Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754325Ab2KUCs4 (ORCPT ); Tue, 20 Nov 2012 21:48:56 -0500 Received: from mail-da0-f46.google.com ([209.85.210.46]:64611 "EHLO mail-da0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752304Ab2KUCsy (ORCPT ); Tue, 20 Nov 2012 21:48:54 -0500 Date: Tue, 20 Nov 2012 18:48:52 -0800 (PST) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com 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 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> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1300 Lines: 38 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 from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/