From b76734e5e34e1889ab9fc5f3756570b1129f0f50 Mon Sep 17 00:00:00 2001
From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Date: Fri, 25 Jul 2008 01:47:16 -0700
Subject: [PATCH] memcg: add hints for branch

Showing brach direction for obvious conditions.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Cc: Paul Menage <menage@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 mm/memcontrol.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index f46b8615de6..04ded27f622 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -550,7 +550,7 @@ retry:
 	 * The page_cgroup exists and
 	 * the page has already been accounted.
 	 */
-	if (pc) {
+	if (unlikely(pc)) {
 		VM_BUG_ON(pc->page != page);
 		VM_BUG_ON(!pc->mem_cgroup);
 		unlock_page_cgroup(page);
@@ -559,7 +559,7 @@ retry:
 	unlock_page_cgroup(page);
 
 	pc = kmem_cache_alloc(page_cgroup_cache, gfp_mask);
-	if (pc == NULL)
+	if (unlikely(pc == NULL))
 		goto err;
 
 	/*
@@ -616,7 +616,7 @@ retry:
 		pc->flags = PAGE_CGROUP_FLAG_ACTIVE;
 
 	lock_page_cgroup(page);
-	if (page_get_page_cgroup(page)) {
+	if (unlikely(page_get_page_cgroup(page))) {
 		unlock_page_cgroup(page);
 		/*
 		 * Another charge has been added to this page already.
@@ -690,7 +690,7 @@ __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype)
 	 */
 	lock_page_cgroup(page);
 	pc = page_get_page_cgroup(page);
-	if (!pc)
+	if (unlikely(!pc))
 		goto unlock;
 
 	VM_BUG_ON(pc->page != page);
-- 
2.41.1