From: Ondřej Surý <ondrej@sury.org>
Date: Thu, 23 Aug 2018 13:30:06 +0000 (+0200)
Subject: Directly use return value of atomic_compare_exchange_strong_explicit insteaf of compa... 
X-Git-Tag: v9.13.3~28^2~3
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9d5df99a9d9d13c9487969b6fa3818a8b83b4ee2;p=thirdparty%2Fbind9.git

Directly use return value of atomic_compare_exchange_strong_explicit insteaf of comparing expected value
---

diff --git a/lib/isc/rwlock.c b/lib/isc/rwlock.c
index b3151465a15..622cd7d2762 100644
--- a/lib/isc/rwlock.c
+++ b/lib/isc/rwlock.c
@@ -308,13 +308,13 @@ isc__rwlock_lock(isc_rwlock_t *rwl, isc_rwlocktype_t type) {
 		}
 
 		while (1) {
-			int_fast32_t cntflag2 = 0;
-			atomic_compare_exchange_strong_explicit
-				(&rwl->cnt_and_flag, &cntflag2, WRITER_ACTIVE,
-				 memory_order_relaxed, memory_order_relaxed);
-
-			if (cntflag2 == 0)
+			int_fast32_t zero = 0;
+			if (atomic_compare_exchange_strong_explicit
+			    (&rwl->cnt_and_flag, &zero, WRITER_ACTIVE,
+			     memory_order_relaxed, memory_order_relaxed))
+			{
 				break;
+			}
 
 			/* Another active reader or writer is working. */
 			LOCK(&rwl->lock);
@@ -409,7 +409,9 @@ isc_rwlock_trylock(isc_rwlock_t *rwl, isc_rwlocktype_t type) {
 		if (!atomic_compare_exchange_strong_explicit
 		    (&rwl->cnt_and_flag, &zero, WRITER_ACTIVE,
 		     memory_order_relaxed, memory_order_relaxed))
+		{
 			return (ISC_R_LOCKBUSY);
+		}
 
 		/*
 		 * XXXJT: jump into the queue, possibly breaking the writer