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=-19.4 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,URIBL_BLOCKED,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 7D695C4332F for ; Wed, 15 Sep 2021 23:46:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6751C61157 for ; Wed, 15 Sep 2021 23:46:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233297AbhIOXra (ORCPT ); Wed, 15 Sep 2021 19:47:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:49528 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233157AbhIOXr0 (ORCPT ); Wed, 15 Sep 2021 19:47:26 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 49C006120D; Wed, 15 Sep 2021 23:46:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1631749566; bh=tX6PK4Xu/jV33tVuc75TOgCLcTmhlRNJ/OIgyOD6Nbg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aB6K4O8vxW3OnwOnn00I1kfG5FUUZyh2oEs1WS+RF9IiCyqcYOMFXnlgP+ei9WJuL sd9Oqk2Tc7L467Abc9HN3z1/a7cnT2yb8P7hzIY41CtOOO0VBv69O+T6ac8LoexPyk mIZdQ6Rx1XelU1baOjn1cy35v2z9Va4OyG/VayfegkwUo7fNBkg1zqT9F0TQoVWlJ9 XWQcOKJPUiFJeWSF/ZXOfSe5aHWRIVANX6JjwmrWMM92VmO+Kl4AV5eUUkoP8LQpBx T9un5d0yO56VyO8oXrBT7sOaDp9qAgRdTpuN/7hisY8Qk9SOuDtNa6s23KhMmsMxim mIKzXSoCLFWpw== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id CDFE25C0B1B; Wed, 15 Sep 2021 16:46:05 -0700 (PDT) From: "Paul E. McKenney" To: rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@fb.com, mingo@kernel.org, jiangshanlai@gmail.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, Neeraj Upadhyay , "Paul E . McKenney" Subject: [PATCH rcu 09/13] rcu-tasks: Correct comparisons for CPU numbers in show_stalled_task_trace Date: Wed, 15 Sep 2021 16:46:00 -0700 Message-Id: <20210915234604.3907802-9-paulmck@kernel.org> X-Mailer: git-send-email 2.31.1.189.g2e36527f23 In-Reply-To: <20210915234538.GA3907674@paulmck-ThinkPad-P17-Gen-1> References: <20210915234538.GA3907674@paulmck-ThinkPad-P17-Gen-1> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org From: Neeraj Upadhyay Valid CPU numbers can be zero or greater, but the checks for ->trc_ipi_to_cpu and tick_nohz_full_cpu()'s argument are for strictly greater than. This commit therefore corrects the check for no_hz_full cpu in show_stalled_task_trace() so as to include cpu 0. Signed-off-by: Neeraj Upadhyay Signed-off-by: Paul E. McKenney --- kernel/rcu/tasks.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h index e2ec548fc0c4..af7388849bed 100644 --- a/kernel/rcu/tasks.h +++ b/kernel/rcu/tasks.h @@ -1084,9 +1084,9 @@ static void show_stalled_task_trace(struct task_struct *t, bool *firstreport) cpu = task_cpu(t); pr_alert("P%d: %c%c%c nesting: %d%c cpu: %d\n", t->pid, - ".I"[READ_ONCE(t->trc_ipi_to_cpu) > 0], + ".I"[READ_ONCE(t->trc_ipi_to_cpu) >= 0], ".i"[is_idle_task(t)], - ".N"[cpu > 0 && tick_nohz_full_cpu(cpu)], + ".N"[cpu >= 0 && tick_nohz_full_cpu(cpu)], READ_ONCE(t->trc_reader_nesting), " N"[!!READ_ONCE(t->trc_reader_special.b.need_qs)], cpu); -- 2.31.1.189.g2e36527f23