migration/block: compare only read blocks against the rate limiter

only read_done blocks are in the queued to be flushed to the migration
stream. submitted blocks are still in flight.
Signed-off-by: NPeter Lieven <pl@kamp.de>
Message-Id: <1520507908-16743-6-git-send-email-pl@kamp.de>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>

migration/block.c

@@ -773,8 +773,7 @@ static int block_save_iterate(QEMUFile *f, void *opaque)
 
     /* control the rate of transfer */
     blk_mig_lock();
-    while ((block_mig_state.submitted +
-            block_mig_state.read_done) * BLOCK_SIZE <
+    while (block_mig_state.read_done * BLOCK_SIZE <
            qemu_file_get_rate_limit(f) &&
            block_mig_state.submitted < MAX_PARALLEL_IO &&
            (block_mig_state.submitted + block_mig_state.read_done) <