test-bdrv-drain: Test node deletion in subtree recursion

If bdrv_do_drained_begin() polls during its subtree recursion, the graph
can change and mess up the bs->children iteration. Test that this
doesn't happen.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2018-03-23 12:40:21 +01:00
parent fe4f0614ef
commit ebd3183761

View File

@ -880,7 +880,8 @@ static void coroutine_fn test_co_delete_by_drain(void *opaque)
* If @detach_instead_of_delete is set, the BDS is not going to be
* deleted but will only detach all of its children.
*/
static void do_test_delete_by_drain(bool detach_instead_of_delete)
static void do_test_delete_by_drain(bool detach_instead_of_delete,
enum drain_type drain_type)
{
BlockBackend *blk;
BlockDriverState *bs, *child_bs, *null_bs;
@ -936,9 +937,23 @@ static void do_test_delete_by_drain(bool detach_instead_of_delete)
* test_co_delete_by_drain() resuming. Thus, @bs will be deleted
* and the coroutine will exit while this drain operation is still
* in progress. */
bdrv_ref(child_bs);
bdrv_drain(child_bs);
bdrv_unref(child_bs);
switch (drain_type) {
case BDRV_DRAIN:
bdrv_ref(child_bs);
bdrv_drain(child_bs);
bdrv_unref(child_bs);
break;
case BDRV_SUBTREE_DRAIN:
/* Would have to ref/unref bs here for !detach_instead_of_delete, but
* then the whole test becomes pointless because the graph changes
* don't occur during the drain any more. */
assert(detach_instead_of_delete);
bdrv_subtree_drained_begin(bs);
bdrv_subtree_drained_end(bs);
break;
default:
g_assert_not_reached();
}
while (!dbdd.done) {
aio_poll(qemu_get_aio_context(), true);
@ -951,15 +966,19 @@ static void do_test_delete_by_drain(bool detach_instead_of_delete)
}
}
static void test_delete_by_drain(void)
{
do_test_delete_by_drain(false);
do_test_delete_by_drain(false, BDRV_DRAIN);
}
static void test_detach_by_drain(void)
{
do_test_delete_by_drain(true);
do_test_delete_by_drain(true, BDRV_DRAIN);
}
static void test_detach_by_drain_subtree(void)
{
do_test_delete_by_drain(true, BDRV_SUBTREE_DRAIN);
}
@ -1010,8 +1029,9 @@ int main(int argc, char **argv)
g_test_add_func("/bdrv-drain/blockjob/drain_subtree",
test_blockjob_drain_subtree);
g_test_add_func("/bdrv-drain/deletion", test_delete_by_drain);
g_test_add_func("/bdrv-drain/detach", test_detach_by_drain);
g_test_add_func("/bdrv-drain/deletion/drain", test_delete_by_drain);
g_test_add_func("/bdrv-drain/detach/drain", test_detach_by_drain);
g_test_add_func("/bdrv-drain/detach/drain_subtree", test_detach_by_drain_subtree);
ret = g_test_run();
qemu_event_destroy(&done_event);