drbd: report congestion if we are waiting for some userland callback
If the drbd worker thread is synchronously waiting for some userland
callback, we don't want some casual pageout to block on us.
Have drbd_congested() report congestion in that case.
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_nl.c b/drivers/block/drbd/drbd_nl.c
index 40a1c4f0..03fc853 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -147,6 +147,9 @@
char *argv[] = {usermode_helper, cmd, mb, NULL };
int ret;
+ if (current == mdev->worker.task)
+ set_bit(CALLBACK_PENDING, &mdev->flags);
+
snprintf(mb, 12, "minor-%d", mdev_to_minor(mdev));
if (get_net_conf(mdev)) {
@@ -189,6 +192,9 @@
usermode_helper, cmd, mb,
(ret >> 8) & 0xff, ret);
+ if (current == mdev->worker.task)
+ clear_bit(CALLBACK_PENDING, &mdev->flags);
+
if (ret < 0) /* Ignore any ERRNOs we got. */
ret = 0;
