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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 9BF38C47240 for ; Thu, 3 Jun 2021 05:23:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 822FB613F0 for ; Thu, 3 Jun 2021 05:23:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229807AbhFCFYx (ORCPT ); Thu, 3 Jun 2021 01:24:53 -0400 Received: from mail109.syd.optusnet.com.au ([211.29.132.80]:45122 "EHLO mail109.syd.optusnet.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229640AbhFCFYw (ORCPT ); Thu, 3 Jun 2021 01:24:52 -0400 Received: from dread.disaster.area (pa49-179-138-183.pa.nsw.optusnet.com.au [49.179.138.183]) by mail109.syd.optusnet.com.au (Postfix) with ESMTPS id F2F0B68072 for ; Thu, 3 Jun 2021 15:22:50 +1000 (AEST) Received: from discord.disaster.area ([192.168.253.110]) by dread.disaster.area with esmtp (Exim 4.92.3) (envelope-from ) id 1lofog-008Mq2-DE for linux-xfs@vger.kernel.org; Thu, 03 Jun 2021 15:22:50 +1000 Received: from dave by discord.disaster.area with local (Exim 4.94) (envelope-from ) id 1lofog-000ilN-5S for linux-xfs@vger.kernel.org; Thu, 03 Jun 2021 15:22:50 +1000 From: Dave Chinner To: linux-xfs@vger.kernel.org Subject: [PATCH 04/39] xfs: async blkdev cache flush Date: Thu, 3 Jun 2021 15:22:05 +1000 Message-Id: <20210603052240.171998-5-david@fromorbit.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210603052240.171998-1-david@fromorbit.com> References: <20210603052240.171998-1-david@fromorbit.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Optus-CM-Score: 0 X-Optus-CM-Analysis: v=2.3 cv=F8MpiZpN c=1 sm=1 tr=0 a=MnllW2CieawZLw/OcHE/Ng==:117 a=MnllW2CieawZLw/OcHE/Ng==:17 a=r6YtysWOX24A:10 a=20KFwNOVAAAA:8 a=VwQbUJbxAAAA:8 a=yPCof4ZbAAAA:8 a=xC2MDfIwAKB5AMCYbWUA:9 a=AjGcO6oz07-iQ99wixmX:22 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org From: Dave Chinner The new checkpoint cache flush mechanism requires us to issue an unconditional cache flush before we start a new checkpoint. We don't want to block for this if we can help it, and we have a fair chunk of CPU work to do between starting the checkpoint and issuing the first journal IO. Hence it makes sense to amortise the latency cost of the cache flush by issuing it asynchronously and then waiting for it only when we need to issue the first IO in the transaction. To do this, we need async cache flush primitives to submit the cache flush bio and to wait on it. The block layer has no such primitives for filesystems, so roll our own for the moment. Signed-off-by: Dave Chinner Reviewed-by: Brian Foster Reviewed-by: Darrick J. Wong Reviewed-by: Allison Henderson --- fs/xfs/xfs_bio_io.c | 35 +++++++++++++++++++++++++++++++++++ fs/xfs/xfs_linux.h | 2 ++ 2 files changed, 37 insertions(+) diff --git a/fs/xfs/xfs_bio_io.c b/fs/xfs/xfs_bio_io.c index 17f36db2f792..667e297f59b1 100644 --- a/fs/xfs/xfs_bio_io.c +++ b/fs/xfs/xfs_bio_io.c @@ -9,6 +9,41 @@ static inline unsigned int bio_max_vecs(unsigned int count) return bio_max_segs(howmany(count, PAGE_SIZE)); } +static void +xfs_flush_bdev_async_endio( + struct bio *bio) +{ + complete(bio->bi_private); +} + +/* + * Submit a request for an async cache flush to run. If the request queue does + * not require flush operations, just skip it altogether. If the caller needs + * to wait for the flush completion at a later point in time, they must supply a + * valid completion. This will be signalled when the flush completes. The + * caller never sees the bio that is issued here. + */ +void +xfs_flush_bdev_async( + struct bio *bio, + struct block_device *bdev, + struct completion *done) +{ + struct request_queue *q = bdev->bd_disk->queue; + + if (!test_bit(QUEUE_FLAG_WC, &q->queue_flags)) { + complete(done); + return; + } + + bio_init(bio, NULL, 0); + bio_set_dev(bio, bdev); + bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC; + bio->bi_private = done; + bio->bi_end_io = xfs_flush_bdev_async_endio; + + submit_bio(bio); +} int xfs_rw_bdev( struct block_device *bdev, diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h index 7688663b9773..c174262a074e 100644 --- a/fs/xfs/xfs_linux.h +++ b/fs/xfs/xfs_linux.h @@ -196,6 +196,8 @@ static inline uint64_t howmany_64(uint64_t x, uint32_t y) int xfs_rw_bdev(struct block_device *bdev, sector_t sector, unsigned int count, char *data, unsigned int op); +void xfs_flush_bdev_async(struct bio *bio, struct block_device *bdev, + struct completion *done); #define ASSERT_ALWAYS(expr) \ (likely(expr) ? (void)0 : assfail(NULL, #expr, __FILE__, __LINE__)) -- 2.31.1