From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933120AbYDWDGF (ORCPT ); Tue, 22 Apr 2008 23:06:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756601AbYDWDFy (ORCPT ); Tue, 22 Apr 2008 23:05:54 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:59061 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1755169AbYDWDFx (ORCPT ); Tue, 22 Apr 2008 23:05:53 -0400 Message-ID: <480EA744.2050300@cn.fujitsu.com> Date: Wed, 23 Apr 2008 11:04:36 +0800 From: Li Zefan User-Agent: Thunderbird 2.0.0.9 (X11/20071115) MIME-Version: 1.0 To: Andrew Morton CC: Paul Menage , LKML , Linux Containers Subject: [PATCH] cgroup: use read lock to guard find_existing_css_set() Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The function does not modify anything (except the temporary css template), so it's sufficient to hold read lock. Signed-off-by: Li Zefan --- kernel/cgroup.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 2727f92..e9eb5da 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -406,11 +406,11 @@ static struct css_set *find_css_set( /* First see if we already have a cgroup group that matches * the desired set */ - write_lock(&css_set_lock); + read_lock(&css_set_lock); res = find_existing_css_set(oldcg, cgrp, template); if (res) get_css_set(res); - write_unlock(&css_set_lock); + read_unlock(&css_set_lock); if (res) return res; -- 1.5.4.rc3