From patchwork Mon Nov 18 11:41:57 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Yu Kuai X-Patchwork-Id: 13878460 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E6D5E1946DA; Mon, 18 Nov 2024 11:44:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731930261; cv=none; b=ctRpFa0SVcBiOvPHjjg00MCpyGG0wVXLZtoUXu4qN2SRjW/9Q7RQrFH+DY+oBYfXQ2q0nZgbxtN2bF/qqmms48rjFHQ6e/wEHEMiVMiGHQ53CyFiowYYSunbpce7B6XGHJu/qP1FLBPmodLcaN6PXIzxtnnPii7O1PgmSD/FeNc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731930261; c=relaxed/simple; bh=n3vffU6ugecXsI4g2DccDSUqlNKS7QvL3JHoGcnE7dI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=l+E7Mi5Cbc/S5V8LnDovl6J06ie7qP1D9eSYd+wLrHfFvjGOKwD43QcFCjlCz/byGPeIh1ICRl/6QEr51iEQBwJ+KZTzkemFPb/h1s8BAlBZALMHZOwx+WU3PbRJjUBmViGsoE1zCLbyN2PRMqre4fsubVHj7Rpq26GDUCjm9fo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4XsQkp4MXRz4f3kKt; Mon, 18 Nov 2024 19:44:02 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id F19901A0568; Mon, 18 Nov 2024 19:44:15 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgBHI4eKKDtn_9+KCA--.2699S9; Mon, 18 Nov 2024 19:44:14 +0800 (CST) From: Yu Kuai To: song@kernel.org, xni@redhat.com Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com Subject: [PATCH md-6.13 5/5] md/md-bitmap: move bitmap_{start, end}write to md upper layer Date: Mon, 18 Nov 2024 19:41:57 +0800 Message-Id: <20241118114157.355749-6-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20241118114157.355749-1-yukuai1@huaweicloud.com> References: <20241118114157.355749-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-raid@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: gCh0CgBHI4eKKDtn_9+KCA--.2699S9 X-Coremail-Antispam: 1UD129KBjvJXoW3ZrWrtr15XF48Gr4Utr4fXwb_yoWkGw1kpa 17Xry5J3y8Gr4YqrW7JFyUuFyrXw1UJry2qry8Jw1Yg3WUJ3yDtFs7WFyUJrn8JFy3CFy7 XF1jyr1UJr1UJwUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBE14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_Ar0_tr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwCY1x0262kKe7AKxVWUAV WUtwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v2 6r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2 Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUCVW8JwCI42IY6xIIjxv20xvEc7CjxVAFwI0_ Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMI IF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUvYLPUUUUU = X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ From: Yu Kuai There are two BUG reports that raid5 will hang at bitmap_startwrite([1],[2]), root cause is that bitmap start write and end write is unbalanced, and while reviewing raid5 code, it's found that bitmap operations can be optimized. For example, for a 4 disks raid5, with chunksize=8k, if user issue a IO (0 + 48k) to the array: ┌────────────────────────────────────────────────────────────┐ │chunk 0 │ │ ┌────────────┬─────────────┬─────────────┬────────────┼ │ sh0 │A0: 0 + 4k │A1: 8k + 4k │A2: 16k + 4k │A3: P │ │ ┼────────────┼─────────────┼─────────────┼────────────┼ │ sh1 │B0: 4k + 4k │B1: 12k + 4k │B2: 20k + 4k │B3: P │ ┼──────┴────────────┴─────────────┴─────────────┴────────────┼ │chunk 1 │ │ ┌────────────┬─────────────┬─────────────┬────────────┤ │ sh2 │C0: 24k + 4k│C1: 32k + 4k │C2: P │C3: 40k + 4k│ │ ┼────────────┼─────────────┼─────────────┼────────────┼ │ sh3 │D0: 28k + 4k│D1: 36k + 4k │D2: P │D3: 44k + 4k│ └──────┴────────────┴─────────────┴─────────────┴────────────┘ Before this patch, 4 stripe head will be used, and each sh will attach bio for 3 disks, and each attached bio will trigger bitmap_startwrite() once, which means total 12 times. - 3 times (0 + 4k), for (A0, A1 and A2) - 3 times (4 + 4k), for (B0, B1 and B2) - 3 times (8 + 4k), for (C0, C1 and C3) - 3 times (12 + 4k), for (D0, D1 and D3) After this patch, md upper layer will calculate that IO range (0 + 48k) is corresponding to the bitmap (0 + 16k), and call bitmap_startwrite() just once. Noted that this patch will align bitmap ranges to the chunks, for example, if user issue a IO (0 + 4k) to array: - Before this patch, 1 time (0 + 4k), for A0; - After this patch, 1 time (0 + 8k) for chunk 0; Usually, one bitmap bit will represent more than one disk chunk, and this doesn't have any difference. And even if user really created a array that one chunk contain multiple bits, the overhead is that more data will be recovered after power failure. [1] https://lore.kernel.org/all/CAJpMwyjmHQLvm6zg1cmQErttNNQPDAAXPKM3xgTjMhbfts986Q@mail.gmail.com/ [2] https://lore.kernel.org/all/ADF7D720-5764-4AF3-B68E-1845988737AA@flyingcircus.io/ Signed-off-by: Yu Kuai --- drivers/md/md.c | 29 +++++++++++++++++++++++++++++ drivers/md/md.h | 2 ++ drivers/md/raid1.c | 4 ---- drivers/md/raid10.c | 3 --- drivers/md/raid5-cache.c | 2 -- drivers/md/raid5.c | 24 +----------------------- 6 files changed, 32 insertions(+), 32 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index bbe002ebd584..ab37c9939ac6 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -8723,12 +8723,32 @@ void md_submit_discard_bio(struct mddev *mddev, struct md_rdev *rdev, } EXPORT_SYMBOL_GPL(md_submit_discard_bio); +static void md_bitmap_start(struct mddev *mddev, + struct md_io_clone *md_io_clone) +{ + if (mddev->pers->bitmap_sector) + mddev->pers->bitmap_sector(mddev, &md_io_clone->offset, + &md_io_clone->sectors); + + mddev->bitmap_ops->startwrite(mddev, md_io_clone->offset, + md_io_clone->sectors); +} + +static void md_bitmap_end(struct mddev *mddev, struct md_io_clone *md_io_clone) +{ + mddev->bitmap_ops->endwrite(mddev, md_io_clone->offset, + md_io_clone->sectors); +} + static void md_end_clone_io(struct bio *bio) { struct md_io_clone *md_io_clone = bio->bi_private; struct bio *orig_bio = md_io_clone->orig_bio; struct mddev *mddev = md_io_clone->mddev; + if (bio_data_dir(orig_bio) == WRITE && mddev->bitmap) + md_bitmap_end(mddev, md_io_clone); + if (bio->bi_status && !orig_bio->bi_status) orig_bio->bi_status = bio->bi_status; @@ -8753,6 +8773,12 @@ static void md_clone_bio(struct mddev *mddev, struct bio **bio) if (blk_queue_io_stat(bdev->bd_disk->queue)) md_io_clone->start_time = bio_start_io_acct(*bio); + if (bio_data_dir(*bio) == WRITE && mddev->bitmap) { + md_io_clone->offset = (*bio)->bi_iter.bi_sector; + md_io_clone->sectors = bio_sectors(*bio); + md_bitmap_start(mddev, md_io_clone); + } + clone->bi_end_io = md_end_clone_io; clone->bi_private = md_io_clone; *bio = clone; @@ -8771,6 +8797,9 @@ void md_free_cloned_bio(struct bio *bio) struct bio *orig_bio = md_io_clone->orig_bio; struct mddev *mddev = md_io_clone->mddev; + if (bio_data_dir(orig_bio) == WRITE && mddev->bitmap) + md_bitmap_end(mddev, md_io_clone); + if (bio->bi_status && !orig_bio->bi_status) orig_bio->bi_status = bio->bi_status; diff --git a/drivers/md/md.h b/drivers/md/md.h index de6dadb9a40b..def808064ad8 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -831,6 +831,8 @@ struct md_io_clone { struct mddev *mddev; struct bio *orig_bio; unsigned long start_time; + sector_t offset; + unsigned long sectors; struct bio bio_clone; }; diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index b9819f9c8ed2..e2adfeff5ae6 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -422,8 +422,6 @@ static void close_write(struct r1bio *r1_bio) if (test_bit(R1BIO_BehindIO, &r1_bio->state)) mddev->bitmap_ops->end_behind_write(mddev); - /* clear the bitmap if all writes complete successfully */ - mddev->bitmap_ops->endwrite(mddev, r1_bio->sector, r1_bio->sectors); md_write_end(mddev); } @@ -1616,8 +1614,6 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, if (test_bit(R1BIO_BehindIO, &r1_bio->state)) mddev->bitmap_ops->start_behind_write(mddev); - mddev->bitmap_ops->startwrite(mddev, r1_bio->sector, - r1_bio->sectors); first_clone = 0; } diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index efbc0bd92479..79a209236c9f 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -428,8 +428,6 @@ static void close_write(struct r10bio *r10_bio) { struct mddev *mddev = r10_bio->mddev; - /* clear the bitmap if all writes complete successfully */ - mddev->bitmap_ops->endwrite(mddev, r10_bio->sector, r10_bio->sectors); md_write_end(mddev); } @@ -1487,7 +1485,6 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio, md_account_bio(mddev, &bio); r10_bio->master_bio = bio; atomic_set(&r10_bio->remaining, 1); - mddev->bitmap_ops->startwrite(mddev, r10_bio->sector, r10_bio->sectors); for (i = 0; i < conf->copies; i++) { if (r10_bio->devs[i].bio) diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c index ba4f9577c737..011246e16a99 100644 --- a/drivers/md/raid5-cache.c +++ b/drivers/md/raid5-cache.c @@ -313,8 +313,6 @@ void r5c_handle_cached_data_endio(struct r5conf *conf, if (sh->dev[i].written) { set_bit(R5_UPTODATE, &sh->dev[i].flags); r5c_return_dev_pending_writes(conf, &sh->dev[i]); - conf->mddev->bitmap_ops->endwrite(conf->mddev, - sh->sector, RAID5_STRIPE_SECTORS(conf)); } } } diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 95caed41654c..976788138a6e 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -3578,12 +3578,6 @@ static void __add_stripe_bio(struct stripe_head *sh, struct bio *bi, * is added to a batch, STRIPE_BIT_DELAY cannot be changed * any more. */ - set_bit(STRIPE_BITMAP_PENDING, &sh->state); - spin_unlock_irq(&sh->stripe_lock); - conf->mddev->bitmap_ops->startwrite(conf->mddev, sh->sector, - RAID5_STRIPE_SECTORS(conf)); - spin_lock_irq(&sh->stripe_lock); - clear_bit(STRIPE_BITMAP_PENDING, &sh->state); if (!sh->batch_head) { sh->bm_seq = conf->seq_flush+1; set_bit(STRIPE_BIT_DELAY, &sh->state); @@ -3638,7 +3632,6 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh, BUG_ON(sh->batch_head); for (i = disks; i--; ) { struct bio *bi; - int bitmap_end = 0; if (test_bit(R5_ReadError, &sh->dev[i].flags)) { struct md_rdev *rdev = conf->disks[i].rdev; @@ -3663,8 +3656,6 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh, sh->dev[i].towrite = NULL; sh->overwrite_disks = 0; spin_unlock_irq(&sh->stripe_lock); - if (bi) - bitmap_end = 1; log_stripe_write_finished(sh); @@ -3679,10 +3670,6 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh, bio_io_error(bi); bi = nextbi; } - if (bitmap_end) - conf->mddev->bitmap_ops->endwrite(conf->mddev, - sh->sector, RAID5_STRIPE_SECTORS(conf)); - bitmap_end = 0; /* and fail all 'written' */ bi = sh->dev[i].written; sh->dev[i].written = NULL; @@ -3691,7 +3678,6 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh, sh->dev[i].page = sh->dev[i].orig_page; } - if (bi) bitmap_end = 1; while (bi && bi->bi_iter.bi_sector < sh->dev[i].sector + RAID5_STRIPE_SECTORS(conf)) { struct bio *bi2 = r5_next_bio(conf, bi, sh->dev[i].sector); @@ -3725,9 +3711,6 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh, bi = nextbi; } } - if (bitmap_end) - conf->mddev->bitmap_ops->endwrite(conf->mddev, - sh->sector, RAID5_STRIPE_SECTORS(conf)); /* If we were in the middle of a write the parity block might * still be locked - so just clear all R5_LOCKED flags */ @@ -4076,8 +4059,7 @@ static void handle_stripe_clean_event(struct r5conf *conf, bio_endio(wbi); wbi = wbi2; } - conf->mddev->bitmap_ops->endwrite(conf->mddev, - sh->sector, RAID5_STRIPE_SECTORS(conf)); + if (head_sh->batch_head) { sh = list_first_entry(&sh->batch_list, struct stripe_head, @@ -5797,10 +5779,6 @@ static void make_discard_request(struct mddev *mddev, struct bio *bi) } spin_unlock_irq(&sh->stripe_lock); if (conf->mddev->bitmap) { - for (d = 0; d < conf->raid_disks - conf->max_degraded; - d++) - mddev->bitmap_ops->startwrite(mddev, sh->sector, - RAID5_STRIPE_SECTORS(conf)); sh->bm_seq = conf->seq_flush + 1; set_bit(STRIPE_BIT_DELAY, &sh->state); }