[pve-devel] [PATCH qemu 3/6] savevm-async: improve runstate preservation

[Fiona Ebner]

Determine if VM needs to be started after finishing right before
actually stopping the VM instead of at the beginning.

In qmp_savevm_start(), the only path stopping the VM returns right
aftwards, so there is no need for the vm_start() handling after
errors. The next commit will inline the remaining error handling and
avoid the confusing naming of the 'restart' goto label.

Signed-off-by: Fiona Ebner <f.ebner at proxmox.com>
---
 migration/savevm-async.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/migration/savevm-async.c b/migration/savevm-async.c
index 1e34c31e8b..72d8ed2739 100644
--- a/migration/savevm-async.c
+++ b/migration/savevm-async.c
@@ -178,6 +178,7 @@ static void process_savevm_finalize(void *opaque)
      */
     blk_set_aio_context(snap_state.target, qemu_get_aio_context(), NULL);
 
+    snap_state.vm_needs_start = runstate_is_running();
     ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
     if (ret < 0) {
         save_snapshot_error("vm_stop_force_state error %d", ret);
@@ -352,7 +353,6 @@ void qmp_savevm_start(const char *statefile, Error **errp)
     }
 
     /* initialize snapshot info */
-    snap_state.vm_needs_start = runstate_is_running();
     snap_state.bs_pos = 0;
     snap_state.total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
     snap_state.blocker = NULL;
@@ -364,6 +364,7 @@ void qmp_savevm_start(const char *statefile, Error **errp)
     }
 
     if (!statefile) {
+        snap_state.vm_needs_start = runstate_is_running();
         vm_stop(RUN_STATE_SAVE_VM);
         snap_state.state = SAVE_STATE_COMPLETED;
         return;
@@ -439,11 +440,6 @@ void qmp_savevm_start(const char *statefile, Error **errp)
 restart:
 
     save_snapshot_error("setup failed");
-
-    if (snap_state.vm_needs_start) {
-        vm_start();
-        snap_state.vm_needs_start = false;
-    }
 }
 
 static void coroutine_fn wait_for_close_co(void *opaque)
-- 
2.39.5