migration: Make multifd_send_set_error() own the error

Make multifd_send_set_error() take ownership of the error always.  Paving
way for making migrate_set_error() to take ownership.

When at it, rename it to multifd_send_error_propagate() to imply the
ownership transition following Error API's naming style.

Reviewed-by: Markus Armbruster <armbru@redhat.com>
Link: https://lore.kernel.org/r/20251201194510.1121221-6-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>

diff --git a/migration/multifd.c b/migration/multifd.c
index 3203dc98e1594ec8483951bcd72428351aef3e34..651ea3d14b3cde26f04e57151b324914e54eb956 100644 (file)
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -414,7 +414,7 @@ bool multifd_send(MultiFDSendData **send_data)
 }
 
 /* Multifd send side hit an error; remember it and prepare to quit */
-static void multifd_send_set_error(Error *err)
+static void multifd_send_error_propagate(Error *err)
 {
     /*
      * We don't want to exit each threads twice.  Depending on where
@@ -429,6 +429,7 @@ static void multifd_send_set_error(Error *err)
     if (err) {
         MigrationState *s = migrate_get_current();
         migrate_set_error(s, err);
+        error_free(err);
         if (s->state == MIGRATION_STATUS_SETUP ||
             s->state == MIGRATION_STATUS_PRE_SWITCHOVER ||
             s->state == MIGRATION_STATUS_DEVICE ||
@@ -777,9 +778,8 @@ out:
     if (ret) {
         assert(local_err);
         trace_multifd_send_error(p->id);
-        multifd_send_set_error(local_err);
+        multifd_send_error_propagate(local_err);
         multifd_send_kick_main(p);
-        error_free(local_err);
     }
 
     rcu_unregister_thread();
@@ -901,14 +901,13 @@ out:
     }
 
     trace_multifd_new_send_channel_async_error(p->id, local_err);
-    multifd_send_set_error(local_err);
+    multifd_send_error_propagate(local_err);
     /*
      * For error cases (TLS or non-TLS), IO channel is always freed here
      * rather than when cleanup multifd: since p->c is not set, multifd
      * cleanup code doesn't even know its existence.
      */
     object_unref(OBJECT(ioc));
-    error_free(local_err);
 }
 
 static bool multifd_new_send_channel_create(gpointer opaque, Error **errp)