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=-14.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 72DBDC433E7 for ; Fri, 9 Oct 2020 06:35:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1A8B622254 for ; Fri, 9 Oct 2020 06:35:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="gJ2FCCr6"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="vTApOnil" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732131AbgJIGfy (ORCPT ); Fri, 9 Oct 2020 02:35:54 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:55594 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732015AbgJIGfh (ORCPT ); Fri, 9 Oct 2020 02:35:37 -0400 Date: Fri, 09 Oct 2020 06:35:35 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1602225335; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=LPkTdcPUCdKrCLgh51HE//SNhTebXCVLktJ5NJZ3Dgs=; b=gJ2FCCr6+apqvCeL/nNkyN0ijdIfxcVAZqYfnLcPWnrsXRMNpVozgO3qAC0VUzsaJGJqbu C5cEwIKhZMXhvZZ1VbHe93r6B6iDyAuUnmjAQ2VmL+y80OtC/o/ufwNHU32eq0VNPsTl6E ZWA5OZMW1S8KBIPjgA7AfAHcs4ztn8RSzIEAWIRDgStfts8+6v4Ds4vGVMpFcSqn9ZF7QE sUDSN8Hg818OpTKncYSqleCRVTw7JWE0xKtW1Y257OXKYPI8pIrDRQZWC2FBwVj7713ucf FtTymca1n7iTMuQYnauJVLzQ7VxLQLtr/td0O4K/jKuZ+fnQEj4MVx+kDYwofQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1602225335; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=LPkTdcPUCdKrCLgh51HE//SNhTebXCVLktJ5NJZ3Dgs=; b=vTApOnilTDgbMBBEz7ikuUEOlajRkBEJDqM91w7Jtn2eemqpyxKWxpKtMtStQeQKlokAJ0 pBYC8M+EN4xJKRAA== From: "tip-bot2 for Joel Fernandes (Google)" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: core/rcu] rcu: Clarify comments about FQS loop reporting quiescent states Cc: "Joel Fernandes (Google)" , "Paul E. McKenney" , x86 , LKML MIME-Version: 1.0 Message-ID: <160222533513.7002.3197971404035541858.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the core/rcu branch of tip: Commit-ID: f37599e6f06da47e49c3408afe66c5b6e83a90bd Gitweb: https://git.kernel.org/tip/f37599e6f06da47e49c3408afe66c5b6e83a90bd Author: Joel Fernandes (Google) AuthorDate: Fri, 07 Aug 2020 13:07:19 -04:00 Committer: Paul E. McKenney CommitterDate: Mon, 24 Aug 2020 18:37:55 -07:00 rcu: Clarify comments about FQS loop reporting quiescent states Since at least v4.19, the FQS loop no longer reports quiescent states for offline CPUs except in emergency situations. This commit therefore fixes the comment in rcu_gp_init() to match the current code. Signed-off-by: Joel Fernandes (Google) Signed-off-by: Paul E. McKenney --- kernel/rcu/tree.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 52108dd..2c7afe4 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1706,10 +1706,13 @@ static bool rcu_gp_init(void) raw_spin_unlock_irq_rcu_node(rnp); /* - * Apply per-leaf buffered online and offline operations to the - * rcu_node tree. Note that this new grace period need not wait - * for subsequent online CPUs, and that quiescent-state forcing - * will handle subsequent offline CPUs. + * Apply per-leaf buffered online and offline operations to + * the rcu_node tree. Note that this new grace period need not + * wait for subsequent online CPUs, and that RCU hooks in the CPU + * offlining path, when combined with checks in this function, + * will handle CPUs that are currently going offline or that will + * go offline later. Please also refer to "Hotplug CPU" section + * of RCU's Requirements documentation. */ rcu_state.gp_state = RCU_GP_ONOFF; rcu_for_each_leaf_node(rnp) {