From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754999AbbERUHF (ORCPT ); Mon, 18 May 2015 16:07:05 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:34080 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754506AbbERUHB (ORCPT ); Mon, 18 May 2015 16:07:01 -0400 Date: Mon, 18 May 2015 22:06:55 +0200 From: Peter Zijlstra To: Tejun Heo Cc: lizefan@huawei.com, cgroups@vger.kernel.org, mingo@redhat.com, linux-kernel@vger.kernel.org Subject: Re: [PATCHSET] cgroup, sched: restructure threadgroup locking and replace it with a percpu_rwsem Message-ID: <20150518200655.GB19282@twins.programming.kicks-ass.net> References: <1431549318-16756-1-git-send-email-tj@kernel.org> <20150518163440.GA24861@htj.duckdns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150518163440.GA24861@htj.duckdns.org> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 18, 2015 at 12:34:40PM -0400, Tejun Heo wrote: > On Wed, May 13, 2015 at 04:35:15PM -0400, Tejun Heo wrote: > > threadgroup locking was added because cgroup needs threadgroups to > > stay stable across attach operations. It was implemented as a > > per-signal_struct generic locking mechanism so that other users which > > require threadgroups stable across blocking operations can use it too; > > however, it hasn't grown any other use cases and still conditionalized > > on CONFIG_CGROUPS. > > Ingo, Peter, what do you guys think? I had a brief look and didn't spot anhything really weird. I'll try and give is a little more time tomorrow. On routing I think you can take it through the cgroup tree if Ingo is ok with that.