6.14-stable review patch. If anyone has any objections, please let me know.
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From: Yu Kuai yukuai3@huawei.com
[ Upstream commit e879a0d9cb086c8e52ce6c04e5bfa63825a6213c ]
If blk-wbt is enabled by default, it's found that raid write performance is quite bad because all IO are throttled by wbt of underlying disks, due to flag REQ_IDLE is ignored. And turns out this behaviour exist since blk-wbt is introduced.
Other than REQ_IDLE, other flags should not be ignored as well, for example REQ_META can be set for filesystems, clearing it can cause priority reverse problems; And REQ_NOWAIT should not be cleared as well, because io will wait instead of failing directly in underlying disks.
Fix those problems by keep IO flags from master bio.
Fises: f51d46d0e7cb ("md: add support for REQ_NOWAIT") Fixes: e34cbd307477 ("blk-wbt: add general throttling mechanism") Fixes: 5404bc7a87b9 ("[PATCH] Allow file systems to differentiate between data and meta reads") Link: https://lore.kernel.org/linux-raid/20250227121657.832356-1-yukuai1@huaweiclo... Signed-off-by: Yu Kuai yukuai3@huawei.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/raid1.c | 5 ----- drivers/md/raid10.c | 8 -------- 2 files changed, 13 deletions(-)
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index cb108b3e28c4d..44dcfebff4f03 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1316,8 +1316,6 @@ static void raid1_read_request(struct mddev *mddev, struct bio *bio, struct r1conf *conf = mddev->private; struct raid1_info *mirror; struct bio *read_bio; - const enum req_op op = bio_op(bio); - const blk_opf_t do_sync = bio->bi_opf & REQ_SYNC; int max_sectors; int rdisk, error; bool r1bio_existed = !!r1_bio; @@ -1405,7 +1403,6 @@ static void raid1_read_request(struct mddev *mddev, struct bio *bio, read_bio->bi_iter.bi_sector = r1_bio->sector + mirror->rdev->data_offset; read_bio->bi_end_io = raid1_end_read_request; - read_bio->bi_opf = op | do_sync; if (test_bit(FailFast, &mirror->rdev->flags) && test_bit(R1BIO_FailFast, &r1_bio->state)) read_bio->bi_opf |= MD_FAILFAST; @@ -1654,8 +1651,6 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio,
mbio->bi_iter.bi_sector = (r1_bio->sector + rdev->data_offset); mbio->bi_end_io = raid1_end_write_request; - mbio->bi_opf = bio_op(bio) | - (bio->bi_opf & (REQ_SYNC | REQ_FUA | REQ_ATOMIC)); if (test_bit(FailFast, &rdev->flags) && !test_bit(WriteMostly, &rdev->flags) && conf->raid_disks - mddev->degraded > 1) diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 15b9ae5bf84d8..c897b19dc2d53 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -1146,8 +1146,6 @@ static void raid10_read_request(struct mddev *mddev, struct bio *bio, { struct r10conf *conf = mddev->private; struct bio *read_bio; - const enum req_op op = bio_op(bio); - const blk_opf_t do_sync = bio->bi_opf & REQ_SYNC; int max_sectors; struct md_rdev *rdev; char b[BDEVNAME_SIZE]; @@ -1228,7 +1226,6 @@ static void raid10_read_request(struct mddev *mddev, struct bio *bio, read_bio->bi_iter.bi_sector = r10_bio->devs[slot].addr + choose_data_offset(r10_bio, rdev); read_bio->bi_end_io = raid10_end_read_request; - read_bio->bi_opf = op | do_sync; if (test_bit(FailFast, &rdev->flags) && test_bit(R10BIO_FailFast, &r10_bio->state)) read_bio->bi_opf |= MD_FAILFAST; @@ -1247,10 +1244,6 @@ static void raid10_write_one_disk(struct mddev *mddev, struct r10bio *r10_bio, struct bio *bio, bool replacement, int n_copy) { - const enum req_op op = bio_op(bio); - const blk_opf_t do_sync = bio->bi_opf & REQ_SYNC; - const blk_opf_t do_fua = bio->bi_opf & REQ_FUA; - const blk_opf_t do_atomic = bio->bi_opf & REQ_ATOMIC; unsigned long flags; struct r10conf *conf = mddev->private; struct md_rdev *rdev; @@ -1269,7 +1262,6 @@ static void raid10_write_one_disk(struct mddev *mddev, struct r10bio *r10_bio, mbio->bi_iter.bi_sector = (r10_bio->devs[n_copy].addr + choose_data_offset(r10_bio, rdev)); mbio->bi_end_io = raid10_end_write_request; - mbio->bi_opf = op | do_sync | do_fua | do_atomic; if (!replacement && test_bit(FailFast, &conf->mirrors[devnum].rdev->flags) && enough(conf, devnum))