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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D388FC19F2D for ; Thu, 4 Aug 2022 02:34:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239259AbiHDCeu (ORCPT ); Wed, 3 Aug 2022 22:34:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59598 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229758AbiHDCes (ORCPT ); Wed, 3 Aug 2022 22:34:48 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5B0DA5FAE7; Wed, 3 Aug 2022 19:34:47 -0700 (PDT) Received: from dggpemm500023.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4Lyt5p0pvTzjXfp; Thu, 4 Aug 2022 10:31:42 +0800 (CST) Received: from dggpemm500006.china.huawei.com (7.185.36.236) by dggpemm500023.china.huawei.com (7.185.36.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 4 Aug 2022 10:34:45 +0800 Received: from thunder-town.china.huawei.com (10.174.178.55) by dggpemm500006.china.huawei.com (7.185.36.236) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 4 Aug 2022 10:34:44 +0800 From: Zhen Lei To: Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , "Mel Gorman" , Daniel Bristot de Oliveira , Valentin Schneider , , "Paul E . McKenney" , Frederic Weisbecker , Neeraj Upadhyay , "Josh Triplett" , Mathieu Desnoyers , Lai Jiangshan , Joel Fernandes , CC: Zhen Lei Subject: [PATCH v4 0/2] rcu: Display registers of self-detected stall as far as possible Date: Thu, 4 Aug 2022 10:34:18 +0800 Message-ID: <20220804023420.1663-1-thunder.leizhen@huawei.com> X-Mailer: git-send-email 2.26.0.windows.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.174.178.55] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpemm500006.china.huawei.com (7.185.36.236) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org v3 --> v4: 1. To avoid undo/redo, merge patch 1-2 in v3 into one. v2 --> v3: 1. Patch 1 Add trigger_single_cpu_backtrace(cpu) in synchronize_rcu_expedited_wait() Subsequently, we can see that all callers of dump_cpu_task() try trigger_single_cpu_backtrace() first. Then I do the cleanup in Patch 2. 2. Patch 3, as Paul E. McKenney's suggestion, push the code into dump_cpu_task(). For newcomers: Currently, dump_cpu_task() is mainly used by RCU, in order to dump the stack traces of the current task of the specified CPU when a rcu stall is detected. For architectures that do not support NMI interrupts, registers is not printed when rcu stall is self-detected. This patch series improve it. v2: https://lkml.org/lkml/2022/7/27/1800 Zhen Lei (2): sched/debug: Try trigger_single_cpu_backtrace(cpu) in dump_cpu_task() sched/debug: Show the registers of 'current' in dump_cpu_task() kernel/rcu/tree_stall.h | 8 +++----- kernel/sched/core.c | 14 ++++++++++++++ kernel/smp.c | 3 +-- 3 files changed, 18 insertions(+), 7 deletions(-) -- 2.25.1