[PATCH 3.2 042/115] raid10: include bio_end_io_list in nr_queued to prevent freeze_array hang

From: Ben Hutchings
Date: Tue Apr 26 2016 - 19:20:13 EST


3.2.80-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Shaohua Li <shli@xxxxxx>

commit 23ddba80ebe836476bb2fa1f5ef305dd1c63dc0b upstream.

This is the raid10 counterpart of the bug fixed by Nate
(raid1: include bio_end_io_list in nr_queued to prevent freeze_array hang)

Fixes: 95af587e95(md/raid10: ensure device failure recorded before write request returns)
Cc: Nate Dailey <nate.dailey@xxxxxxxxxxx>
Signed-off-by: Shaohua Li <shli@xxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/md/raid10.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -2241,6 +2241,7 @@ static void handle_write_completed(struc
if (fail) {
spin_lock_irq(&conf->device_lock);
list_add(&r10_bio->retry_list, &conf->bio_end_io_list);
+ conf->nr_queued++;
spin_unlock_irq(&conf->device_lock);
md_wakeup_thread(conf->mddev->thread);
} else {
@@ -2267,8 +2268,10 @@ static void raid10d(struct mddev *mddev)
LIST_HEAD(tmp);
spin_lock_irqsave(&conf->device_lock, flags);
if (!test_bit(MD_CHANGE_PENDING, &mddev->flags)) {
- list_add(&tmp, &conf->bio_end_io_list);
- list_del_init(&conf->bio_end_io_list);
+ while (!list_empty(&conf->bio_end_io_list)) {
+ list_move(conf->bio_end_io_list.prev, &tmp);
+ conf->nr_queued--;
+ }
}
spin_unlock_irqrestore(&conf->device_lock, flags);
while (!list_empty(&tmp)) {