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,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 67E3BC07E9B for ; Mon, 5 Jul 2021 15:34:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5272C61103 for ; Mon, 5 Jul 2021 15:34:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233707AbhGEPhF (ORCPT ); Mon, 5 Jul 2021 11:37:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:58510 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232936AbhGEPey (ORCPT ); Mon, 5 Jul 2021 11:34:54 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id A7F38619AC; Mon, 5 Jul 2021 15:31:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625499083; bh=U7k+PNZbCKVLmzpmoLrO/fWhqyAmpo7Pbowg/bsCwGo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jTexSd7t7DujbnfC2W6px47lxK8+MTWjlxVc2stj4/xidOZPKw6qms/9biD+yAajB RqPYi1PW4cl1jXB60rInMywOWo1zvjGg1SgB0zZwUdwLHQMLUoYYwZNyQSwo5pksB4 Bt7XU3cEIWwZF3SpyRYMHTzYr7T9SsIPkVb9a0bRc5rjZfG8gcGKH/wJ1o3a1+v14x m4SPiZqdmEdCWqVNORPmMaCpjtJllp/Vg865BI6zxOsGqvT1/07KL8DQ1xQrYm58jP W9hrG2sUPtDL6lElpE69DwIJOmM9rJODae3ZfvXSanYpSq54Vt4eV1Y/MX0BU0rx3U mK3HJYFscbRLw== 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 4.19 07/17] block_dump: remove block_dump feature in mark_inode_dirty() Date: Mon, 5 Jul 2021 11:31:03 -0400 Message-Id: <20210705153114.1522046-7-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210705153114.1522046-1-sashal@kernel.org> References: <20210705153114.1522046-1-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 a247cb4b00e2..fc9167e65287 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -2115,28 +2115,6 @@ 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 * @@ -2196,9 +2174,6 @@ 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