{ + int ret = 1; + unsigned long flags; + + if (spin_trylock_irqsave(&sem->wait_lock, flags)) { + ret = (sem->activity != 0); + spin_unlock_irqrestore(&sem->wait_lock, flags); + } + return ret; +} +EXPORT_SYMBOL(rwsem_is_locked); + /* * initialise the semaphore */ |