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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 69982C43461 for ; Mon, 31 Aug 2020 18:08:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 42DC420866 for ; Mon, 31 Aug 2020 18:08:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598897283; bh=XG3jWVOIYHjwWZSiiTWlyu/bevtJTbO3eo5mHlAXsaA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ansi+5G5XaVu+s15h+1aSPWIS8wnS8n0NSTcsoaqGCzJMaB06+ebOzbK69jOJdBdM RLC31sCiGi4HlCnK2RgscvEsCxKIUjmlZ+jcZXTW49gfeGQhX2KmVtAucXpr7syINJ wtWYrUtFociYVfik2hJcupX/gysyZ5eAidyIeoa4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729352AbgHaSIB (ORCPT ); Mon, 31 Aug 2020 14:08:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:55408 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729234AbgHaSHx (ORCPT ); Mon, 31 Aug 2020 14:07:53 -0400 Received: from paulmck-ThinkPad-P72.home (unknown [50.45.173.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A99CC21532; Mon, 31 Aug 2020 18:07:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598897272; bh=XG3jWVOIYHjwWZSiiTWlyu/bevtJTbO3eo5mHlAXsaA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yMf3lsA8nPiKgVqR1b5jO90o9OwkPAol9ofL23gcc92J+lPZFp1XzRaRbZg2Oqdh0 +MNZY63zdaJoKGNJMn0r7PiR+IRXMkagb5q53puVUR0HuKcSW6IuCncuCl6SnSWQFl 6rINmRSUD9o+PTgXSf7cVSvR2Q1SesxqXk6Yhwxs= From: paulmck@kernel.org To: rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@fb.com, mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 05/19] tick-sched: Clarify "NOHZ: local_softirq_pending" warning Date: Mon, 31 Aug 2020 11:07:35 -0700 Message-Id: <20200831180749.843-5-paulmck@kernel.org> X-Mailer: git-send-email 2.9.5 In-Reply-To: <20200831180731.GA582@paulmck-ThinkPad-P72> References: <20200831180731.GA582@paulmck-ThinkPad-P72> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Paul E. McKenney" Currently, can_stop_idle_tick() prints "NOHZ: local_softirq_pending HH" (where "HH" is the hexadecimal softirq vector number) when one or more non-RCU softirq handlers are still enabled when checking to stop the scheduler-tick interrupt. This message is not as enlightening as one might hope, so this commit changes it to "NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #HH". Reported-by: Andy Lutomirski Cc: Frederic Weisbecker Cc: Thomas Gleixner Cc: Ingo Molnar Signed-off-by: Paul E. McKenney --- kernel/time/tick-sched.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index f0199a4..81632cd 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -927,7 +927,7 @@ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts) if (ratelimit < 10 && (local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) { - pr_warn("NOHZ: local_softirq_pending %02x\n", + pr_warn("NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #%02x!!!\n", (unsigned int) local_softirq_pending()); ratelimit++; } -- 2.9.5