Fix race condition in sending started signal from monitor

Signed-off-by: Alexandr Morozov <lk4d4math@gmail.com>
moby · Aug 14, 2014 · 1480168 · 1480168
1 parent 1711270
commit 1480168
Showing 1 changed file with 5 additions and 3 deletions.
diff --git a/daemon/monitor.go b/daemon/monitor.go
@@ -244,10 +244,12 @@ func (m *containerMonitor) callback(command *execdriver.Command) {
 
 	m.container.State.SetRunning(command.Pid())
 
-	if m.startSignal != nil {
-		// signal that the process has started
+	// signal that the process has started
+	// close channel only if not closed
+	select {
+	case <-m.startSignal:
+	default:
 		close(m.startSignal)
-		m.startSignal = nil
 	}
 
 	if err := m.container.ToDisk(); err != nil {