[PATCH v4 3/5] rwsem: remove try_reader_grant label do_wake

[Tim Chen]

That make code simple and more readable

Signed-off-by: Alex Shi <alex.shi@xxxxxxxxx>
---
 lib/rwsem.c |   12 +++++++-----
 1 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/lib/rwsem.c b/lib/rwsem.c
index 42f1b1a..a8055cf 100644
--- a/lib/rwsem.c
+++ b/lib/rwsem.c
@@ -85,15 +85,17 @@ __rwsem_do_wake(struct rw_semaphore *sem, enum rwsem_wake_type wake_type)
 	adjustment = 0;
 	if (wake_type != RWSEM_WAKE_READ_OWNED) {
 		adjustment = RWSEM_ACTIVE_READ_BIAS;
- try_reader_grant:
-		oldcount = rwsem_atomic_update(adjustment, sem) - adjustment;
-		if (unlikely(oldcount < RWSEM_WAITING_BIAS)) {
-			/* A writer stole the lock. Undo our reader grant. */
+		while (1) {
+			oldcount = rwsem_atomic_update(adjustment, sem)
+								- adjustment;
+			if (likely(oldcount >= RWSEM_WAITING_BIAS))
+				break;
+
+			 /* A writer stole the lock.  Undo our reader grant. */
 			if (rwsem_atomic_update(-adjustment, sem) &
 						RWSEM_ACTIVE_MASK)
 				return sem;
 			/* Last active locker left. Retry waking readers. */
-			goto try_reader_grant;
 		}
 	}
 
-- 
1.7.4.4



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