md/raid5: add thread_group worker async_tx_issue_pending_all

commit 7e96d559634b73a8158ee99a7abece2eacec2668 upstream.

Since thread_group worker and raid5d kthread are not in sync, if
worker writes stripe before raid5d then requests will be waiting
for issue_pendig.

Issue observed when building raid5 with ext4, in some build runs
jbd2 would get hung and requests were waiting in the HW engine
waiting to be issued.

Fix this by adding a call to async_tx_issue_pending_all in the
raid5_do_work.

Signed-off-by: Ofer Heifetz <oferh@marvell.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 604c5dc95ffcd900e49f23b9b2af4bce696e77c1..094f36064ff015e3c47a1670c1fd543124a050ee 100644 (file)
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -5224,6 +5224,8 @@ static void raid5_do_work(struct work_struct *work)
        pr_debug("%d stripes handled\n", handled);
 
        spin_unlock_irq(&conf->device_lock);
+
+       async_tx_issue_pending_all();
        blk_finish_plug(&plug);
 
        pr_debug("--- raid5worker inactive\n");