From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D933EC64EBC for ; Thu, 4 Oct 2018 13:05:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 97E2E2084D for ; Thu, 4 Oct 2018 13:05:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 97E2E2084D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727479AbeJDT6d (ORCPT ); Thu, 4 Oct 2018 15:58:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35146 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727336AbeJDT6c (ORCPT ); Thu, 4 Oct 2018 15:58:32 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C89B180F8F; Thu, 4 Oct 2018 13:05:20 +0000 (UTC) Received: from llong.remote.csb (dhcp-17-55.bos.redhat.com [10.18.17.55]) by smtp.corp.redhat.com (Postfix) with ESMTP id D15D117CFA; Thu, 4 Oct 2018 13:05:19 +0000 (UTC) Subject: Re: [PATCH v2 4/5] locking/lockdep: Make class->ops a percpu counter To: Ingo Molnar Cc: Peter Zijlstra , Ingo Molnar , Will Deacon , linux-kernel@vger.kernel.org References: <1538511560-10090-1-git-send-email-longman@redhat.com> <1538511560-10090-5-git-send-email-longman@redhat.com> <20181003074809.GJ26858@hirez.programming.kicks-ass.net> <62801eb9-16f2-606f-d3a2-61fef5b0a704@redhat.com> <20181004101423.GA83274@gmail.com> From: Waiman Long Organization: Red Hat Message-ID: Date: Thu, 4 Oct 2018 09:05:19 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.0 MIME-Version: 1.0 In-Reply-To: <20181004101423.GA83274@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Thu, 04 Oct 2018 13:05:20 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/04/2018 06:14 AM, Ingo Molnar wrote: > * Waiman Long wrote: > >> diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h >> index b0d0b51c4d85..1fd82ff99c65 100644 >> --- a/include/linux/lockdep.h >> +++ b/include/linux/lockdep.h >> @@ -99,13 +99,8 @@ struct lock_class { >> */ >> unsigned int version; >> >> - /* >> - * Statistics counter: >> - */ >> - unsigned long ops; >> - >> - const char *name; >> int name_version; >> + const char *name; > 'name' gets moved by the patch - better structure packing on 64-bit kernels? > > Looks good to me otherwise. > > Thanks, > > Ingo Yes, that is done on purpose to pack the 2 integers together to remove two 4-byte holes on 64-bit archs. Cheers, Longman