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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 77BC3C433E6 for ; Mon, 1 Mar 2021 15:47:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3E03464DF5 for ; Mon, 1 Mar 2021 15:47:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237383AbhCAPrB (ORCPT ); Mon, 1 Mar 2021 10:47:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55962 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236819AbhCAPq4 (ORCPT ); Mon, 1 Mar 2021 10:46:56 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4AFC4C061756; Mon, 1 Mar 2021 07:46:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.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=fGQP+mV2y92qkbpjMBXPSQ03FtN3LiZq6yfm+Qczok4=; b=eINfi8rePq0BOqcbnRkDRGaTUU j/qrilFBjLOCeVw+dDK6ymE27NlfTD4qj5PiC9OpEr92WRQhvK5mhl7EptC4VPBADqYyJ1mXMTKWZ uD7r9jykhVFHBsqVynWGVz581McsTNLQ+uvh9G6q5zpYKTulcgADr2pUFmQpLcVHECdoVk7fVZKDq abk3z4yLDVmB5v1h+3UvRwB/nnF/QT3CirQbrsTFT5WpID+C1WeE6KYyEbWFpdyvIAdJjCTxvqFCH H4ASfBxiccWVlcOowbbH4SA0XB89kiH0ckEJtrbNWWglMNnrcCMPhVHWdrVW5ByJo4+gjFEIZcCe2 qjFREMYg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1lGkjs-00FuI6-5F; Mon, 01 Mar 2021 15:45:49 +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 B8346301959; Mon, 1 Mar 2021 16:45:39 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id A9A3620C80E0E; Mon, 1 Mar 2021 16:45:39 +0100 (CET) Date: Mon, 1 Mar 2021 16:45:39 +0100 From: Peter Zijlstra To: "Paul E. McKenney" Cc: Juergen Gross , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, mhocko@suse.com, Jonathan Corbet Subject: Re: [PATCH 3/3] kernel/smp: add more data to CSD lock debugging Message-ID: References: <20210226112521.8641-1-jgross@suse.com> <20210226112521.8641-4-jgross@suse.com> <20210226181205.GZ2743@paulmck-ThinkPad-P72> <20210301000704.GF2696@paulmck-ThinkPad-P72> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210301000704.GF2696@paulmck-ThinkPad-P72> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Feb 28, 2021 at 04:07:04PM -0800, Paul E. McKenney wrote: > On Fri, Feb 26, 2021 at 10:05:51PM +0100, Peter Zijlstra wrote: > > On Fri, Feb 26, 2021 at 10:12:05AM -0800, Paul E. McKenney wrote: > > > On Fri, Feb 26, 2021 at 05:38:44PM +0100, Peter Zijlstra wrote: > > > > > > > > I hate all of this, but if this will finally catch the actual problem, > > > > we can then revert all this, so sure. > > > > > > OK, I will bite... What exactly do you hate about it? > > > > It's ugly and messy. We're basically commiting a debug session. Normally > > gunk like this is done in private trees, then we find the problem and > > fix that and crap like this never sees the light of day. > > Is your hatred due to the presence of debug code at all, or a belief that > this code is unlikely to be useful in any subsequent IPI-related bug hunt? The clutter, mostly I think. There's a lot of debug sprinkled about.