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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 A6744C43143 for ; Tue, 2 Oct 2018 14:28:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5918B2083F for ; Tue, 2 Oct 2018 14:28:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="gUd5ufkG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5918B2083F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.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 S1727653AbeJBVLw (ORCPT ); Tue, 2 Oct 2018 17:11:52 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:39754 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726118AbeJBVLw (ORCPT ); Tue, 2 Oct 2018 17:11:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=4AMiJ06wJT0aqlGZntN890lxEZFNTF2KcatGwH9hxoQ=; b=gUd5ufkG/ByagFRv4cmkUZHLK tA5hHMHc7zjG862BsGSbL0hoHxGmWhzheJimSK+4wfLbs/lD7Zmpc/K3uEriB0rL5IIeR3910xz3v NWUv+kyvuQFRoDniev8YfhSYPTgl2jlE2F4hBeJqetiqWHIzr7gibXnudWsyVBTphMLF4jjUdxyl1 1giBd0M4hODoBNrpR41erbfSm7BChWX/gYjtZipOvsjVQK13c1hxJzi6z77zXUwhI21x/6rbVrnXI Db0WG0+JU8+sm/rbcNVEKLk//WpzZSBXQwagvdm5GkL4H+Ge8v9ExVpZf6RwhuOh6WJCMYBp/A7DQ sa0qHiE6A==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1g7Lel-00012s-7y; Tue, 02 Oct 2018 14:28:11 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id B1E18202B9CBE; Tue, 2 Oct 2018 16:28:09 +0200 (CEST) Date: Tue, 2 Oct 2018 16:28:09 +0200 From: Peter Zijlstra To: Waiman Long Cc: Ingo Molnar , Ingo Molnar , Will Deacon , linux-kernel@vger.kernel.org Subject: Re: [PATCH 4/5] locking/lockdep: Make class->ops a percpu counter Message-ID: <20181002142809.GH26858@hirez.programming.kicks-ass.net> 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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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.