From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx137.postini.com [74.125.245.137]) by kanga.kvack.org (Postfix) with SMTP id 19F1C6B009B for ; Tue, 20 Nov 2012 21:48:55 -0500 (EST) Received: by mail-pa0-f41.google.com with SMTP id bj3so678402pad.14 for ; Tue, 20 Nov 2012 18:48:54 -0800 (PST) Date: Tue, 20 Nov 2012 18:48:52 -0800 (PST) From: David Rientjes Subject: [patch] mm, memcg: avoid unnecessary function call when memcg is disabled fix In-Reply-To: <50AC282A.4070309@jp.fujitsu.com> Message-ID: References: <20121120134932.055bc192.akpm@linux-foundation.org> <50AC282A.4070309@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Kamezawa Hiroyuki , Andrew Morton Cc: Johannes Weiner , Michal Hocko , Hugh Dickins , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org Move the check for !mm out of line as suggested by Andrew. Signed-off-by: David Rientjes --- include/linux/memcontrol.h | 2 +- mm/memcontrol.c | 3 +++ 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -185,7 +185,7 @@ void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx); static inline void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx) { - if (mem_cgroup_disabled() || !mm) + if (mem_cgroup_disabled()) return; __mem_cgroup_count_vm_event(mm, idx); } diff --git a/mm/memcontrol.c b/mm/memcontrol.c --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1021,6 +1021,9 @@ void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx) { struct mem_cgroup *memcg; + if (!mm) + return; + rcu_read_lock(); memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); if (unlikely(!memcg)) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org