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=-7.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 1DCBFC2D0A3 for ; Tue, 3 Nov 2020 14:47:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CAA7122450 for ; Tue, 3 Nov 2020 14:47:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604414845; bh=62SPvuFatUemwtljHtmpCrMGumTbi+10rgi7iVjyUEk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=hUwxn8hZWkt4lPAjZzPGktcjdTUblL/wSRTRtVlxMmq2stpJCciJwtKfcfmbHqSh5 z4UwImjcxuauuI973OG7FniqvXk4CTLwZVvGXAYxKnfxaReL2Zv70xIpy0APa9RYJl TfN4MTgUzEvth4btYmV4bT5R7sQudZFAWjJtzkBE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728286AbgKCOrY (ORCPT ); Tue, 3 Nov 2020 09:47:24 -0500 Received: from mail.kernel.org ([198.145.29.99]:50014 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727553AbgKCOrS (ORCPT ); Tue, 3 Nov 2020 09:47:18 -0500 Received: from localhost (unknown [176.167.46.253]) (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 E79F922370; Tue, 3 Nov 2020 14:47:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604414837; bh=62SPvuFatUemwtljHtmpCrMGumTbi+10rgi7iVjyUEk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=BsL9/V26ECzEN+QHQ7nXC2aCU4nLrGVjUSriAuEIpCGz+QK+kGaRXlGpIF0zsP0V0 +9jBxbqGXcN4ufAJ4CzCCI/QnsCRnNxl2oxGCxQtGewFIWDvjLdy1THto1ZqxmXJv3 5Rx0f6UdDJCm/ZPZ/a5Yvm4Ol8LQJcIhP7334tEk= Date: Tue, 3 Nov 2020 15:47:14 +0100 From: Frederic Weisbecker To: "Joel Fernandes (Google)" Cc: linux-kernel@vger.kernel.org, Josh Triplett , Lai Jiangshan , Marco Elver , Mathieu Desnoyers , "Paul E. McKenney" , 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: <20201103144714.GA432431@lothringen> References: <20201103142603.1302207-1-joel@joelfernandes.org> <20201103142603.1302207-4-joel@joelfernandes.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201103142603.1302207-4-joel@joelfernandes.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. Thanks.