Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751854AbaBRT17 (ORCPT ); Tue, 18 Feb 2014 14:27:59 -0500 Received: from g2t1383g.austin.hp.com ([15.217.136.92]:54154 "EHLO g2t1383g.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750966AbaBRT15 (ORCPT ); Tue, 18 Feb 2014 14:27:57 -0500 Message-ID: <5303B422.2010304@hp.com> Date: Tue, 18 Feb 2014 14:27:30 -0500 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: "H. Peter Anvin" CC: Thomas Gleixner , Ingo Molnar , Arnd Bergmann , linux-arch@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, Peter Zijlstra , Steven Rostedt , Andrew Morton , Michel Lespinasse , Andi Kleen , Rik van Riel , "Paul E. McKenney" , Linus Torvalds , Raghavendra K T , George Spelvin , Tim Chen , Daniel J Blueman , Alexander Fyodorov , Aswin Chandramouleeswaran , Scott J Norton , Thavatchai Makphaibulchoke Subject: Re: [PATCH v4 0/3] qspinlock: Introducing a 4-byte queue spinlock References: <1392669684-4807-1-git-send-email-Waiman.Long@hp.com> <53029167.4060109@zytor.com> In-Reply-To: <53029167.4060109@zytor.com> 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 On 02/17/2014 05:47 PM, H. Peter Anvin wrote: > On 02/17/2014 12:41 PM, Waiman Long wrote: >> v3->v4: >> - Remove debugging code and fix a configuration error >> - Simplify the qspinlock structure and streamline the code to make it >> perform a bit better >> - Add an x86 version of asm/qspinlock.h for holding x86 specific >> optimization. >> - Add an optimized x86 code path for 2 contending tasks to improve >> low contention performance. >> >> v2->v3: >> - Simplify the code by using numerous mode only without an unfair option. >> - Use the latest smp_load_acquire()/smp_store_release() barriers. >> - Move the queue spinlock code to kernel/locking. >> - Make the use of queue spinlock the default for x86-64 without user >> configuration. >> - Additional performance tuning. >> >> v1->v2: >> - Add some more comments to document what the code does. >> - Add a numerous CPU mode to support>= 16K CPUs >> - Add a configuration option to allow lock stealing which can further >> improve performance in many cases. >> - Enable wakeup of queue head CPU at unlock time for non-numerous >> CPU mode. >> >> This patch set introduces a queue-based spinlock implementation that >> can replace the default ticket spinlock without increasing the size >> of the spinlock data structure. As a result, critical kernel data >> structures that embed spinlock won't increase in size and breaking >> data alignments. >> > This is starting to look good, so I have pulled it into > tip:x86/spinlocks to start give it some testing mileage. > > -hpa > > Thank for the additional testing. Please let me know if you find anything wrong. -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/