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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 C847CC433E0 for ; Tue, 26 May 2020 19:56:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A4733207D8 for ; Tue, 26 May 2020 19:56:38 +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="cHOx5G+k" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390056AbgEZT4h (ORCPT ); Tue, 26 May 2020 15:56:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41306 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389442AbgEZT4h (ORCPT ); Tue, 26 May 2020 15:56:37 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4B07BC03E96D for ; Tue, 26 May 2020 12:56:37 -0700 (PDT) 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; bh=l4mg12U4fZfWWKSxX7s1XyiI8EaUXhtofn/a97kc9q8=; b=cHOx5G+kPvNaBLGQnq5ltqXfmT uDI/en9u0J07hTA2Hcai4XZGAH2qTK4xBCgVqIy1mjt8CyOgUwBf6/gb/tmPXGUGE5cr24oei4bik TQ/Hai5meajkcUqqvWs+TgKxe6KFLzBdchy8wDNr2RX+h28PXTBzxGhjmww0lijnz97l/7THEl6W+ I6wPFq9S0ZVuy1/hicrYglAqKhrLrfWeYUYxRuvZgG27DAKqqkRv7FwzkbZ1NgCT5a+ust6haO0lO 9VWhM1DP+gbhKTY1BqnLk0aEezEpf4M5ChGdYB7+ykvsZXUw6TjOIzgqE9igmrrj2COPjf3t6tp8E NLPWUWeA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jdfge-0007NQ-3E; Tue, 26 May 2020 19:56:32 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 5C5F5300478; Tue, 26 May 2020 21:56:30 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 218E22BBAA8F8; Tue, 26 May 2020 21:56:30 +0200 (CEST) Date: Tue, 26 May 2020 21:56:30 +0200 From: Peter Zijlstra To: Qian Cai Cc: Waiman Long , Ingo Molnar , Will Deacon , linux-kernel@vger.kernel.org Subject: Re: [PATCH] locking/lockdep: Increase MAX_LOCKDEP_ENTRIES by half Message-ID: <20200526195630.GF325280@hirez.programming.kicks-ass.net> References: <20200526174349.8312-1-longman@redhat.com> <20200526185850.GE991@lca.pw> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200526185850.GE991@lca.pw> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 26, 2020 at 02:58:50PM -0400, Qian Cai wrote: > I still don't understand why reading all sysfs files on this system > could increase that much, but here is the lockdep file after > running sysfs read to see if you could spot anything obviously, > > https://cailca.github.io/files/lockdep.txt 00000000f011a2a5 OPS: 20 FD: 45 BD: 1 .+.+: kn->active#834 is that somewhere near the number of CPUs you have? Anyway, there's very long "kn->active#..." chains in there, which seems to suggest some annotation is all sorts of buggered.