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 A3542C433F5 for ; Fri, 18 Mar 2022 06:47:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232784AbiCRGsi (ORCPT ); Fri, 18 Mar 2022 02:48:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49710 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230170AbiCRGsf (ORCPT ); Fri, 18 Mar 2022 02:48:35 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1F996183831; Thu, 17 Mar 2022 23:47:17 -0700 (PDT) Received: from dggpeml500023.china.huawei.com (unknown [172.30.72.56]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4KKZJS5QH9zCqkX; Fri, 18 Mar 2022 14:45:12 +0800 (CST) Received: from dggpeml500018.china.huawei.com (7.185.36.186) by dggpeml500023.china.huawei.com (7.185.36.114) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Fri, 18 Mar 2022 14:47:15 +0800 Received: from [10.67.111.186] (10.67.111.186) by dggpeml500018.china.huawei.com (7.185.36.186) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Fri, 18 Mar 2022 14:47:15 +0800 Message-ID: <07787055-6aaf-3abb-a9fd-b8dd4180ebe8@huawei.com> Date: Fri, 18 Mar 2022 14:47:14 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.1.1 Subject: Re: [PATCH] rcu: Use printk_deferred when holding rtp->cbs_gbl_lock To: Steven Rostedt CC: , , , , , , References: <20220317084726.77336-1-zhangqiao22@huawei.com> <20220317114924.791c6500@gandalf.local.home> From: Zhang Qiao In-Reply-To: <20220317114924.791c6500@gandalf.local.home> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-Originating-IP: [10.67.111.186] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpeml500018.china.huawei.com (7.185.36.186) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2022/3/17 23:49, Steven Rostedt 写道: > On Thu, 17 Mar 2022 16:47:26 +0800 > Zhang Qiao wrote: > >> This patch tries to avoid this issue by using printk_deferred(). > > Isn't the new printk work suppose to resolve this? > I think the printk_deferred() defer printing via a irq_work_queue and will not print immediately when holding the cbs_gbl_lock lock. > If so, can we have another way to quiet these splats if that work is not in > yet? > Or we can change type cbs_gbl_lock to spinlock_t for fix it. thanks. Zhang Qiao. > -- Steve > . >