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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 91F15C433E1 for ; Sat, 23 May 2020 00:12:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6949C20757 for ; Sat, 23 May 2020 00:12:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590192745; bh=i2mVo27EQF4lNBS9IayQbm5SwyNaYxnGrl/yPkcM4iY=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:List-ID: From; b=ukIvetRwX8KQWLnxkDsDMRQmMJrqmCSoLU958a0lbvur2Qc00iApexOonjILBfK34 aSHThZtB+mtWXzMX91eHyiPFjZovd4vtG2RC1TAowARA19DzCstmqPgW9WNgq1bgVp Oum/nrffvTTPxYG7NptrJns+faaNc5PBXMI/Tu2E= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387435AbgEWAMZ (ORCPT ); Fri, 22 May 2020 20:12:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:36598 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731169AbgEWAMY (ORCPT ); Fri, 22 May 2020 20:12:24 -0400 Received: from paulmck-ThinkPad-P72.home (50-39-105-78.bvtn.or.frontiernet.net [50.39.105.78]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id EFBD2206B6; Sat, 23 May 2020 00:12:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590192744; bh=i2mVo27EQF4lNBS9IayQbm5SwyNaYxnGrl/yPkcM4iY=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=nTcstaV27D3miCiaUjMLPYQNjsOV2zjv9IVJEjCxOvFHc+7X0m5O7zN8t8W+JIABN B8SaMwegapCgvtM+btv3jc9iY4SqC5Lp51+XjWN9/vbN62LJbOIfl0U+hl9gIaSr+O 3a7KjDpOAIVOYbjPt5t/Sk3o8W2OTu+t9w4y2njw= Received: by paulmck-ThinkPad-P72.home (Postfix, from userid 1000) id D57973521294; Fri, 22 May 2020 17:12:23 -0700 (PDT) Date: Fri, 22 May 2020 17:12:23 -0700 From: "Paul E. McKenney" To: Stephen Rothwell Cc: Will Deacon , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Peter Zijlstra , Linux Next Mailing List , Linux Kernel Mailing List , elver@google.com, bp@alien8.de Subject: Re: linux-next: build failure after merge of the tip tree Message-ID: <20200523001223.GA23921@paulmck-ThinkPad-P72> Reply-To: paulmck@kernel.org References: <20200522033119.1bbd99c5@canb.auug.org.au> <20200521173520.GL6608@willie-the-truck> <20200522171708.5f392fde@canb.auug.org.au> <20200522174944.1a1732fa@canb.auug.org.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200522174944.1a1732fa@canb.auug.org.au> 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 On Fri, May 22, 2020 at 05:49:44PM +1000, Stephen Rothwell wrote: > Hi all, > > On Fri, 22 May 2020 17:17:08 +1000 Stephen Rothwell wrote: > > > > On Thu, 21 May 2020 18:35:22 +0100 Will Deacon wrote: > > > > > > [+Marco and Boris] > > > > > > On Fri, May 22, 2020 at 03:31:19AM +1000, Stephen Rothwell wrote: > > > > After merging the tip tree, all my linux-next builds took signficantly > > > > longer and used much more memory. In some cases, builds would seg fault > > > > due to running out of memory :-( > > > > > > > > I have eventaully bisected it to commit > > > > > > > > cdd28ad2d811 ("READ_ONCE: Use data_race() to avoid KCSAN instrumentation") > > > > > > > > For my (e.g.) x86_64 allmodconfig builds (cross compiled on PowerPC le, > > > > -j80) the elapsed time went from around 9 minutes to over 17 minutes > > > > and the maximum resident size (as reported by /usr/bin/time) from around > > > > 500M to around 2G (I saw lots of cc1 processes over 2G in size). > > > > > > > > For tomorrow's linux-next (well, later today :-() I will revert that > > > > commit (and its child) when I merge the tip tree. > > > > > > Sorry about that, seems we can't avoid running into compiler problems with > > > this lot. The good news is that there's a series to fix this here: > > > > > > https://lore.kernel.org/r/20200521142047.169334-1-elver@google.com > > > > > > so hopefully this be fixed in -tip soon (but I agree that reverting the > > > thing in -next in the meantime makes sense). > > > > Unfortunately, the revert didn't work, so instead I have used the tip > > tree from next-20200518 for today (hopefully this will all be sorted > > out by Monday). > > And the rcu tree has merged part of the tip tree that contains the > offending commits, so I have used the version fo the rcu tree from > next-20200519 for today. Please accept my apologies for my part of this problem! I don't see the slowdowns on my normal test system (possibly due to gcc 4.8.5), but I do see them on my laptop. Marco, Thomas, is there any better setup I can provide Stephen? Or is the next-20200519 -rcu tree the best we have right now? Thanx, Paul