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=-4.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 72850C2D0A3 for ; Mon, 26 Oct 2020 11:29:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2824C22265 for ; Mon, 26 Oct 2020 11:29:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603711742; bh=zJ7XyYSVCAPouO33DFnMP7X1CmubkeNekzhvy9XpCqU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=NEgEqLc0+gE7AKzTTb+nqoVI+UevSnTMdi5RNxp5J03OeKwgZf/hK+L5XRWsJdoOP r0SQdSK5B/W4SeV48lLtuUxr5o+11q04vS3h2vSuF/8CPtarVo8J3xnjPBnxmXfBpB pSn93yPoIQ1jbkMk/6TSdqHYjQMYr4Tu8pseP1b4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1773796AbgJZL3B (ORCPT ); Mon, 26 Oct 2020 07:29:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:52400 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1771749AbgJZL3A (ORCPT ); Mon, 26 Oct 2020 07:29:00 -0400 Received: from localhost (unknown [176.177.109.29]) (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 E1EB722263; Mon, 26 Oct 2020 11:28:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603711740; bh=zJ7XyYSVCAPouO33DFnMP7X1CmubkeNekzhvy9XpCqU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=IQVWFd9RJxCAJzfkVoE8YaP+S0n6bMz2uho1yvgl4cExEqKwu5MXwFiI4vkyoxRm8 q6Gz4n3IEfvsuzeqCceeJwH7EEHlzro8cpalFjRTK3u3V0L98QL95b0/mI8PG2ZfkE RuRN1KL6K2l/2XFC0p4MXQ3+K2qmoTYG52r7Lp6A= Date: Mon, 26 Oct 2020 12:28:57 +0100 From: Frederic Weisbecker To: Joel Fernandes 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 v8 2/6] rcu/segcblist: Add counters to segcblist datastructure Message-ID: <20201026112857.GD104441@lothringen> References: <20201021190813.3005054-1-joel@joelfernandes.org> <20201021190813.3005054-3-joel@joelfernandes.org> <20201026005058.GB104441@lothringen> <20201026054557.GB4192074@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201026054557.GB4192074@google.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 26, 2020 at 01:45:57AM -0400, Joel Fernandes wrote: > On Mon, Oct 26, 2020 at 01:50:58AM +0100, Frederic Weisbecker wrote: > > On Wed, Oct 21, 2020 at 03:08:09PM -0400, Joel Fernandes (Google) wrote: > > > bool rcu_segcblist_accelerate(struct rcu_segcblist *rsclp, unsigned long seq) > > > { > > > - int i; > > > + int i, j; > > > > > > WARN_ON_ONCE(!rcu_segcblist_is_enabled(rsclp)); > > > if (rcu_segcblist_restempty(rsclp, RCU_DONE_TAIL)) > > > @@ -487,6 +508,10 @@ bool rcu_segcblist_accelerate(struct rcu_segcblist *rsclp, unsigned long seq) > > > if (rcu_segcblist_restempty(rsclp, i) || ++i >= RCU_NEXT_TAIL) > > > return false; > > > > > > + /* Accounting: everything below i is about to get merged into i. */ > > > + for (j = i + 1; j <= RCU_NEXT_TAIL; j++) > > > + rcu_segcblist_move_seglen(rsclp, j, i); > > > + > > > > Can you perhaps reuse the below loop to move the seglen? > > Not easily, because we will need to store 'i' into another variable then, which > does not change. > > Besides IMHO, the code is more readable with the loops separated. Works for me. Thanks!