remove transportSeq

call.go

@@ -142,7 +142,6 @@ func Invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 		Delay: false,
 	}
 	var (
-		ts      int   // track the transport sequence number
 		lastErr error // record the error that happened
 	)
 	for {
@@ -155,7 +154,7 @@ func Invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 		if lastErr != nil && c.failFast {
 			return toRPCErr(lastErr)
 		}
-		t, ts, err = cc.wait(ctx, ts)
+		t, err = cc.wait(ctx)
 		if err != nil {
 			if lastErr != nil {
 				// This was a retry; return the error from the last attempt.

clientconn.go

@@ -403,19 +403,17 @@ func (cc *ClientConn) transportMonitor() {
 }
 
 // When wait returns, either the new transport is up or ClientConn is
-// closing. Used to avoid working on a dying transport. It updates and
-// returns the transport and its version when there is no error.
-func (cc *ClientConn) wait(ctx context.Context, ts int) (transport.ClientTransport, int, error) {
+// closing.
+func (cc *ClientConn) wait(ctx context.Context) (transport.ClientTransport, error) {
 	for {
 		cc.mu.Lock()
 		switch {
 		case cc.state == Shutdown:
 			cc.mu.Unlock()
-			return nil, 0, ErrClientConnClosing
-		case ts < cc.transportSeq:
-			// Worked on a dying transport. Try the new one immediately.
-			defer cc.mu.Unlock()
-			return cc.transport, cc.transportSeq, nil
+			return nil, ErrClientConnClosing
+		case cc.state == Ready:
+			cc.mu.Unlock()
+			return cc.transport, nil
 		default:
 			ready := cc.ready
 			if ready == nil {
@@ -425,7 +423,7 @@ func (cc *ClientConn) wait(ctx context.Context, ts int) (transport.ClientTranspo
 			cc.mu.Unlock()
 			select {
 			case <-ctx.Done():
-				return nil, 0, transport.ContextErr(ctx.Err())
+				return nil, transport.ContextErr(ctx.Err())
 			// Wait until the new transport is ready or failed.
 			case <-ready:
 			}

stream.go

@@ -114,7 +114,7 @@ func NewClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 		}
 		cs.traceInfo.tr.LazyLog(&cs.traceInfo.firstLine, false)
 	}
-	t, _, err := cc.wait(ctx, 0)
+	t, err := cc.wait(ctx)
 	if err != nil {
 		return nil, toRPCErr(err)
 	}