[PATCH 3.10 065/139] md/raid10: submit bio directly to replacement disk

From: Willy Tarreau
Date: Wed Nov 01 2017 - 17:48:30 EST


From: Shaohua Li <shli@xxxxxx>

commit 6d399783e9d4e9bd44931501948059d24ad96ff8 upstream.

Commit 57c67df(md/raid10: submit IO from originating thread instead of
md thread) submits bio directly for normal disks but not for replacement
disks. There is no point we shouldn't do this for replacement disks.

Cc: NeilBrown <neilb@xxxxxxxx>
Signed-off-by: Shaohua Li <shli@xxxxxx>
Signed-off-by: Willy Tarreau <w@xxxxxx>
---
drivers/md/raid10.c | 19 ++++++++++++++++---
1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index f53f4f8..b4de9c3 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1569,11 +1569,24 @@ retry_write:
mbio->bi_private = r10_bio;

atomic_inc(&r10_bio->remaining);
+
+ cb = blk_check_plugged(raid10_unplug, mddev,
+ sizeof(*plug));
+ if (cb)
+ plug = container_of(cb, struct raid10_plug_cb,
+ cb);
+ else
+ plug = NULL;
spin_lock_irqsave(&conf->device_lock, flags);
- bio_list_add(&conf->pending_bio_list, mbio);
- conf->pending_count++;
+ if (plug) {
+ bio_list_add(&plug->pending, mbio);
+ plug->pending_cnt++;
+ } else {
+ bio_list_add(&conf->pending_bio_list, mbio);
+ conf->pending_count++;
+ }
spin_unlock_irqrestore(&conf->device_lock, flags);
- if (!mddev_check_plugged(mddev))
+ if (!plug)
md_wakeup_thread(mddev->thread);
}
}
--
2.8.0.rc2.1.gbe9624a