From patchwork Mon May 16 19:37:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 573762 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 AD704C43217 for ; Mon, 16 May 2022 20:05:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346960AbiEPUFT (ORCPT ); Mon, 16 May 2022 16:05:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44090 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348888AbiEPT7C (ORCPT ); Mon, 16 May 2022 15:59:02 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 001C110B0; Mon, 16 May 2022 12:52:08 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 9061C60A50; Mon, 16 May 2022 19:52:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A0CB2C385AA; Mon, 16 May 2022 19:52:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1652730728; bh=3/viTrq2CJi48RpXpQDqdjV7P1sTUTEI5Kc8yZ9ijAU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XwGdYeAQuiwvCZgBmysyGvD6JL5nWDVTa+oW3de6kPhUmykp6hGgrSGxuJfJ6LbiG 6v+OvzefwwS2h/2oSAjCNHjVUE6EGjAxEi1WyKWaTXLE4NAnIag0BAQ3y7uH+i3rvr DprsfwtXvnGd+89kQpczbNR0gsMlFFIlC0Vjw978= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jan Kara , Christoph Hellwig , Jing Xia Subject: [PATCH 5.15 089/102] writeback: Avoid skipping inode writeback Date: Mon, 16 May 2022 21:37:03 +0200 Message-Id: <20220516193626.553611508@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220516193623.989270214@linuxfoundation.org> References: <20220516193623.989270214@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jing Xia commit 846a3351ddfe4a86eede4bb26a205c3f38ef84d3 upstream. We have run into an issue that a task gets stuck in balance_dirty_pages_ratelimited() when perform I/O stress testing. The reason we observed is that an I_DIRTY_PAGES inode with lots of dirty pages is in b_dirty_time list and standard background writeback cannot writeback the inode. After studing the relevant code, the following scenario may lead to the issue: task1 task2 ----- ----- fuse_flush write_inode_now //in b_dirty_time writeback_single_inode __writeback_single_inode fuse_write_end filemap_dirty_folio __xa_set_mark:PAGECACHE_TAG_DIRTY lock inode->i_lock if mapping tagged PAGECACHE_TAG_DIRTY inode->i_state |= I_DIRTY_PAGES unlock inode->i_lock __mark_inode_dirty:I_DIRTY_PAGES lock inode->i_lock -was dirty,inode stays in -b_dirty_time unlock inode->i_lock if(!(inode->i_state & I_DIRTY_All)) -not true,so nothing done This patch moves the dirty inode to b_dirty list when the inode currently is not queued in b_io or b_more_io list at the end of writeback_single_inode. Reviewed-by: Jan Kara Reviewed-by: Christoph Hellwig CC: stable@vger.kernel.org Fixes: 0ae45f63d4ef ("vfs: add support for a lazytime mount option") Signed-off-by: Jing Xia Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20220510023514.27399-1-jing.xia@unisoc.com Signed-off-by: Greg Kroah-Hartman --- fs/fs-writeback.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -1739,6 +1739,10 @@ static int writeback_single_inode(struct */ if (!(inode->i_state & I_DIRTY_ALL)) inode_cgwb_move_to_attached(inode, wb); + else if (!(inode->i_state & I_SYNC_QUEUED) && + (inode->i_state & I_DIRTY)) + redirty_tail_locked(inode, wb); + spin_unlock(&wb->list_lock); inode_sync_complete(inode); out: