Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751885AbbFPBAc (ORCPT ); Mon, 15 Jun 2015 21:00:32 -0400 Received: from mail-ig0-f169.google.com ([209.85.213.169]:33619 "EHLO mail-ig0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750857AbbFPBAY (ORCPT ); Mon, 15 Jun 2015 21:00:24 -0400 MIME-Version: 1.0 In-Reply-To: <1434397028.1903.12.camel@stgolabs.net> References: <1432056298-18738-1-git-send-email-dave@stgolabs.net> <1432056298-18738-3-git-send-email-dave@stgolabs.net> <1433604461.3165.21.camel@stgolabs.net> <1434397028.1903.12.camel@stgolabs.net> Date: Mon, 15 Jun 2015 18:00:23 -0700 X-Google-Sender-Auth: T2eUH5emLiKDjQexZ4C6A3iOqWY Message-ID: Subject: Re: [PATCH 2/4] locking/rtmutex: Use cmp-cmpxchg From: Jason Low To: Davidlohr Bueso Cc: Jason Low , Thomas Gleixner , Peter Zijlstra , Ingo Molnar , Steven Rostedt , Mike Galbraith , "Paul E. McKenney" , Sebastian Andrzej Siewior , Linux Kernel Mailing List Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 796 Lines: 18 On Mon, Jun 15, 2015 at 12:37 PM, Davidlohr Bueso wrote: > On Mon, 2015-06-15 at 11:34 -0700, Jason Low wrote: >> The CCAS technique was typically used in the slow paths for those >> other locks, where the chance of the operation returning false is >> higher. > > That is true. Although I really want to use it in patch 4, I guess I > could move the check in there, and thus avoid having it in the fastpath. I agree, that way, we only have the extra check in cases where it is beneficial, like in the optimistic spin loop. Jason -- 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/