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=-20.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, 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 DBFEBC07E9D for ; Mon, 19 Jul 2021 14:59:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C049861003 for ; Mon, 19 Jul 2021 14:59:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242053AbhGSOTB (ORCPT ); Mon, 19 Jul 2021 10:19:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:52382 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241842AbhGSOSR (ORCPT ); Mon, 19 Jul 2021 10:18:17 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8C266611C1; Mon, 19 Jul 2021 14:58:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626706737; bh=Oq8MBoPTf8nY/K+XPlS22isf5ghOcandDGfC5iijANU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Em+mN7hxLTuGM/dkICIz4JR13QVj8+LdQsBbjTOSsNu/BO7OMg+Kloo5A5b6NkLJl Yddz+rxTW+0JmqUEVCBUx2MqWq0VIAGAYFiGkHpeJxnIWkIGYOYFMN5PzegFQrZIkj R9u2XrssAb6CeD1fW6BlNbR6Dv3f6JqEccu1PSmg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "zhangyi (F)" , Jan Kara , Christoph Hellwig , Jens Axboe , Sasha Levin Subject: [PATCH 4.4 042/188] block_dump: remove block_dump feature in mark_inode_dirty() Date: Mon, 19 Jul 2021 16:50:26 +0200 Message-Id: <20210719144922.927756599@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210719144913.076563739@linuxfoundation.org> References: <20210719144913.076563739@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 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 7f068330edb6..958a1bd0b5fc 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -2040,28 +2040,6 @@ 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 * @inode: inode to mark @@ -2120,9 +2098,6 @@ 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