[V3,05/10] migration: preserve suspended for bg_migration

Commit Message

Steven Sistare Aug. 14, 2023, 6:54 p.m. UTC

Do not wake a suspended guest during bg_migration.

Signed-off-by: Steve Sistare <[e-mail]>
---
 migration/migration.c | 12 +++++-------
 softmmu/runstate.c    |  1 +
 2 files changed, 6 insertions(+), 7 deletions(-)

Patch

diff --git a/migration/migration.c b/migration/migration.c
index 1a5484a..e6b8024 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -3069,7 +3069,9 @@  static void bg_migration_vm_start_bh(void *opaque)
     qemu_bh_delete(s->vm_start_bh);
     s->vm_start_bh = NULL;
 
-    vm_start();
+    if (!runstate_check(RUN_STATE_SUSPENDED)) {
+        vm_start();
+    }
     s->downtime = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) - s->downtime_start;
 }
 
@@ -3139,16 +3141,12 @@  static void *bg_migration_thread(void *opaque)
 
     qemu_mutex_lock_iothread();
 
-    /*
-     * If VM is currently in suspended state, then, to make a valid runstate
-     * transition in vm_stop_force_state() we need to wakeup it up.
-     */
-    qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER, NULL);
     s->vm_old_state = runstate_get();
 
     global_state_store();
     /* Forcibly stop VM before saving state of vCPUs and devices */
-    if (vm_stop_force_state(RUN_STATE_PAUSED)) {
+    if (!runstate_check(RUN_STATE_SUSPENDED) &&
+        vm_stop_force_state(RUN_STATE_PAUSED)) {
         goto fail;
     }
     /*
diff --git a/softmmu/runstate.c b/softmmu/runstate.c
index 2f70c07..c683dcf 100644
--- a/softmmu/runstate.c
+++ b/softmmu/runstate.c
@@ -163,6 +163,7 @@  static const RunStateTransition runstate_transitions_def[] = {
     { RUN_STATE_SUSPENDED, RUN_STATE_FINISH_MIGRATE },
     { RUN_STATE_SUSPENDED, RUN_STATE_PRELAUNCH },
     { RUN_STATE_SUSPENDED, RUN_STATE_COLO},
+    { RUN_STATE_SUSPENDED, RUN_STATE_PAUSED },
 
     { RUN_STATE_WATCHDOG, RUN_STATE_RUNNING },
     { RUN_STATE_WATCHDOG, RUN_STATE_FINISH_MIGRATE },