Hi,
在 2025/8/30 8:41, Damien Le Moal 写道:
On 8/28/25 15:57, Yu Kuai wrote:
From: Yu Kuai <yukuai3@xxxxxxxxxx>
On the one hand unify bio split code, prepare to fix disordered split
IO; On the other hand fix missing blkcg_bio_issue_init() and
trace_block_split() for split IO.
Hmmm... Shouldn't that be a prep patch with a fixes tag for backport ?
Because that "fix" here is not done directly but is the result of calling
bio_submit_split_bioset().
I can add a fix tag as blkcg_bio_issue_init() and trace_block_split() is missed,
however, if we consider stable backport, should we fix this directly from caller
first? As this is better for backport. Later this patch can be just considered
cleanup.
Noted commit 319ff40a5427 ("md/raid0: Fix performance regression for large
sequential writes") already fix disordered split IO by converting bio to
underlying disks before submit_bio_noacct(), with the respect
md_submit_bio() already split by sectors, and raid0_make_request() will
split at most once for unaligned IO. This is a bit hacky and we'll convert
this to solution in general later.
Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
---
drivers/md/raid0.c | 19 +++++++------------
1 file changed, 7 insertions(+), 12 deletions(-)
diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index f1d8811a542a..4dcc5133d679 100644
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -463,21 +463,16 @@ static void raid0_handle_discard(struct mddev *mddev, struct bio *bio)
zone = find_zone(conf, &start);
if (bio_end_sector(bio) > zone->zone_end) {
- struct bio *split = bio_split(bio,
- zone->zone_end - bio->bi_iter.bi_sector, GFP_NOIO,
- &mddev->bio_set);
-
- if (IS_ERR(split)) {
- bio->bi_status = errno_to_blk_status(PTR_ERR(split));
- bio_endio(bio);
+ bio = bio_submit_split_bioset(bio,
+ zone->zone_end - bio->bi_iter.bi_sector,
Can this ever be negative (of course not I think)? But if
bio_submit_split_bioset() is changed to have an unsigned int sectors count,
maybe add a sanity check before calling bio_submit_split_bioset() ?
Yes, this can never be negative.
Thanks,
Kuai
+ &mddev->bio_set);
+ if (!bio)
return;
- }
- bio_chain(split, bio);
- submit_bio_noacct(bio);
- bio = split;
+
end = zone->zone_end;
- } else
+ } else {
end = bio_end_sector(bio);
+ }
orig_end = end;
if (zone != conf->strip_zone)
