drbd: flush drbd work queue before invalidate/invalidate remote
If you do back to back wait-sync/invalidate on a Primary in a tight loop,
during application IO load, you could trigger a race:
kernel: block drbd6: FIXME going to queue 'set_n_write from StartingSync'
but 'write from resync_finished' still pending?
Fix this by changing the order of the drbd_queue_work() and
the wake_up() in dec_ap_pending(), and adding the additional
drbd_flush_workqueue() before requesting the full sync.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 5136510..2704af2 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -2421,15 +2421,17 @@
int ap_bio = atomic_dec_return(&mdev->ap_bio_cnt);
D_ASSERT(ap_bio >= 0);
+
+ if (ap_bio == 0 && test_bit(BITMAP_IO, &mdev->flags)) {
+ if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags))
+ drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w);
+ }
+
/* this currently does wake_up for every dec_ap_bio!
* maybe rather introduce some type of hysteresis?
* e.g. (ap_bio == mxb/2 || ap_bio == 0) ? */
if (ap_bio < mxb)
wake_up(&mdev->misc_wait);
- if (ap_bio == 0 && test_bit(BITMAP_IO, &mdev->flags)) {
- if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags))
- drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w);
- }
}
static inline int drbd_set_ed_uuid(struct drbd_conf *mdev, u64 val)
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index a68d9bf..c47df7c 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -1977,9 +1977,11 @@
int retcode;
/* If there is still bitmap IO pending, probably because of a previous
- * resync just being finished, wait for it before requesting a new resync. */
+ * resync just being finished, wait for it before requesting a new resync.
+ * Also wait for it's after_state_ch(). */
drbd_suspend_io(mdev);
wait_event(mdev->misc_wait, !test_bit(BITMAP_IO, &mdev->flags));
+ drbd_flush_workqueue(mdev);
retcode = _drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T), CS_ORDERED);
@@ -2018,9 +2020,11 @@
int retcode;
/* If there is still bitmap IO pending, probably because of a previous
- * resync just being finished, wait for it before requesting a new resync. */
+ * resync just being finished, wait for it before requesting a new resync.
+ * Also wait for it's after_state_ch(). */
drbd_suspend_io(mdev);
wait_event(mdev->misc_wait, !test_bit(BITMAP_IO, &mdev->flags));
+ drbd_flush_workqueue(mdev);
retcode = _drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_S), CS_ORDERED);
