From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752178AbaBGREm (ORCPT ); Fri, 7 Feb 2014 12:04:42 -0500 Received: from zene.cmpxchg.org ([85.214.230.12]:58561 "EHLO zene.cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750993AbaBGREj (ORCPT ); Fri, 7 Feb 2014 12:04:39 -0500 From: Johannes Weiner To: Michal Hocko Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [patch 5/8] memcg: remove unnecessary !mm check from try_get_mem_cgroup_from_mm() Date: Fri, 7 Feb 2014 12:04:22 -0500 Message-Id: <1391792665-21678-6-git-send-email-hannes@cmpxchg.org> X-Mailer: git-send-email 1.8.5.3 In-Reply-To: <1391792665-21678-1-git-send-email-hannes@cmpxchg.org> References: <1391792665-21678-1-git-send-email-hannes@cmpxchg.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Users pass either a mm that has been established under task lock, or use a verified current->mm, which means the task can't be exiting. Signed-off-by: Johannes Weiner --- mm/memcontrol.c | 7 ------- 1 file changed, 7 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index e1d7f33227e4..689fffdee471 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1075,13 +1075,6 @@ struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm) { struct mem_cgroup *memcg = NULL; - if (!mm) - return NULL; - /* - * Because we have no locks, mm->owner's may be being moved to other - * cgroup. We use css_tryget() here even if this looks - * pessimistic (rather than adding locks here). - */ rcu_read_lock(); do { memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); -- 1.8.5.3