Messages in this thread Patch in this message | | | From | Philipp Reisner <> | Subject | [PATCH 32/38] drbd: don't block forever in disconnect during resync if fencing=r-a-stonith | Date | Wed, 25 Nov 2015 11:54:05 +0100 |
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From: Lars Ellenberg <lars.ellenberg@linbit.com>
Disconnect should wait for pending bitmap IO. But if that bitmap IO is not happening, because it is waiting for pending application IO, and there is no progress, because the fencing policy suspended application IO because of the disconnect, then we deadlock.
The bitmap writeout in this case does not care for concurrent application IO, so there is no point waiting for it.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com> --- drivers/block/drbd/drbd_main.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 136fa73..5b43dfb 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -3563,7 +3563,9 @@ void drbd_queue_bitmap_io(struct drbd_device *device, spin_lock_irq(&device->resource->req_lock); set_bit(BITMAP_IO, &device->flags); - if (atomic_read(&device->ap_bio_cnt) == 0) { + /* don't wait for pending application IO if the caller indicates that + * application IO does not conflict anyways. */ + if (flags == BM_LOCKED_CHANGE_ALLOWED || atomic_read(&device->ap_bio_cnt) == 0) { if (!test_and_set_bit(BITMAP_IO_QUEUED, &device->flags)) drbd_queue_work(&first_peer_device(device)->connection->sender_work, &device->bm_io_work.w); -- 1.9.1
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