set conn deadline

(cherry picked from commit ae00132)

Author: ZHAO

dstore/host.go

@@ -108,82 +108,53 @@ func (host *Host) releaseConn(conn net.Conn) {
 	}
 }
 
-func (host *Host) execute(req *mc.Request) (resp *mc.Response, delta time.Duration, err error) {
-	now := time.Now()
+func (host *Host) executeWithTimeout(req *mc.Request, timeout time.Duration) (resp *mc.Response, err error) {
 	conn, err := host.getConn()
 	if err != nil {
 		return
 	}
+	conn.SetDeadline(time.Now().Add(timeout))
+
+	var reason string
+
+	defer func() {
+		if err != nil {
+			logger.Errorf("error occurred on %s, reason: %s, err: %s", host.Addr, reason, err.Error())
+			if resp != nil {
+				resp.CleanBuffer()
+			}
+			conn.Close()
+		} else {
+			host.releaseConn(conn)
+		}
+	}()
 
 	err = req.Write(conn)
 	if err != nil {
-		logger.Infof("%s write request failed: %v", host.Addr, err)
-		conn.Close()
+		reason = "write request failed"
 		return
 	}
 
 	resp = new(mc.Response)
 	if req.NoReply {
-		host.releaseConn(conn)
 		resp.Status = "STORED"
-		delta = time.Since(now)
 		return
 	}
 
 	reader := bufio.NewReader(conn)
 	if err = resp.Read(reader); err != nil {
-		logger.Infof("%s read response failed: %v", host.Addr, err)
-		conn.Close()
-		return nil, 0, err
+		reason = "read response failed"
+		return nil, err
 	}
 
 	if err = req.Check(resp); err != nil {
-		logger.Infof("%s unexpected response %s %v %v",
-			host.Addr, req, resp, err)
-		conn.Close()
-		return nil, 0, err
+		reason = fmt.Sprintf("unexpected response %v %v",
+			req, resp)
+		return nil, err
 	}
-
-	host.releaseConn(conn)
-	delta = time.Since(now)
 	return
 }
 
-func (host *Host) executeWithTimeout(req *mc.Request, timeout time.Duration) (resp *mc.Response, err error) {
-	var tmpErr error
-	var tmpResp *mc.Response
-	done := make(chan bool)
-	isTimeout := make(chan bool, 1)
-
-	go func() {
-		var delta time.Duration
-		tmpResp, delta, tmpErr = host.execute(req)
-		select {
-		case done <- true:
-		case <-isTimeout:
-			logger.Infof("request %v to host %s return after timeout, use %d ms",
-				req, host.Addr, delta/1e6)
-			if tmpResp != nil {
-				tmpResp.CleanBuffer()
-			}
-		}
-	}()
-
-	timer := time.NewTimer(timeout)
-	defer timer.Stop()
-
-	select {
-	case <-done:
-		resp = tmpResp
-		err = tmpErr
-	case <-timer.C:
-		isTimeout <- true
-		err = fmt.Errorf("request %v timeout", req)
-		logger.Infof("request %v to host %s timeout", req, host.Addr)
-	}
-	return resp, err
-}
-
 func (host *Host) Len() int {
 	return 0
 }
@@ -210,7 +181,7 @@ func (host *Host) Get(key string) (*mc.Item, error) {
 
 func (host *Host) GetMulti(keys []string) (map[string]*mc.Item, error) {
 	req := &mc.Request{Cmd: "get", Keys: keys}
-	resp, _, err := host.execute(req)
+	resp, err := host.executeWithTimeout(req, time.Duration(proxyConf.ReadTimeoutMs)*time.Millisecond)
 	if err != nil {
 		return nil, err
 	}
@@ -221,7 +192,7 @@ func (host *Host) Append(key string, value []byte) (bool, error) {
 	flag := 0
 	item := newItem(flag, value)
 	req := &mc.Request{Cmd: "append", Keys: []string{key}, Item: item}
-	resp, _, err := host.execute(req)
+	resp, err := host.executeWithTimeout(req, time.Duration(proxyConf.ReadTimeoutMs)*time.Millisecond)
 	item.Free()
 	if err == nil {
 		return resp.Status == "STORED", nil
@@ -234,7 +205,7 @@ func (host *Host) Incr(key string, value int) (int, error) {
 	flag := 0
 	item := newItem(flag, []byte(strconv.Itoa(value)))
 	req := &mc.Request{Cmd: "incr", Keys: []string{key}, Item: item}
-	resp, _, err := host.execute(req)
+	resp, err := host.executeWithTimeout(req, time.Duration(proxyConf.ReadTimeoutMs)*time.Millisecond)
 	item.Free()
 	if err != nil {
 		return 0, err
@@ -244,7 +215,7 @@ func (host *Host) Incr(key string, value int) (int, error) {
 
 func (host *Host) Delete(key string) (bool, error) {
 	req := &mc.Request{Cmd: "delete", Keys: []string{key}}
-	resp, _, err := host.execute(req)
+	resp, err := host.executeWithTimeout(req, time.Duration(proxyConf.ReadTimeoutMs)*time.Millisecond)
 	if err == nil {
 		return resp.Status == "DELETED", nil
 	} else {