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=-13.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 8FD87C388F9 for ; Tue, 3 Nov 2020 15:18:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 432C920757 for ; Tue, 3 Nov 2020 15:18:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604416689; bh=4+NbJFTPXLn00+roYDaxMSNvwFacHhij1ifzJGHsc3o=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:List-ID: From; b=rQhvvKuFCmuWr7X9lmk0ULTpY11gOS69qE9H+cnEu0eisYyPk/EqsdacBA5Ko4y+J B3q0zil0wapHjUxAGd4lreoG/hdS6IjNEpGfC/SREj9xNK/sTbf6nwT/8ebCmFDcSN zMkZnWzCQFpeFxXIwHAlclAqlPyP1vSCM96YkomA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728576AbgKCPSI (ORCPT ); Tue, 3 Nov 2020 10:18:08 -0500 Received: from mail.kernel.org ([198.145.29.99]:59144 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728536AbgKCPSE (ORCPT ); Tue, 3 Nov 2020 10:18:04 -0500 Received: from paulmck-ThinkPad-P72.home (50-39-104-11.bvtn.or.frontiernet.net [50.39.104.11]) (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 6984B20735; Tue, 3 Nov 2020 15:18:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604416683; bh=4+NbJFTPXLn00+roYDaxMSNvwFacHhij1ifzJGHsc3o=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=SQ72rCSPvOXUAG5ariXK8uIOIBT+2ArBQUJXOx+T9HnU3aJHkcCPCCVR60Uv+gVNI 7sQX5qrLt0zytvelBdTL1DtrCqGI45CqXSe5IIff6JaboF3MNqOZZ6QphGkR5WYEZ/ ZF1zv9QVPZGKIIgAU4v3fLWiB38KBZpMAj1VEb98= Received: by paulmck-ThinkPad-P72.home (Postfix, from userid 1000) id 1A3D835225E2; Tue, 3 Nov 2020 07:18:03 -0800 (PST) Date: Tue, 3 Nov 2020 07:18:03 -0800 From: "Paul E. McKenney" To: Joel Fernandes Cc: Frederic Weisbecker , linux-kernel@vger.kernel.org, Josh Triplett , Lai Jiangshan , Marco Elver , Mathieu Desnoyers , rcu@vger.kernel.org, Steven Rostedt , "Uladzislau Rezki (Sony)" , fweisbec@gmail.com, neeraj.iitr10@gmail.com Subject: Re: [PATCH v9 3/7] srcu: Fix invoke_rcu_callbacks() segcb length adjustment Message-ID: <20201103151803.GB3249@paulmck-ThinkPad-P72> Reply-To: paulmck@kernel.org References: <20201103142603.1302207-1-joel@joelfernandes.org> <20201103142603.1302207-4-joel@joelfernandes.org> <20201103144714.GA432431@lothringen> <20201103150738.GB1304393@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201103150738.GB1304393@google.com> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 03, 2020 at 10:07:38AM -0500, Joel Fernandes wrote: > On Tue, Nov 03, 2020 at 03:47:14PM +0100, Frederic Weisbecker wrote: > > On Tue, Nov 03, 2020 at 09:25:59AM -0500, Joel Fernandes (Google) wrote: > > > With earlier patches, the negative counting of the unsegmented list > > > cannot be used to adjust the segmented one. To fix this, sample the > > > unsegmented length in advance, and use it after CB execution to adjust > > > the segmented list's length. > > > > > > Reviewed-by: Frederic Weisbecker > > > Suggested-by: Frederic Weisbecker > > > Signed-off-by: Joel Fernandes (Google) > > > > This breaks bisection, you need to either fix up the previous patch > > by adding this diff inside or better yet: expand what you did > > in "rcu/tree: Make rcu_do_batch count how many callbacks were executed" > > to also handle srcu before introducing the segcb count. > > Since doing the latter is a lot more tedious and I want to get reviewing > other's RCU patches today :) , I just squashed the suggestion into the > counters patch to fix bissection: > https://git.kernel.org/pub/scm/linux/kernel/git/jfern/linux.git/commit/?h=rcu/segcb-counts&id=595e3a65eeef109cb8fcbfcc114fd3ea2064b873 > > Hope that's Ok. Also, so that I don't have to resend everything, here is the > final branch if Paul wants to take it: > git://git.kernel.org/pub/scm/linux/kernel/git/jfern/linux.git (branch rcu/segcb-counts) Either way, it sounds like it is time for me to review this series. Thank you both very much!!! Thaxn, Paul