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=-20.4 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,USER_AGENT_GIT autolearn=unavailable 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 8DA9DC07E9B for ; Mon, 5 Jul 2021 15:32:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7906761997 for ; Mon, 5 Jul 2021 15:32:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233174AbhGEPez (ORCPT ); Mon, 5 Jul 2021 11:34:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:58662 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231986AbhGEPcv (ORCPT ); Mon, 5 Jul 2021 11:32:51 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7BB8A619A4; Mon, 5 Jul 2021 15:30:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625499014; bh=bBqbVgGtHhYTPkgSoIkjqz5PTnzkvCn2RFMFe4PV48k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lYOvcxeHNInQSMgC5xznojE1udcEeyk8DnUo0RFBekuE2GmaPKXo8GtyJGjOyXWVK 3rUZImmsMCKzkpuaPcrQGw28cKSAsNWTTpbDz3JbpzSsCzeD5wyzo6QbAhB14gQZJh EPcNC5YoYWQMJxBu6F2cIWu+rTylP0aHPHURPL2QT2k5vUALbre7EsvU9i8w6WJ8kS rDoydmc6M0brjUhiaAl14NEh37m/RYGcNo/Jc64qbowE9XZx3N0gkFHYYsqRMVWmHt vNfTrdcZ+SzKpsQ+sjsvDUWoFTr4lz475GQCLA27FJydoY4dO4z4JoVPW1b7RatUYP I7Ok6y3mYvTuQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "zhangyi (F)" , Jan Kara , Christoph Hellwig , Jens Axboe , Sasha Levin , linux-fsdevel@vger.kernel.org Subject: [PATCH AUTOSEL 5.10 10/41] block_dump: remove block_dump feature in mark_inode_dirty() Date: Mon, 5 Jul 2021 11:29:30 -0400 Message-Id: <20210705153001.1521447-10-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210705153001.1521447-1-sashal@kernel.org> References: <20210705153001.1521447-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "zhangyi (F)" [ Upstream commit 12e0613715e1cf305fffafaf0e89d810d9a85cc0 ] block_dump is an old debugging interface, one of it's functions is used to print the information about who write which file on disk. If we enable block_dump through /proc/sys/vm/block_dump and turn on debug log level, we can gather information about write process name, target file name and disk from kernel message. This feature is realized in block_dump___mark_inode_dirty(), it print above information into kernel message directly when marking inode dirty, so it is noisy and can easily trigger log storm. At the same time, get the dentry refcount is also not safe, we found it will lead to deadlock on ext4 file system with data=journal mode. After tracepoints has been introduced into the kernel, we got a tracepoint in __mark_inode_dirty(), which is a better replacement of block_dump___mark_inode_dirty(). The only downside is that it only trace the inode number and not a file name, but it probably doesn't matter because the original printed file name in block_dump is not accurate in some cases, and we can still find it through the inode number and device id. So this patch delete the dirting inode part of block_dump feature. Signed-off-by: zhangyi (F) Reviewed-by: Jan Kara Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20210313030146.2882027-2-yi.zhang@huawei.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- fs/fs-writeback.c | 25 ------------------------- 1 file changed, 25 deletions(-) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 90dddb507e4a..0d0f014b09ec 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -2196,28 +2196,6 @@ int dirtytime_interval_handler(struct ctl_table *table, int write, return ret; } -static noinline void block_dump___mark_inode_dirty(struct inode *inode) -{ - if (inode->i_ino || strcmp(inode->i_sb->s_id, "bdev")) { - struct dentry *dentry; - const char *name = "?"; - - dentry = d_find_alias(inode); - if (dentry) { - spin_lock(&dentry->d_lock); - name = (const char *) dentry->d_name.name; - } - printk(KERN_DEBUG - "%s(%d): dirtied inode %lu (%s) on %s\n", - current->comm, task_pid_nr(current), inode->i_ino, - name, inode->i_sb->s_id); - if (dentry) { - spin_unlock(&dentry->d_lock); - dput(dentry); - } - } -} - /** * __mark_inode_dirty - internal function * @@ -2277,9 +2255,6 @@ void __mark_inode_dirty(struct inode *inode, int flags) (dirtytime && (inode->i_state & I_DIRTY_INODE))) return; - if (unlikely(block_dump)) - block_dump___mark_inode_dirty(inode); - spin_lock(&inode->i_lock); if (dirtytime && (inode->i_state & I_DIRTY_INODE)) goto out_unlock_inode; -- 2.30.2