From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932934AbcFOUE2 (ORCPT ); Wed, 15 Jun 2016 16:04:28 -0400 Received: from mail-bn1bon0115.outbound.protection.outlook.com ([157.56.111.115]:5792 "EHLO na01-bn1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932084AbcFOUEW (ORCPT ); Wed, 15 Jun 2016 16:04:22 -0400 Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=waiman.long@hpe.com; Message-ID: <5761B4B7.3070102@hpe.com> Date: Wed, 15 Jun 2016 16:04:07 -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: Davidlohr Bueso , Ingo Molnar , , , , , , , Jason Low , Dave Chinner , Scott J Norton , Douglas Hatch Subject: Re: [RFC PATCH-tip v2 1/6] locking/osq: Make lock/unlock proper acquire/release barrier References: <1465944489-43440-1-git-send-email-Waiman.Long@hpe.com> <1465944489-43440-2-git-send-email-Waiman.Long@hpe.com> <20160615165659.GC2094@linux-80c1.suse> <20160615171250.GO30921@twins.programming.kicks-ass.net> <5761A7C0.6000709@hpe.com> In-Reply-To: <5761A7C0.6000709@hpe.com> Content-Type: text/plain; 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If we bail because >> need_resched() we don't need the acquire I think. > > Yes, I only need the acquire barrier when the locking is successful. > Thanks for the suggestion. I will make the change accordingly. > BTW, when will the smp_acquire__after_ctrl_dep() patch goes into the tip tree? My patch will have a dependency on that when I make the change. Cheers, Longman