md/raid10: submit bio directly to replacement disk

[ Upstream commit 6d399783e9d4e9bd44931501948059d24ad96ff8 ]

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@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 4c4aab02e3116a350b0f0a3c09c72efa29e5f087..b19b551bb34bbf3da6b9ab9c4a0af69de71488b3 100644 (file)
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1407,11 +1407,24 @@ 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);
                }
        }