locking/atomic, arch/rwsem: Employ atomic_long_fetch_add()

Now that we have fetch_add() we can stop using add_return() - val.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jason Low <jason.low2@hpe.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <waiman.long@hpe.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Peter Zijlstra 2016-05-18 12:42:21 +02:00 committed by Ingo Molnar
parent f9852b74be
commit 86a3b5f34f

View file

@ -153,7 +153,7 @@ __rwsem_mark_wake(struct rw_semaphore *sem,
if (wake_type != RWSEM_WAKE_READ_OWNED) {
adjustment = RWSEM_ACTIVE_READ_BIAS;
try_reader_grant:
oldcount = atomic_long_add_return(adjustment, &sem->count) - adjustment;
oldcount = atomic_long_fetch_add(adjustment, &sem->count);
if (unlikely(oldcount < RWSEM_WAITING_BIAS)) {
/*