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=0.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, FSL_HELO_FAKE,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=no 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 7FBB5C43143 for ; Tue, 2 Oct 2018 18:54:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 62B4120666 for ; Tue, 2 Oct 2018 18:54:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ZQUxJMw3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 62B4120666 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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 S1727469AbeJCBip (ORCPT ); Tue, 2 Oct 2018 21:38:45 -0400 Received: from mail-wm1-f66.google.com ([209.85.128.66]:36331 "EHLO mail-wm1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726293AbeJCBio (ORCPT ); Tue, 2 Oct 2018 21:38:44 -0400 Received: by mail-wm1-f66.google.com with SMTP id n23-v6so3223695wmc.1 for ; Tue, 02 Oct 2018 11:53:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=7OX2FKpRpwJ5//TX7qQawxC9lPW5jvwnOTTCtKw9BYk=; b=ZQUxJMw30aQKshkVjkHWJd0DUuSTSITo6Vwy5kr6RxfiM9I2a7spvxL32x0TNuKfgC NMfgQNjeDELFjZ8DEItvtyM0NOkMTnjpNlkA208y0tPlvr/faRmjEBjngiuWOC2grgC4 AYB6XTq0GsXNtzMS4EW7iNScKiE7fGMK6VMf6kwgmtJ8jqaDY48fNUzpyHNAZ6haP/Jr k/I61jLHptpIPgUbgYBZQ8S1q47XiORxC4SIx0iyzlJJ0ihkBmfeCOZsaT9/Ig1SzaiW gMsk33sv1EsLEJxVkX1h2ALlMsPckiCFPe8YCSX+/r8p+NV4qIURWGHRGhwKNsfd76c9 izAQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=7OX2FKpRpwJ5//TX7qQawxC9lPW5jvwnOTTCtKw9BYk=; b=DPC4NxmPzCdqxemO6t7e725RhkxsyKWLeu/P+2f7rz2G+/mw0cKWjjKQuF2PBkGt+h P0sSQeZIbYuBXy7o05Be8vka2GDEOKZr6ZEFHaLwCD70fq+GMGuA1I0JGejpdSVs8GFH PtJ2sHS7/ZKMFRWewme2D8maXZwmskTjOOcmvPvFabP5Uh1lw7e7hkGbDlDGILgiT1Ak O8Ui97mRVE68fhdjwNKNmkYc+JZHsxfl9cJh1tg6yWg3kSpm0VD4clCnvVwXlLo0uCy7 IIpaKadbhEuWAuAj5iNU/1x4dU6QWOHvZim1/53YYD616Q6g9m4+5ncPzb6OEU8Up562 F92A== X-Gm-Message-State: ABuFfoi2ViJb9iuZj7mf+1vgzbJhIltZjzqUGjLZmiLKo3ZRdoi+PN1G 9m+PDWXo3yUDlv0UwvxP0rU= X-Google-Smtp-Source: ACcGV60Oi1GgjZkpLPT01iFneCuNAwHuUbq6V4ERXtIK7kaRm+dyaaDMPhT1nKYToxwtfznKJDEVEA== X-Received: by 2002:a1c:2681:: with SMTP id m123-v6mr2573541wmm.129.1538506436369; Tue, 02 Oct 2018 11:53:56 -0700 (PDT) Received: from gmail.com (2E8B0CD5.catv.pool.telekom.hu. [46.139.12.213]) by smtp.gmail.com with ESMTPSA id 185-v6sm16842961wmy.38.2018.10.02.11.53.55 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 02 Oct 2018 11:53:55 -0700 (PDT) Date: Tue, 2 Oct 2018 20:53:53 +0200 From: Ingo Molnar To: Peter Zijlstra Cc: Waiman Long , Ingo Molnar , Will Deacon , linux-kernel@vger.kernel.org, Thomas Gleixner Subject: Re: [PATCH 4/5] locking/lockdep: Make class->ops a percpu counter Message-ID: <20181002185353.GA36596@gmail.com> References: <1538157201-29173-1-git-send-email-longman@redhat.com> <1538157201-29173-5-git-send-email-longman@redhat.com> <20181002093907.GV3439@hirez.programming.kicks-ass.net> <20181002095543.GA55344@gmail.com> <20181002142809.GH26858@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181002142809.GH26858@hirez.programming.kicks-ass.net> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Peter Zijlstra wrote: > On Tue, Oct 02, 2018 at 10:10:48AM -0400, Waiman Long wrote: > > One alternative is to group it under CONFIG_DEBUG_LOCKDEP again. This > > metric was originally under CONFIG_DEBUG_LOCKDEP, but was moved to > > CONFIG_LOCKDEP when trying to make other lock debugging statistics > > per-cpu counters. It was probably because this metric is per lock class > > while the rests are global. > > > > By doing so, you incur the memory cost only when CONFIG_DEBUG_LOCKDEP is > > defined. > > > > What do you think? > > Works for me. Sounds good to me too! Thanks, Ingo