daemon: containerStop: fix ordering of "stop" and "die" events

Commit 8e6cd44ce4 added synchronisation to
wait for the container's status to be updated in memory. However, since
952902efbc, a defer was used to produce
the container's "stop" event.

As a result of the sychronisation that was added, the "die" event would
now be produced before the "stop" event.

This patch moves the locking inside the defer to restore the previous
behavior.

Unfortunately the order of events is still not guaranteed, because events
are emited from multiple goroutines that don't have synchronisation between
them; this is something to look at for follow ups. This patch keeps the status
quo and should preserve the old behavior, which was "more" correct in most
cases.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

daemon/stop.go

@@ -74,6 +74,9 @@ func (daemon *Daemon) containerStop(ctx context.Context, ctr *container.Containe
 	defer func() {
 		if retErr == nil {
 			daemon.LogContainerEvent(ctr, events.ActionStop)
+			// Ensure container status changes are committed by handler of container exit before returning control to the caller
+			ctr.Lock()
+			defer ctr.Unlock()
 		}
 	}()
 
@@ -93,9 +96,6 @@ func (daemon *Daemon) containerStop(ctx context.Context, ctr *container.Containe
 	defer cancel()
 
 	if status := <-ctr.Wait(subCtx, containertypes.WaitConditionNotRunning); status.Err() == nil {
-		// Ensure container status changes are committed by handler of container exit before returning control to the caller
-		ctr.Lock()
-		defer ctr.Unlock()
 		// container did exit, so ignore any previous errors and return
 		return nil
 	}
@@ -125,9 +125,5 @@ func (daemon *Daemon) containerStop(ctx context.Context, ctr *container.Containe
 		// container did exit, so ignore previous errors and continue
 	}
 
-	// Ensure container status changes are committed by handler of container exit before returning control to the caller
-	ctr.Lock()
-	defer ctr.Unlock()
-
 	return nil
 }