From 1147f58e1010b8688bac1fd3bbab753b1379291d Mon Sep 17 00:00:00 2001 From: Guoqing Jiang Date: Tue, 25 May 2021 17:46:19 +0800 Subject: [PATCH] md/raid5: avoid redundant bio clone in raid5_read_one_chunk After enable io accounting, chunk read bio could be cloned twice which is not good. To avoid such inefficiency, let's clone align_bio from io_acct_set too, then we need only call md_account_bio in make_request unconditionally. Signed-off-by: Guoqing Jiang Signed-off-by: Song Liu --- drivers/md/raid5.c | 29 +++++++++++++++-------------- 1 file changed, 15 insertions(+), 14 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 5a05277f4be7..f83623ac8c34 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -5364,11 +5364,13 @@ static struct bio *remove_bio_from_retry(struct r5conf *conf, */ static void raid5_align_endio(struct bio *bi) { - struct bio* raid_bi = bi->bi_private; + struct md_io_acct *md_io_acct = bi->bi_private; + struct bio *raid_bi = md_io_acct->orig_bio; struct mddev *mddev; struct r5conf *conf; struct md_rdev *rdev; blk_status_t error = bi->bi_status; + unsigned long start_time = md_io_acct->start_time; bio_put(bi); @@ -5380,6 +5382,8 @@ static void raid5_align_endio(struct bio *bi) rdev_dec_pending(rdev, conf->mddev); if (!error) { + if (blk_queue_io_stat(raid_bi->bi_bdev->bd_disk->queue)) + bio_end_io_acct(raid_bi, start_time); bio_endio(raid_bi); if (atomic_dec_and_test(&conf->active_aligned_reads)) wake_up(&conf->wait_for_quiescent); @@ -5398,6 +5402,7 @@ static int raid5_read_one_chunk(struct mddev *mddev, struct bio *raid_bio) struct md_rdev *rdev; sector_t sector, end_sector, first_bad; int bad_sectors, dd_idx; + struct md_io_acct *md_io_acct; if (!in_chunk_boundary(mddev, raid_bio)) { pr_debug("%s: non aligned\n", __func__); @@ -5434,14 +5439,18 @@ static int raid5_read_one_chunk(struct mddev *mddev, struct bio *raid_bio) return 0; } - align_bio = bio_clone_fast(raid_bio, GFP_NOIO, &mddev->bio_set); + align_bio = bio_clone_fast(raid_bio, GFP_NOIO, &mddev->io_acct_set); + md_io_acct = container_of(align_bio, struct md_io_acct, bio_clone); + raid_bio->bi_next = (void *)rdev; + if (blk_queue_io_stat(raid_bio->bi_bdev->bd_disk->queue)) + md_io_acct->start_time = bio_start_io_acct(raid_bio); + md_io_acct->orig_bio = raid_bio; + bio_set_dev(align_bio, rdev->bdev); align_bio->bi_end_io = raid5_align_endio; - align_bio->bi_private = raid_bio; + align_bio->bi_private = md_io_acct; align_bio->bi_iter.bi_sector = sector; - raid_bio->bi_next = (void *)rdev; - /* No reshape active, so we can trust rdev->data_offset */ align_bio->bi_iter.bi_sector += rdev->data_offset; @@ -5468,7 +5477,6 @@ static struct bio *chunk_aligned_read(struct mddev *mddev, struct bio *raid_bio) sector_t sector = raid_bio->bi_iter.bi_sector; unsigned chunk_sects = mddev->chunk_sectors; unsigned sectors = chunk_sects - (sector & (chunk_sects-1)); - struct r5conf *conf = mddev->private; if (sectors < bio_sectors(raid_bio)) { struct r5conf *conf = mddev->private; @@ -5478,9 +5486,6 @@ static struct bio *chunk_aligned_read(struct mddev *mddev, struct bio *raid_bio) raid_bio = split; } - if (raid_bio->bi_pool != &conf->bio_split) - md_account_bio(mddev, &raid_bio); - if (!raid5_read_one_chunk(mddev, raid_bio)) return raid_bio; @@ -5760,7 +5765,6 @@ static bool raid5_make_request(struct mddev *mddev, struct bio * bi) DEFINE_WAIT(w); bool do_prepare; bool do_flush = false; - bool do_clone = false; if (unlikely(bi->bi_opf & REQ_PREFLUSH)) { int ret = log_handle_flush_request(conf, bi); @@ -5789,7 +5793,6 @@ static bool raid5_make_request(struct mddev *mddev, struct bio * bi) if (rw == READ && mddev->degraded == 0 && mddev->reshape_position == MaxSector) { bi = chunk_aligned_read(mddev, bi); - do_clone = true; if (!bi) return true; } @@ -5804,9 +5807,7 @@ static bool raid5_make_request(struct mddev *mddev, struct bio * bi) last_sector = bio_end_sector(bi); bi->bi_next = NULL; - if (!do_clone) - md_account_bio(mddev, &bi); - + md_account_bio(mddev, &bi); prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE); for (; logical_sector < last_sector; logical_sector += RAID5_STRIPE_SECTORS(conf)) { int previous;