remove prefaceTimer

clientconn.go

@@ -1121,8 +1121,6 @@ func (ac *addrConn) createTransport(addr resolver.Address, copts transport.Conne
 		Authority: ac.cc.authority,
 	}
 
-	prefaceTimer := time.NewTimer(time.Until(connectDeadline))
-
 	onGoAway := func(r transport.GoAwayReason) {
 		ac.mu.Lock()
 		ac.adjustParams(r)
@@ -1132,13 +1130,11 @@ func (ac *addrConn) createTransport(addr resolver.Address, copts transport.Conne
 
 	onClose := func() {
 		close(onCloseCalled)
-		prefaceTimer.Stop()
 		reconnect.Fire()
 	}
 
 	onPrefaceReceipt := func() {
 		close(prefaceReceived)
-		prefaceTimer.Stop()
 	}
 
 	connectCtx, cancel := context.WithDeadline(ac.ctx, connectDeadline)
@@ -1164,7 +1160,7 @@ func (ac *addrConn) createTransport(addr resolver.Address, copts transport.Conne
 
 	if ac.dopts.reqHandshake == envconfig.RequireHandshakeOn {
 		select {
-		case <-prefaceTimer.C:
+		case <-time.After(connectDeadline.Sub(time.Now())):
 			// We didn't get the preface in time.
 			newTr.Close()
 			grpclog.Warningf("grpc: addrConn.createTransport failed to connect to %v: didn't receive server preface in time. Reconnecting...", addr)