From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH] cgroup: remove redundate get/put of old css_set from migrate Date: Mon, 19 Dec 2011 09:16:33 -0800 Message-ID: <20111219171633.GI24519@google.com> References: <1324053511-24591-1-git-send-email-msb@chromium.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; bh=TfrjqTYeZiph6Q9V3anuxiVntS/GkIjn2p8AWBYhbu0=; b=pmlqP9vFH4r/k5MjT+O7sRXWDi9dnDJfg/g5+D+YuSu1BRdN/soYYzO0Ox0EoE0NVy 60F07m7Jm41IgPP0cDGwtcfjhvCPE/CosHPiMsWiP8cRryUTjy6Sf0EA3uXJ4FbIfD4v pgfEywa59uDT/rYyJUWDkUdI/Wk3Eb03yam70= Content-Disposition: inline In-Reply-To: <1324053511-24591-1-git-send-email-msb-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Mandeep Singh Baines Cc: Frederic Weisbecker , containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Oleg Nesterov , cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Andrew Morton , Paul Menage On Fri, Dec 16, 2011 at 08:38:31AM -0800, Mandeep Singh Baines wrote: > We can now assume that the css_set reference held by the task > will not go away for an exiting task. PF_EXITING state can be > trusted throughout migration by checking it after locking > threadgroup. > > This patch depends on: > > commit cd3d095275374220921fcf0d4e0c16584b26ddbc > Author: Tejun Heo > Date: Mon Dec 12 18:12:21 2011 -0800 > > cgroup: always lock threadgroup during migration > > Signed-off-by: Mandeep Singh Baines > Cc: Tejun Heo > Cc: Li Zefan > Cc: containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org > Cc: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > Cc: KAMEZAWA Hiroyuki > Cc: Frederic Weisbecker > Cc: Oleg Nesterov > Cc: Andrew Morton > Cc: Paul Menage Li, can you please ack this? Thanks. -- tejun From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752559Ab1LSRQk (ORCPT ); Mon, 19 Dec 2011 12:16:40 -0500 Received: from mail-gy0-f174.google.com ([209.85.160.174]:46243 "EHLO mail-gy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752307Ab1LSRQi (ORCPT ); Mon, 19 Dec 2011 12:16:38 -0500 Date: Mon, 19 Dec 2011 09:16:33 -0800 From: Tejun Heo To: Mandeep Singh Baines Cc: Li Zefan , linux-kernel@vger.kernel.org, containers@lists.linux-foundation.org, cgroups@vger.kernel.org, KAMEZAWA Hiroyuki , Frederic Weisbecker , Oleg Nesterov , Andrew Morton , Paul Menage Subject: Re: [PATCH] cgroup: remove redundate get/put of old css_set from migrate Message-ID: <20111219171633.GI24519@google.com> References: <1324053511-24591-1-git-send-email-msb@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1324053511-24591-1-git-send-email-msb@chromium.org> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 16, 2011 at 08:38:31AM -0800, Mandeep Singh Baines wrote: > We can now assume that the css_set reference held by the task > will not go away for an exiting task. PF_EXITING state can be > trusted throughout migration by checking it after locking > threadgroup. > > This patch depends on: > > commit cd3d095275374220921fcf0d4e0c16584b26ddbc > Author: Tejun Heo > Date: Mon Dec 12 18:12:21 2011 -0800 > > cgroup: always lock threadgroup during migration > > Signed-off-by: Mandeep Singh Baines > Cc: Tejun Heo > Cc: Li Zefan > Cc: containers@lists.linux-foundation.org > Cc: cgroups@vger.kernel.org > Cc: KAMEZAWA Hiroyuki > Cc: Frederic Weisbecker > Cc: Oleg Nesterov > Cc: Andrew Morton > Cc: Paul Menage Li, can you please ack this? Thanks. -- tejun