Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753197AbbGNSsA (ORCPT ); Tue, 14 Jul 2015 14:48:00 -0400 Received: from g4t3427.houston.hp.com ([15.201.208.55]:46033 "EHLO g4t3427.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752989AbbGNSr6 (ORCPT ); Tue, 14 Jul 2015 14:47:58 -0400 Message-ID: <55A5595C.80403@hp.com> Date: Tue, 14 Jul 2015 14:47:56 -0400 From: Waiman Long User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.12) Gecko/20130109 Thunderbird/10.0.12 MIME-Version: 1.0 To: Peter Zijlstra CC: Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , x86@kernel.org, linux-kernel@vger.kernel.org, Scott J Norton , Douglas Hatch Subject: Re: [PATCH 5/7] locking/pvqspinlock: Add pending bit support References: <1436647018-49734-1-git-send-email-Waiman.Long@hp.com> <1436647018-49734-6-git-send-email-Waiman.Long@hp.com> <20150712082158.GR19282@twins.programming.kicks-ass.net> In-Reply-To: <20150712082158.GR19282@twins.programming.kicks-ass.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 974 Lines: 22 On 07/12/2015 04:21 AM, Peter Zijlstra wrote: > On Sat, Jul 11, 2015 at 04:36:56PM -0400, Waiman Long wrote: >> Like the native qspinlock, using the pending bit when it is lightly >> loaded to acquire the lock is faster than going through the PV queuing >> process which is even slower than the native queuing process. It also >> avoids loading two additional cachelines (the MCS and PV nodes). >> >> This patch adds the pending bit support for PV qspinlock. The >> pending bit code has a smaller spin threshold. It will default back >> to the queuing method if it cannot acquired the lock within a certain >> time limit. > -ENONUMBERS Will send out an updated patchset with patch-to-patch performance numbers. Cheers, Longman -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/