Re: [PATCH] tests/qtest: failover: fix infinite loop

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Laurent Vivier (lvivier@redhat.com) wrote:
> If the migration is over before we cancel it, we are
> waiting in a loop a state that never comes because the state
> is already "completed".
> 
> To avoid an infinite loop, skip the test if the migration
> is "completed" before we were able to cancel it.
> 
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>

If you're finding it's skipping to often, you might try setting the
migration bandwidth really low right at the start (a few bytes/second)
to ensure it doesn't complete under your feet.

Dave

> ---
>  tests/qtest/virtio-net-failover.c | 29 +++++++++++++++++++++++++----
>  1 file changed, 25 insertions(+), 4 deletions(-)
> 
> diff --git a/tests/qtest/virtio-net-failover.c b/tests/qtest/virtio-net-failover.c
> index 80292eecf65f..78811f1c9216 100644
> --- a/tests/qtest/virtio-net-failover.c
> +++ b/tests/qtest/virtio-net-failover.c
> @@ -1141,6 +1141,11 @@ static void test_migrate_guest_off_abort(gconstpointer opaque)
>          ret = migrate_status(qts);
>  
>          status = qdict_get_str(ret, "status");
> +        if (strcmp(status, "completed") == 0) {
> +            g_test_skip("Failed to cancel the migration");
> +            qobject_unref(ret);
> +            goto out;
> +        }
>          if (strcmp(status, "active") == 0) {
>              qobject_unref(ret);
>              break;
> @@ -1155,8 +1160,12 @@ static void test_migrate_guest_off_abort(gconstpointer opaque)
>  
>      while (true) {
>          ret = migrate_status(qts);
> -
>          status = qdict_get_str(ret, "status");
> +        if (strcmp(status, "completed") == 0) {
> +            g_test_skip("Failed to cancel the migration");
> +            qobject_unref(ret);
> +            goto out;
> +        }
>          if (strcmp(status, "cancelled") == 0) {
>              qobject_unref(ret);
>              break;
> @@ -1169,6 +1178,7 @@ static void test_migrate_guest_off_abort(gconstpointer opaque)
>      check_one_card(qts, true, "standby0", MAC_STANDBY0);
>      check_one_card(qts, false, "primary0", MAC_PRIMARY0);
>  
> +out:
>      qos_object_destroy((QOSGraphObject *)vdev);
>      machine_stop(qts);
>  }
> @@ -1251,8 +1261,7 @@ static void test_migrate_abort_wait_unplug(gconstpointer opaque)
>              qobject_unref(ret);
>              break;
>          }
> -        g_assert_cmpstr(status, !=, "failed");
> -        g_assert_cmpstr(status, !=, "active");
> +        g_assert_cmpstr(status, ==, "cancelling");
>          qobject_unref(ret);
>      }
>  
> @@ -1324,11 +1333,11 @@ static void test_migrate_abort_active(gconstpointer opaque)
>          ret = migrate_status(qts);
>  
>          status = qdict_get_str(ret, "status");
> +        g_assert_cmpstr(status, !=, "failed");
>          if (strcmp(status, "wait-unplug") != 0) {
>              qobject_unref(ret);
>              break;
>          }
> -        g_assert_cmpstr(status, !=, "failed");
>          qobject_unref(ret);
>      }
>  
> @@ -1340,6 +1349,11 @@ static void test_migrate_abort_active(gconstpointer opaque)
>          ret = migrate_status(qts);
>  
>          status = qdict_get_str(ret, "status");
> +        if (strcmp(status, "completed") == 0) {
> +            g_test_skip("Failed to cancel the migration");
> +            qobject_unref(ret);
> +            goto out;
> +        }
>          if (strcmp(status, "cancelled") == 0) {
>              qobject_unref(ret);
>              break;
> @@ -1352,6 +1366,7 @@ static void test_migrate_abort_active(gconstpointer opaque)
>      check_one_card(qts, true, "standby0", MAC_STANDBY0);
>      check_one_card(qts, true, "primary0", MAC_PRIMARY0);
>  
> +out:
>      qos_object_destroy((QOSGraphObject *)vdev);
>      machine_stop(qts);
>  }
> @@ -1425,6 +1440,11 @@ static void test_migrate_off_abort(gconstpointer opaque)
>          ret = migrate_status(qts);
>  
>          status = qdict_get_str(ret, "status");
> +        if (strcmp(status, "completed") == 0) {
> +            g_test_skip("Failed to cancel the migration");
> +            qobject_unref(ret);
> +            goto out;
> +        }
>          if (strcmp(status, "cancelled") == 0) {
>              qobject_unref(ret);
>              break;
> @@ -1437,6 +1457,7 @@ static void test_migrate_off_abort(gconstpointer opaque)
>      check_one_card(qts, true, "standby0", MAC_STANDBY0);
>      check_one_card(qts, true, "primary0", MAC_PRIMARY0);
>  
> +out:
>      qos_object_destroy((QOSGraphObject *)vdev);
>      machine_stop(qts);
>  }
> -- 
> 2.35.1
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK