[PATCH 01/30] drbd: bitmap bulk IO: do not always suspend IO

From: Philipp Reisner
Date: Mon Apr 25 2016 - 08:16:53 EST


From: Lars Ellenberg <lars.ellenberg@xxxxxxxxxx>

The intention was to only suspend IO if some normal bitmap operation is
supposed to be locked out, not always. If the bulk operation is flaged
as BM_LOCKED_CHANGE_ALLOWED, we do not need to suspend IO.

Signed-off-by: Philipp Reisner <philipp.reisner@xxxxxxxxxx>
Signed-off-by: Lars Ellenberg <lars.ellenberg@xxxxxxxxxx>
---
drivers/block/drbd/drbd_main.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index fa20977..802d729 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -3585,18 +3585,20 @@ void drbd_queue_bitmap_io(struct drbd_device *device,
int drbd_bitmap_io(struct drbd_device *device, int (*io_fn)(struct drbd_device *),
char *why, enum bm_flag flags)
{
+ /* Only suspend io, if some operation is supposed to be locked out */
+ const bool do_suspend_io = flags & (BM_DONT_CLEAR|BM_DONT_SET|BM_DONT_TEST);
int rv;

D_ASSERT(device, current != first_peer_device(device)->connection->worker.task);

- if ((flags & BM_LOCKED_SET_ALLOWED) == 0)
+ if (do_suspend_io)
drbd_suspend_io(device);

drbd_bm_lock(device, why, flags);
rv = io_fn(device);
drbd_bm_unlock(device);

- if ((flags & BM_LOCKED_SET_ALLOWED) == 0)
+ if (do_suspend_io)
drbd_resume_io(device);

return rv;
--
1.9.1