md/raid10: fix missing discard IO accounting

md_account_bio() is not called from raid10_handle_discard(), now that we
handle bitmap inside md_account_bio(), also fix missing
bitmap_startwrite for discard.

Test whole disk discard for 20G raid10:

Before:
Device   d/s     dMB/s   drqm/s  %drqm d_await dareq-sz
md0    48.00     16.00     0.00   0.00    5.42   341.33

After:
Device   d/s     dMB/s   drqm/s  %drqm d_await dareq-sz
md0    68.00  20462.00     0.00   0.00    2.65 308133.65

Link: https://lore.kernel.org/linux-raid/20250325015746.3195035-1-yukuai1@huaweicloud.com
Fixes: 528bc2cf2fcc ("md/raid10: enable io accounting")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Coly Li <colyli@kernel.org>
This commit is contained in:
Yu Kuai 2025-03-25 09:57:46 +08:00
parent 72070e57b0
commit d05af90d62

View File

@ -1735,6 +1735,7 @@ retry_discard:
* The discard bio returns only first r10bio finishes
*/
if (first_copy) {
md_account_bio(mddev, &bio);
r10_bio->master_bio = bio;
set_bit(R10BIO_Discard, &r10_bio->state);
first_copy = false;