migration: Switch to COLO process after finishing loadvm

Switch from normal migration loadvm process into COLO checkpoint process if
COLO mode is enabled.

We add three new members to struct MigrationIncomingState,
'have_colo_incoming_thread' and 'colo_incoming_thread' record the COLO
related thread for secondary VM, 'migration_incoming_co' records the
original migration incoming coroutine.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Amit Shah <amit@amitshah.net>

3 files changed, 43 insertions, 0 deletions

diff --git a/migration/colo-comm.c b/migration/colo-comm.c
index a2d5185a8a..bf44f76440 100644
--- a/migration/colo-comm.c
+++ b/migration/colo-comm.c
@@ -49,3 +49,13 @@ void colo_info_init(void)
 {
     vmstate_register(NULL, 0, &colo_state, &colo_info);
 }
+
+bool migration_incoming_enable_colo(void)
+{
+    return colo_info.colo_requested;
+}
+
+void migration_incoming_exit_colo(void)
+{
+    colo_info.colo_requested = false;
+}
diff --git a/migration/colo.c b/migration/colo.c
index f480431972..550cc5f122 100644
--- a/migration/colo.c
+++ b/migration/colo.c
@@ -27,6 +27,13 @@ bool migration_in_colo_state(void)
     return (s->state == MIGRATION_STATUS_COLO);
 }
 
+bool migration_incoming_in_colo_state(void)
+{
+    MigrationIncomingState *mis = migration_incoming_get_current();
+
+    return mis && (mis->state == MIGRATION_STATUS_COLO);
+}
+
 static void colo_process_checkpoint(MigrationState *s)
 {
     qemu_mutex_lock_iothread();
@@ -46,3 +53,17 @@ void migrate_start_colo_process(MigrationState *s)
     colo_process_checkpoint(s);
     qemu_mutex_lock_iothread();
 }
+
+void *colo_process_incoming_thread(void *opaque)
+{
+    MigrationIncomingState *mis = opaque;
+
+    migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
+                      MIGRATION_STATUS_COLO);
+
+    /* TODO: COLO checkpoint restore loop */
+
+    migration_incoming_exit_colo();
+
+    return NULL;
+}
diff --git a/migration/migration.c b/migration/migration.c
index aff3eb460d..d8421b5085 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -407,6 +407,18 @@ static void process_incoming_migration_co(void *opaque)
         /* Else if something went wrong then just fall out of the normal exit */
     }
 
+    /* we get COLO info, and know if we are in COLO mode */
+    if (!ret && migration_incoming_enable_colo()) {
+        mis->migration_incoming_co = qemu_coroutine_self();
+        qemu_thread_create(&mis->colo_incoming_thread, "COLO incoming",
+             colo_process_incoming_thread, mis, QEMU_THREAD_JOINABLE);
+        mis->have_colo_incoming_thread = true;
+        qemu_coroutine_yield();
+
+        /* Wait checkpoint incoming thread exit before free resource */
+        qemu_thread_join(&mis->colo_incoming_thread);
+    }
+
     qemu_fclose(f);
     free_xbzrle_decoded_buf();