[PULL 07/14] tests: wait max 120 seconds for migration test status changes

[Thomas Huth <thuth@redhat.com>]

From: Daniel P. Berrangé <berrange@redhat.com>

Currently the wait_for_migration_fail and wait_for_migration_complete
functions will spin in an infinite loop checking query-migrate status
to detect a specific change/goal. This is fine when everything goes
to plan, but when the unusual happens, these will hang the test suite
forever.

Any normally executing migration test case normally takes < 1 second
for a state change, with exception of the autoconverge test which
takes about 5 seconds. Taking into account possibility of people
running tests inside TCG, allowing a factor of x20 slowdown gives
a reasonable worst case of 120 seconds. Anything taking longer than
this is a strong sign that the test has hung, or the test should be
rewritten to be faster.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20220628105434.295905-2-berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 tests/qtest/migration-helpers.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/tests/qtest/migration-helpers.c b/tests/qtest/migration-helpers.c
index a6aa59e4e6..e81e831c85 100644
--- a/tests/qtest/migration-helpers.c
+++ b/tests/qtest/migration-helpers.c
@@ -15,6 +15,14 @@
 
 #include "migration-helpers.h"
 
+/*
+ * Number of seconds we wait when looking for migration
+ * status changes, to avoid test suite hanging forever
+ * when things go wrong. Needs to be higher enough to
+ * avoid false positives on loaded hosts.
+ */
+#define MIGRATION_STATUS_WAIT_TIMEOUT 120
+
 bool got_stop;
 
 static void check_stop_event(QTestState *who)
@@ -166,8 +174,11 @@ static bool check_migration_status(QTestState *who, const char *goal,
 void wait_for_migration_status(QTestState *who,
                                const char *goal, const char **ungoals)
 {
+    g_test_timer_start();
     while (!check_migration_status(who, goal, ungoals)) {
         usleep(1000);
+
+        g_assert(g_test_timer_elapsed() < MIGRATION_STATUS_WAIT_TIMEOUT);
     }
 }
 
@@ -178,6 +189,7 @@ void wait_for_migration_complete(QTestState *who)
 
 void wait_for_migration_fail(QTestState *from, bool allow_active)
 {
+    g_test_timer_start();
     QDict *rsp_return;
     char *status;
     bool failed;
@@ -193,6 +205,8 @@ void wait_for_migration_fail(QTestState *from, bool allow_active)
         g_assert(result);
         failed = !strcmp(status, "failed");
         g_free(status);
+
+        g_assert(g_test_timer_elapsed() < MIGRATION_STATUS_WAIT_TIMEOUT);
     } while (!failed);
 
     /* Is the machine currently running? */
-- 
2.31.1