The percpu_rwsem_release() is called when the ownership of the embedded
rwsem is to be transferred to another task. The new owner, however, may
take a while to get the ownership of the lock via percpu_rwsem_acquire().
During that period, the rwsem is now marked as writer-owned with no
optimistic spinning.
Signed-off-by: Waiman Long <longman@xxxxxxxxxx>
---
include/linux/percpu-rwsem.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/include/linux/percpu-rwsem.h b/include/linux/percpu-rwsem.h
index b1f37a8..dd37102 100644
--- a/include/linux/percpu-rwsem.h
+++ b/include/linux/percpu-rwsem.h
@@ -131,16 +131,16 @@ static inline void percpu_rwsem_release(struct percpu_rw_semaphore *sem,
bool read, unsigned long ip)
{
lock_release(&sem->rw_sem.dep_map, 1, ip);
-#ifdef CONFIG_RWSEM_SPIN_ON_OWNER
if (!read)
- sem->rw_sem.owner = NULL;
-#endif
+ rwsem_set_writer_owned_nospin(&sem->rw_sem);
}
static inline void percpu_rwsem_acquire(struct percpu_rw_semaphore *sem,
bool read, unsigned long ip)
{
lock_acquire(&sem->rw_sem.dep_map, 0, 1, read, 1, NULL, ip);
+ if (!read)
+ rwsem_set_writer_owned(&sem->rw_sem, current);
}
#endif
--
1.8.3.1
