block: Don't poll in bdrv_replace_child_noperm()

In order to make sure that bdrv_replace_child_noperm() doesn't have to
poll any more, get rid of the bdrv_parent_drained_begin_single() call.

This is possible now because we can require that the parent is already
drained through the child in question when the function is called and we
don't call the parent drain callbacks more than once.

The additional drain calls needed in callers cause the test case to run
its code in the drain handler too early (bdrv_attach_child() drains
now), so modify it to only enable the code after the test setup has
completed.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221118174110.55183-15-kwolf@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c
index 172bc6d..2686a8a 100644
--- a/tests/unit/test-bdrv-drain.c
+++ b/tests/unit/test-bdrv-drain.c
@@ -1654,6 +1654,7 @@ static void test_drop_intermediate_poll(void)
 
 
 typedef struct BDRVReplaceTestState {
+    bool setup_completed;
     bool was_drained;
     bool was_undrained;
     bool has_read;
@@ -1738,6 +1739,10 @@ static void bdrv_replace_test_drain_begin(BlockDriverState *bs)
 {
     BDRVReplaceTestState *s = bs->opaque;
 
+    if (!s->setup_completed) {
+        return;
+    }
+
     if (!s->drain_count) {
         s->drain_co = qemu_coroutine_create(bdrv_replace_test_drain_co, bs);
         bdrv_inc_in_flight(bs);
@@ -1769,6 +1774,10 @@ static void bdrv_replace_test_drain_end(BlockDriverState *bs)
 {
     BDRVReplaceTestState *s = bs->opaque;
 
+    if (!s->setup_completed) {
+        return;
+    }
+
     g_assert(s->drain_count > 0);
     if (!--s->drain_count) {
         s->was_undrained = true;
@@ -1867,6 +1876,7 @@ static void do_test_replace_child_mid_drain(int old_drain_count,
     bdrv_ref(old_child_bs);
     bdrv_attach_child(parent_bs, old_child_bs, "child", &child_of_bds,
                       BDRV_CHILD_COW, &error_abort);
+    parent_s->setup_completed = true;
 
     for (i = 0; i < old_drain_count; i++) {
         bdrv_drained_begin(old_child_bs);