Re: [PATCH v1 11/15] tests/qtest/migration: Use defer for cpr-tests

[Peter Xu <peterx@redhat.com>]

On Tue, May 05, 2026 at 01:09:10PM -0300, Fabiano Rosas wrote:
> Signed-off-by: Fabiano Rosas <farosas@suse.de>
> ---
>  tests/qtest/migration/cpr-tests.c | 21 ++++++++++++---------

Reviewed-by: Peter Xu <peterx@redhat.com>

Only one thing to double check:

>  1 file changed, 12 insertions(+), 9 deletions(-)
> 
> diff --git a/tests/qtest/migration/cpr-tests.c b/tests/qtest/migration/cpr-tests.c
> index 18217f0460..9091a84213 100644
> --- a/tests/qtest/migration/cpr-tests.c
> +++ b/tests/qtest/migration/cpr-tests.c
> @@ -60,7 +60,7 @@ static int test_transfer(MigrateCommon *args, const char *cpr_channel,
>      obj = migrate_str_to_channel(cpr_channel);
>      qlist_append(channels_list, obj);
>  
> -    if (migrate_start(&from, &to, args->listen_uri, &args->start)) {
> +    if (migrate_start(&from, &to, "defer", &args->start)) {
>          return -1;
>      }
>  
> @@ -128,11 +128,17 @@ static void test_mode_transfer_common(MigrateCommon *args, bool incoming_defer)
>      int cpr_sockfd = qtest_socket_server(cpr_path);
>      g_assert(cpr_sockfd >= 0);
>  
> -    opts_target = g_strdup_printf("-incoming cpr,addr.transport=socket,"
> -                                  "addr.type=fd,addr.str=%d %s",
> -                                  cpr_sockfd, opts);
> +    if (incoming_defer) {
> +        opts_target = g_strdup_printf("-incoming cpr,addr.transport=socket,"
> +                                      "addr.type=fd,addr.str=%d %s",
> +                                      cpr_sockfd, opts);
> +    } else {
> +        opts_target = g_strdup_printf("-incoming %s "
> +                                      "-incoming cpr,addr.transport=socket,"
> +                                      "addr.type=fd,addr.str=%d %s",
> +                                      uri, cpr_sockfd, opts);

IIUC now in this path qtest will ultimately generate cmdline like this for
dest:

  -incoming defer \
  -incoming unix:... \
  -incoming cpr,addr...

I am not sure if this is the intention, but it looks working indeed where
the 1st defer will be an no-op, and "-incoming" allows overwrites.

We'll just need to remember this and be careful in the future on the order
of these parameters. Say, if we accidentally move the first "-incoming
defer" parameter to be after opts_target, then it might break, because then
it's not no-op anymore but freeing the main channel we just set.

But I think it's ok for now.

> +    }
>  
> -    args->listen_uri = incoming_defer ? "defer" : uri;
>      args->connect_channels = connect_channels;
>  
>      args->start.opts_source = opts;
> @@ -224,7 +230,7 @@ static void test_cpr_exec(MigrateCommon *args)
>      g_autofree char *filename = g_strdup_printf("%s/%s", tmpfs,
>                                                  FILE_TEST_FILENAME);
>  
> -    if (migrate_start(&from, NULL, args->listen_uri, &args->start)) {
> +    if (migrate_start(&from, NULL, "defer", &args->start)) {
>          return;
>      }
>  
> @@ -274,10 +280,7 @@ static void test_mode_exec(char *name, MigrateCommon *args)
>  {
>      g_autofree char *uri = g_strdup_printf("file:%s/%s", tmpfs,
>                                             FILE_TEST_FILENAME);
> -    g_autofree char *listen_uri = g_strdup_printf("defer");
> -
>      args->connect_uri = uri;
> -    args->listen_uri = listen_uri;
>      args->start_hook = test_mode_exec_start;
>  
>      args->start.only_source = true;
> -- 
> 2.51.0
> 

-- 
Peter Xu