[Qemu-devel] [PULL 76/93] block: write: Handle COR dependency after I/O throttling

[Kevin Wolf <kwolf@redhat.com>]

First waiting for all COR requests to complete and calling the
throttling function afterwards means that the request could be delayed
and we still need to wait for the COR request even if it was issued only
after the throttled write request.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
---
 block.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/block.c b/block.c
index d9c472b..20a3853 100644
--- a/block.c
+++ b/block.c
@@ -3159,6 +3159,10 @@ static int coroutine_fn bdrv_aligned_pwritev(BlockDriverState *bs,
     assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0);
     assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0);
 
+    if (bs->copy_on_read_in_flight) {
+        wait_for_overlapping_requests(bs, sector_num, nb_sectors);
+    }
+
     tracked_request_begin(&req, bs, sector_num, nb_sectors, true);
 
     ret = notifier_with_return_list_notify(&bs->before_write_notifiers, &req);
@@ -3208,10 +3212,6 @@ static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs,
         return -EIO;
     }
 
-    if (bs->copy_on_read_in_flight) {
-        wait_for_overlapping_requests(bs, sector_num, nb_sectors);
-    }
-
     /* throttling disk I/O */
     if (bs->io_limits_enabled) {
         bdrv_io_limits_intercept(bs, nb_sectors, true);
-- 
1.8.1.4