On 12/25/21 12:28 AM, Vishal Verma wrote:
On 12/24/21 7:14 PM, Song Liu wrote:
On Tue, Dec 21, 2021 at 12:06 PM Vishal Verma<vverma@xxxxxxxxxxxxxxxx> wrote:
Returns EAGAIN in case the raid456 driver would block
waiting for situations like:
- Reshape operation,
- Discard operation.
Signed-off-by: Vishal Verma<vverma@xxxxxxxxxxxxxxxx>
I think we will need the following fix for raid456:
Ack
============================ 8< ============================
diff --git i/drivers/md/raid5.c w/drivers/md/raid5.c
index 6ab22f29dacd..55d372ce3300 100644
--- i/drivers/md/raid5.c
+++ w/drivers/md/raid5.c
@@ -5717,6 +5717,7 @@ static void make_discard_request(struct mddev
*mddev, struct bio *bi)
raid5_release_stripe(sh);
/* Bail out if REQ_NOWAIT is set */
if (bi->bi_opf & REQ_NOWAIT) {
+ finish_wait(&conf->wait_for_overlap, &w);
bio_wouldblock_error(bi);
return;
}
@@ -5734,6 +5735,7 @@ static void make_discard_request(struct mddev
*mddev, struct bio *bi)
raid5_release_stripe(sh);
/* Bail out if REQ_NOWAIT is set */
if (bi->bi_opf & REQ_NOWAIT) {
+
finish_wait(&conf->wait_for_overlap, &w);
bio_wouldblock_error(bi);
return;
}
@@ -5829,7 +5831,6 @@ static bool raid5_make_request(struct mddev
*mddev, struct bio * bi)
last_sector = bio_end_sector(bi);
bi->bi_next = NULL;
- md_account_bio(mddev, &bi);
/* Bail out if REQ_NOWAIT is set */
if ((bi->bi_opf & REQ_NOWAIT) &&
(conf->reshape_progress != MaxSector) &&
@@ -5837,9 +5838,11 @@ static bool raid5_make_request(struct mddev
*mddev, struct bio * bi)
? (logical_sector > conf->reshape_progress &&
logical_sector <= conf->reshape_safe)
: (logical_sector >= conf->reshape_safe && logical_sector
< conf->reshape_progress))) {
bio_wouldblock_error(bi);
+ if (rw == WRITE)
+ md_write_end(mddev);
return true;
}
-
+ 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;
============================ 8< ============================
Vishal, please try to trigger all these conditions (including raid1,
raid10) and make sure
they work properly.
For example, I triggered raid5 reshape and used something like the
following to make
sure the logic is triggered:
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 55d372ce3300..e79de48a0027 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -5840,6 +5840,11 @@ static bool raid5_make_request(struct mddev
*mddev, struct bio * bi)
bio_wouldblock_error(bi);
if (rw == WRITE)
md_write_end(mddev);
+ {
+ static int count = 0;
+ if (count++ < 10)
+ pr_info("%s REQ_NOWAIT return\n", __func__);
+ }
return true;
}
md_account_bio(mddev, &bi);
Thanks,
Song
Sure, will try this and verify for raid1/10.
I am running into an issue during raid10 reshape. I can see the nowait
code getting triggered during reshape, but it seems like the reshape
operation was stuck as soon as I issued write IO using FIO to the array
during reshape.
FIO also seem stuck i.e no IO went through...
