migration: simplify notifiers

Pass the callback function to add_migration_state_change_notifier so
that migration can initialize the notifier on add and clear it on
delete, which simplifies the call sites.  Shorten the function names
so the extra arg can be added more legibly.  Hide the global notifier
list in a new function migration_call_notifiers, and make it externally
visible so future live update code can call it.

No functional change.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Michael Galaxy <mgalaxy@akamai.com>
Reviewed-by: Michael Galaxy <mgalaxy@akamai.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <1686148954-250144-1-git-send-email-steven.sistare@oracle.com>

diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 29e33ea5ed030382cbae2c198622a30ed64feb95..b85c7946a7d9375b676ed19c3b8e5a593babc7f5 100644 (file)
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -3624,8 +3624,8 @@ static void virtio_net_device_realize(DeviceState *dev, Error **errp)
         n->primary_listener.hide_device = failover_hide_primary_device;
         qatomic_set(&n->failover_primary_hidden, true);
         device_listener_register(&n->primary_listener);
-        n->migration_state.notify = virtio_net_migration_state_notifier;
-        add_migration_state_change_notifier(&n->migration_state);
+        migration_add_notifier(&n->migration_state,
+                               virtio_net_migration_state_notifier);
         n->host_features |= (1ULL << VIRTIO_NET_F_STANDBY);
     }
 
@@ -3788,7 +3788,7 @@ static void virtio_net_device_unrealize(DeviceState *dev)
     if (n->failover) {
         qobject_unref(n->primary_opts);
         device_listener_unregister(&n->primary_listener);
-        remove_migration_state_change_notifier(&n->migration_state);
+        migration_remove_notifier(&n->migration_state);
     } else {
         assert(n->primary_opts == NULL);
     }

diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index 0aaad65c06a1959c2d83f021309959fd2b799afd..28d422b39f9f70e94a2f396b0fb064c5de17dc28 100644 (file)
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -872,8 +872,8 @@ static int vfio_migration_init(VFIODevice *vbasedev)
                      NULL;
     migration->vm_state = qdev_add_vm_change_state_handler_full(
         vbasedev->dev, vfio_vmstate_change, prepare_cb, vbasedev);
-    migration->migration_state.notify = vfio_migration_state_notifier;
-    add_migration_state_change_notifier(&migration->migration_state);
+    migration_add_notifier(&migration->migration_state,
+                           vfio_migration_state_notifier);
 
     return 0;
 }
@@ -882,7 +882,7 @@ static void vfio_migration_deinit(VFIODevice *vbasedev)
 {
     VFIOMigration *migration = vbasedev->migration;
 
-    remove_migration_state_change_notifier(&migration->migration_state);
+    migration_remove_notifier(&migration->migration_state);
     qemu_del_vm_change_state_handler(migration->vm_state);
     unregister_savevm(VMSTATE_IF(vbasedev->dev), "vfio", vbasedev);
     vfio_migration_free(vbasedev);

diff --git a/include/migration/misc.h b/include/migration/misc.h
index 7dcc0b5c2cc99e45ccdc699826540efd7478e969..673ac490fb36bcf4d3e3f1446703c817dd982c5a 100644 (file)
--- a/include/migration/misc.h
+++ b/include/migration/misc.h
@@ -60,8 +60,10 @@ void migration_object_init(void);
 void migration_shutdown(void);
 bool migration_is_idle(void);
 bool migration_is_active(MigrationState *);
-void add_migration_state_change_notifier(Notifier *notify);
-void remove_migration_state_change_notifier(Notifier *notify);
+void migration_add_notifier(Notifier *notify,
+                            void (*func)(Notifier *notifier, void *data));
+void migration_remove_notifier(Notifier *notify);
+void migration_call_notifiers(MigrationState *s);
 bool migration_in_setup(MigrationState *);
 bool migration_has_finished(MigrationState *);
 bool migration_has_failed(MigrationState *);

diff --git a/migration/migration.c b/migration/migration.c
index 818b02b70784a781ca64d0bbe65a1004f376f2b3..67547eb6a1d2c777d87d7eb402ea1ddc40b334c7 100644 (file)
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1207,7 +1207,7 @@ static void migrate_fd_cleanup(MigrationState *s)
         /* It is used on info migrate.  We can't free it */
         error_report_err(error_copy(s->error));
     }
-    notifier_list_notify(&migration_state_notifiers, s);
+    migration_call_notifiers(s);
     block_cleanup_parameters();
     yank_unregister_instance(MIGRATION_YANK_INSTANCE);
 }
@@ -1311,14 +1311,24 @@ static void migrate_fd_cancel(MigrationState *s)
     }
 }
 
-void add_migration_state_change_notifier(Notifier *notify)
+void migration_add_notifier(Notifier *notify,
+                            void (*func)(Notifier *notifier, void *data))
 {
+    notify->notify = func;
     notifier_list_add(&migration_state_notifiers, notify);
 }
 
-void remove_migration_state_change_notifier(Notifier *notify)
+void migration_remove_notifier(Notifier *notify)
+{
+    if (notify->notify) {
+        notifier_remove(notify);
+        notify->notify = NULL;
+    }
+}
+
+void migration_call_notifiers(MigrationState *s)
 {
-    notifier_remove(notify);
+    notifier_list_notify(&migration_state_notifiers, s);
 }
 
 bool migration_in_setup(MigrationState *s)
@@ -2233,7 +2243,7 @@ static int postcopy_start(MigrationState *ms, Error **errp)
      * spice needs to trigger a transition now
      */
     ms->postcopy_after_devices = true;
-    notifier_list_notify(&migration_state_notifiers, ms);
+    migration_call_notifiers(ms);
 
     ms->downtime =  qemu_clock_get_ms(QEMU_CLOCK_REALTIME) - time_at_stop;
 
@@ -3313,7 +3323,7 @@ void migrate_fd_connect(MigrationState *s, Error *error_in)
         rate_limit = migrate_max_bandwidth();
 
         /* Notify before starting migration thread */
-        notifier_list_notify(&migration_state_notifiers, s);
+        migration_call_notifiers(s);
     }
 
     migration_rate_set(rate_limit);

diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
index 939c984d5b91fb441708f89169223563b8279e7e..0f2e6fc58ee0284012d23a15df76c913f3819903 100644 (file)
--- a/net/vhost-vdpa.c
+++ b/net/vhost-vdpa.c
@@ -339,7 +339,8 @@ static void vhost_vdpa_net_data_start_first(VhostVDPAState *s)
 {
     struct vhost_vdpa *v = &s->vhost_vdpa;
 
-    add_migration_state_change_notifier(&s->migration_state);
+    migration_add_notifier(&s->migration_state,
+                           vdpa_net_migration_state_notifier);
     if (v->shadow_vqs_enabled) {
         v->iova_tree = vhost_iova_tree_new(v->iova_range.first,
                                            v->iova_range.last);
@@ -399,7 +400,7 @@ static void vhost_vdpa_net_client_stop(NetClientState *nc)
     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
 
     if (s->vhost_vdpa.index == 0) {
-        remove_migration_state_change_notifier(&s->migration_state);
+        migration_remove_notifier(&s->migration_state);
     }
 
     dev = s->vhost_vdpa.dev;
@@ -1456,7 +1457,7 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer,
     s->vhost_vdpa.device_fd = vdpa_device_fd;
     s->vhost_vdpa.index = queue_pair_index;
     s->always_svq = svq;
-    s->migration_state.notify = vdpa_net_migration_state_notifier;
+    s->migration_state.notify = NULL;
     s->vhost_vdpa.shadow_vqs_enabled = svq;
     s->vhost_vdpa.iova_range = iova_range;
     s->vhost_vdpa.shadow_data = svq;

diff --git a/ui/spice-core.c b/ui/spice-core.c
index 52a59386d7423add30d8ad018a2ff875c3d0c449..db21db2c9428225defe66f8904e4fb7dd90bac33 100644 (file)
--- a/ui/spice-core.c
+++ b/ui/spice-core.c
@@ -821,8 +821,7 @@ static void qemu_spice_init(void)
     };
     using_spice = 1;
 
-    migration_state.notify = migration_state_notifier;
-    add_migration_state_change_notifier(&migration_state);
+    migration_add_notifier(&migration_state, migration_state_notifier);
     spice_migrate.base.sif = &migrate_interface.base;
     qemu_spice.add_interface(&spice_migrate.base);