diff options
| author | Ming Lei <ming.lei@redhat.com> | 2022-03-05 05:08:04 +0300 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2022-03-09 20:21:56 +0300 |
| commit | b99fdcdc36369d2a3a26bf44736d420eb629d8b7 (patch) | |
| tree | e0f40de03f4b9264dba2de7201898a4782fe37c3 /drivers/md/dm-core.h | |
| parent | 69fe0f29892077f14b56e2a479b6bcf533209d53 (diff) | |
| download | linux-b99fdcdc36369d2a3a26bf44736d420eb629d8b7.tar.xz | |
dm: support bio polling
Support bio polling (REQ_POLLED) in the following approach:
1) only support io polling on normal READ/WRITE, and other abnormal IOs
still fallback to IRQ mode, so the target io (and DM's clone bio) is
exactly inside the dm io.
2) hold one refcnt on io->io_count after submitting this dm bio with
REQ_POLLED
3) support dm native bio splitting, any dm io instance associated with
current bio will be added into one list which head is bio->bi_private
which will be recovered before ending this bio
4) implement .poll_bio() callback, call bio_poll() on the single target
bio inside the dm io which is retrieved via bio->bi_bio_drv_data; call
dm_io_dec_pending() after the target io is done in .poll_bio()
5) enable QUEUE_FLAG_POLL if all underlying queues enable QUEUE_FLAG_POLL,
which is based on Jeffle's previous patch.
These changes are good for a 30-35% IOPS improvement for polled IO.
For detailed test results please see (Jens, thanks for testing!):
https://listman.redhat.com/archives/dm-devel/2022-March/049868.html
or https://marc.info/?l=linux-block&m=164684246214700&w=2
Tested-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md/dm-core.h')
| -rw-r--r-- | drivers/md/dm-core.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h index 8078b6c155ef..8cc03c0c262e 100644 --- a/drivers/md/dm-core.h +++ b/drivers/md/dm-core.h @@ -235,6 +235,8 @@ struct dm_io { bool start_io_acct:1; int was_accounted; unsigned long start_time; + void *data; + struct hlist_node node; spinlock_t endio_lock; struct dm_stats_aux stats_aux; /* last member of dm_target_io is 'struct bio' */ |