[PATCH] locking/rwsem: Remove unnessary check in rwsem_down_read_slowpath()

From: Haifeng Xu
Date: Wed Nov 08 2023 - 05:57:32 EST


When the owner of rw_semaphore is reader, the count can't be
RWSEM_WRITER_LOCKED, so there is no need to check it.

Signed-off-by: Haifeng Xu <haifeng.xu@xxxxxxxxxx>
---
kernel/locking/rwsem.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c
index 2340b6d90ec6..7a4d8a9ebd9c 100644
--- a/kernel/locking/rwsem.c
+++ b/kernel/locking/rwsem.c
@@ -1005,8 +1005,7 @@ rwsem_down_read_slowpath(struct rw_semaphore *sem, long count, unsigned int stat
* waiter, don't attempt optimistic lock stealing if the lock is
* currently owned by readers.
*/
- if ((atomic_long_read(&sem->owner) & RWSEM_READER_OWNED) &&
- (rcnt > 1) && !(count & RWSEM_WRITER_LOCKED))
+ if ((atomic_long_read(&sem->owner) & RWSEM_READER_OWNED) && (rcnt > 1))
goto queue;

/*
--
2.25.1