From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754610AbbKXOuu (ORCPT ); Tue, 24 Nov 2015 09:50:50 -0500 Received: from mail-yk0-f180.google.com ([209.85.160.180]:32927 "EHLO mail-yk0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754586AbbKXOur (ORCPT ); Tue, 24 Nov 2015 09:50:47 -0500 Date: Tue, 24 Nov 2015 09:50:43 -0500 From: Tejun Heo To: Peter Zijlstra Cc: Oleg Nesterov , Ingo Molnar , Rik van Riel , Thomas Gleixner , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 1/1] stop_machine: Remove stop_cpus_lock and lg_double_lock/unlock() Message-ID: <20151124145043.GD17033@mtj.duckdns.org> References: <20151121181129.GA425@redhat.com> <20151121181148.GA433@redhat.com> <20151123215339.GF19072@mtj.duckdns.org> <20151124095156.GP17308@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151124095156.GP17308@twins.programming.kicks-ass.net> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Tue, Nov 24, 2015 at 10:51:56AM +0100, Peter Zijlstra wrote: > On Mon, Nov 23, 2015 at 04:53:39PM -0500, Tejun Heo wrote: > > > > Isn't this a lot more subtler than the other direction? Unless > > there's a clear performance advantage to removing stopper->lock, using > > lglock for both stop_two and stop_machine seems like an > > easier-to-follow approach to me. > > The idea is to kill lglock. There's only two users, this and fs/locks.c > for which I have patches -- which are being benchmarked 'now-ish' :-) Ah, I see. Please disregard my comment. The patch looks good to me. Please feel free to add Acked-by: Tejun Heo Thanks. -- tejun