[PATCH 20/26] qtest/migration-tests.c: use "-incoming defer" for postcopy tests

From: Wei Wang <wei.w.wang(a)intel.com&gt; The Postcopy preempt capability is expected to be set before incoming starts, so change the postcopy tests to start with deferred incoming and call migrate-incoming after the cap has been set. Why the existing tests (without this patch) didn't fail? There could be two reasons: 1) "backlog" specifies the number of pending connections. As long as the server accepts the connections faster than the clients side connecting, connection will succeed. For the preempt test, it uses only 2 channels, so very likely to not have pending connections. 2) per my tests (on kernel 6.2), the number of pending connections allowed is actually "backlog + 1", which is 2 in this case. That said, the implementation of socket_start_incoming_migration_internal expects "migrate defer" to be used, and for safety, change the test to work with the expected usage. Signed-off-by: Wei Wang <wei.w.wang(a)intel.com&gt; Reviewed-by: Peter Xu <peterx(a)redhat.com&gt; Reviewed-by: Juan Quintela <quintela(a)redhat.com&gt; Message-ID: <20230606101910.20456-3-wei.w.wang(a)intel.com&gt; Signed-off-by: Juan Quintela <quintela(a)redhat.com&gt; --- tests/qtest/migration-test.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/tests/qtest/migration-test.c b/tests/qtest/migration-test.c index fd145e38d9..62d3f37021 100644 --- a/tests/qtest/migration-test.c +++ b/tests/qtest/migration-test.c @@ -1239,10 +1239,9 @@ static int migrate_postcopy_prepare(QTestState **from_ptr, QTestState **to_ptr, MigrateCommon *args) { - g_autofree char *uri = g_strdup_printf("unix:%s/migsocket", tmpfs); QTestState *from, *to; - if (test_migrate_start(&from, &to, uri, &args->start)) { + if (test_migrate_start(&from, &to, "defer", &args->start)) { return -1; } @@ -1262,10 +1261,13 @@ static int migrate_postcopy_prepare(QTestState **from_ptr, migrate_ensure_non_converge(from); migrate_prepare_for_dirty_mem(from); + qtest_qmp_assert_success(to, "{ 'execute': 'migrate-incoming'," + " 'arguments': { 'uri': 'tcp:127.0.0.1:0' }}"); /* Wait for the first serial output from the source */ wait_for_serial("src_serial"); + g_autofree char *uri = migrate_get_socket_address(to, "socket-address"); migrate_qmp(from, uri, "{}"); migrate_wait_for_dirty_mem(from, to); -- 2.40.1