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 lists.sourceforge.net (lists.sourceforge.net [216.105.38.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D79F4C433F5 for ; Fri, 4 Feb 2022 09:10:24 +0000 (UTC) Received: from [127.0.0.1] (helo=sfs-ml-4.v29.lw.sourceforge.com) by sfs-ml-4.v29.lw.sourceforge.com with esmtp (Exim 4.94.2) (envelope-from ) id 1nFubn-0000zN-LZ; Fri, 04 Feb 2022 09:10:22 +0000 Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-4.v29.lw.sourceforge.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1nFubm-0000zG-D9 for linux-f2fs-devel@lists.sourceforge.net; Fri, 04 Feb 2022 09:10:21 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=Content-Transfer-Encoding:MIME-Version:Message-Id: Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=2r7rBA6cLE/LOayn17wccFuuRsJss8BPtmJcgffPGEQ=; b=CoF9QfvuL3V1Im6Hr1V7+mBYfX DaNNI0PuRKoSFKcAn+lOBEEj0V5WO4PZGSGJ+dvAjG7rcMul6VL/xRVRky9BjLXRTauFU0Zoi6jwK zzNQBDqgjiqQZ6agRYL6nZteNRFO3J+I9OPRHh4qSrojvpsYL1L8PjVIg+jUUlatdJ0c=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=Content-Transfer-Encoding:MIME-Version:Message-Id:Date:Subject:Cc:To:From :Sender:Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To: References:List-Id:List-Help:List-Unsubscribe:List-Subscribe:List-Post: List-Owner:List-Archive; bh=2r7rBA6cLE/LOayn17wccFuuRsJss8BPtmJcgffPGEQ=; b=g vn8UZlO9G7qEXaeR45+bA93aDPK9hWRPXrS0B8EyKcc3AGEo/ZoisGAS5R4cpmSqi7KGwk4k3ZNRh R0e6ES+RrHce3vRQ+msBldKAF3c+4tTZyyBzp8nDshp+d40DrboqHWnchAW2BID2dNmDKMz3Id0Ip 4KvLlOLrdxsWwhI0=; Received: from dfw.source.kernel.org ([139.178.84.217]) by sfi-mx-1.v28.lw.sourceforge.com with esmtps (TLS1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.94.2) id 1nFubj-00GnAn-Iw for linux-f2fs-devel@lists.sourceforge.net; Fri, 04 Feb 2022 09:10:20 +0000 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 06A4A614DB for ; Fri, 4 Feb 2022 09:10:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8C49EC004E1; Fri, 4 Feb 2022 09:10:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1643965810; bh=rb2wJPVBUi7SSDcM4ZjaKH33BmO66QdukLi4kREAYQI=; h=From:To:Cc:Subject:Date:From; b=QLs72LqEdqR3krZ4rfFl6N0Y022GIXBLQT7CASXshBCbmJR4eaoUkFW6Bj/mpwIjl 5U46GAG2PSww5Jyz8GiHrOf0cmNSYo8msB2NER2o7+QovY+lcJx/MelOPIJQL70Twf lI+gwvnEpF3H/WKFWdfAa72VrDRIht98zwml5r7Zjx6e2RQSVnUwrObKr+BPEAsLJb TCf6IwNM8wQt9GRjmQC9qmfH9Kf9WKEO7nLAMcgljS+rzFG2ZU0jEV/8sDymrC9svm Y6Vvas16EHjhzOQyuV04K03E2YqB/OzoZo4dnME0nhDFqMe4tPMBSguChEZ9DYkBT8 8jBeaCxPEqh/w== From: Chao Yu To: jaegeuk@kernel.org Date: Fri, 4 Feb 2022 17:10:05 +0800 Message-Id: <20220204091005.49407-1-chao@kernel.org> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 X-Headers-End: 1nFubj-00GnAn-Iw Subject: [f2fs-dev] [PATCH v2] f2fs: skip f2fs_preallocate_blocks() for overwrite case X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net There is potential hangtask happened during swapfile's writeback: - loop_kthread_worker_fn - do_checkpoint - kthread_worker_fn - loop_queue_work - lo_rw_aio - f2fs_file_write_iter - f2fs_preallocate_blocks - f2fs_map_blocks - down_write - down_read - rwsem_down_read_slowpath - schedule One cause is f2fs_preallocate_blocks() will always be called no matter the physical block addresses are allocated or not. This patch tries to check whether block addresses are all allocated with i_size and i_blocks of inode, it's rough because blocks can be allocated beyond i_size, however, we can afford skipping block preallocation in this condition since it's not necessary to do preallocation all the time. Signed-off-by: Chao Yu --- v2: - check overwrite case with i_size and i_blocks roughly. fs/f2fs/file.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index cfdc41f87f5d..09565d10611d 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -4390,6 +4390,16 @@ static int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *iter, int flag; int ret; + /* + * It tries to check whether block addresses are all allocated, + * it's rough because blocks can be allocated beyond i_size, + * however, we can afford skipping block preallocation since + * it's not necessary all the time. + */ + if (F2FS_BLK_ALIGN(i_size_read(inode)) == + SECTOR_TO_BLOCK(inode->i_blocks)) + return 0; + /* If it will be an out-of-place direct write, don't bother. */ if (dio && f2fs_lfs_mode(sbi)) return 0; -- 2.32.0 _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel