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=-17.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 4FEFBC43381 for ; Tue, 16 Mar 2021 14:02:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2BB9A65072 for ; Tue, 16 Mar 2021 14:02:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235786AbhCPOC2 (ORCPT ); Tue, 16 Mar 2021 10:02:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:59452 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235317AbhCPOCB (ORCPT ); Tue, 16 Mar 2021 10:02:01 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id E2ECA65053; Tue, 16 Mar 2021 14:02:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1615903320; bh=FZlNhG0GbjjaNOwyUjz7LHRtAsYWpow/g2cDQKBuMpU=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=M4tVvyoJ2HYEVe7OYjXMQ334CmYs4EXr2j/Ui8RoA9OfMuGhfm4aNEKQPTq4SZ/ij Lsp1m1QcIRRbLM7GSVxvrMNqVbjtMHDydGV7hZB5t46Ol+pZjia3Wcf3CBLuf6ji15 EXMVkT2OakNTnF2nrXMUZrINh5ZkbPTRPit+pYRyCm5ZsCFr5ACUFz7BoJORuqj/AL kyuJe1SWJVDnvucLqsBq/k5OfwTa6VymGbh3GZ5MsZl0KKdawrtV/BhwyW6V4eyIoU WkHAiGG9AQVKSeTenZvIJcELPj/13nQ2X4j/GYN4Azybhk2UZVWewvoCnt7CVBox8l m7sKSL/wUC8mA== Received: by paulmck-ThinkPad-P72.home (Postfix, from userid 1000) id A1E51352262D; Tue, 16 Mar 2021 07:02:00 -0700 (PDT) Date: Tue, 16 Mar 2021 07:02:00 -0700 From: "Paul E. McKenney" To: Frederic Weisbecker Cc: LKML , Thomas Gleixner , Boqun Feng , Lai Jiangshan , Neeraj Upadhyay , Josh Triplett , Stable , Joel Fernandes Subject: Re: [PATCH 12/13] rcu/nocb: Prepare for finegrained deferred wakeup Message-ID: <20210316140200.GT2696@paulmck-ThinkPad-P72> Reply-To: paulmck@kernel.org References: <20210223001011.127063-1-frederic@kernel.org> <20210223001011.127063-13-frederic@kernel.org> <20210316030239.GA13675@paulmck-ThinkPad-P72> <20210316114526.GA639918@lothringen> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210316114526.GA639918@lothringen> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 16, 2021 at 12:45:26PM +0100, Frederic Weisbecker wrote: > On Mon, Mar 15, 2021 at 08:02:39PM -0700, Paul E. McKenney wrote: > > On Tue, Feb 23, 2021 at 01:10:10AM +0100, Frederic Weisbecker wrote: > > > Provide a way to tune the deferred wakeup level we want to perform from > > > a safe wakeup point. Currently those sites are: > > > > > > * nocb_timer > > > * user/idle/guest entry > > > * CPU down > > > * softirq/rcuc > > > > > > All of these sites perform the wake up for both RCU_NOCB_WAKE and > > > RCU_NOCB_WAKE_FORCE. > > > > > > In order to merge nocb_timer and nocb_bypass_timer together, we plan to > > > add a new RCU_NOCB_WAKE_BYPASS that really want to be deferred until > > > a timer fires so that we don't wake up the NOCB-gp kthread too early. > > > > > > To prepare for that, integrate a wake up level/limit that a callsite is > > > deemed to perform. > > > > This appears to need the following in order to build for non-NOCB > > configurations. I will fold it in and am retesting. > > > > Thanx, Paul > > > > ------------------------------------------------------------------------ > > > > commit 55f59dd75a11455cf558fd387fbf9011017dcc8a > > Author: Paul E. McKenney > > Date: Mon Mar 15 20:00:34 2021 -0700 > > > > squash! rcu/nocb: Prepare for fine-grained deferred wakeup > > > > [ paulmck: Fix non-NOCB rcu_nocb_need_deferred_wakeup() definition. ] > > Signed-off-by: Paul E. McKenney > > > > diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h > > index 0cc7f68..dfb048e 100644 > > --- a/kernel/rcu/tree_plugin.h > > +++ b/kernel/rcu/tree_plugin.h > > @@ -2926,7 +2926,7 @@ static void __init rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp) > > { > > } > > > > -static int rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp) > > +static int rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp, int level) > > { > > return false; > > } > > Oops thanks, I missed that. And with this, light rcutorture testing passed. I hope to pound on it harder later this week. Thanx, Paul