X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=core%2Fconnection.go;h=f3ff964e28b55f26efc9f37452be169ce479ce48;hb=bcf3fbd21aa22d1546bc85ffb887ae5ba557808e;hp=c77358f76cb0c9f3543461550cdc8808c07dc7a3;hpb=a3bb834db727a3ac9a1ffcfeae9265e5dead851f;p=govpp.git diff --git a/core/connection.go b/core/connection.go index c77358f..f3ff964 100644 --- a/core/connection.go +++ b/core/connection.go @@ -17,6 +17,7 @@ package core import ( "errors" "fmt" + "path" "reflect" "sync" "sync/atomic" @@ -30,40 +31,22 @@ import ( ) const ( - requestChannelBufSize = 100 // default size of the request channel buffer - replyChannelBufSize = 100 // default size of the reply channel buffer - notificationChannelBufSize = 100 // default size of the notification channel buffer - - defaultReplyTimeout = time.Second * 1 // default timeout for replies from VPP, can be changed with SetReplyTimeout + DefaultReconnectInterval = time.Second / 2 // default interval between reconnect attempts + DefaultMaxReconnectAttempts = 3 // default maximum number of reconnect attempts ) var ( - healthCheckInterval = time.Second * 1 // default health check interval - healthCheckReplyTimeout = time.Millisecond * 100 // timeout for reply to a health check - healthCheckThreshold = 1 // number of failed health checks until the error is reported + RequestChanBufSize = 100 // default size of the request channel buffer + ReplyChanBufSize = 100 // default size of the reply channel buffer + NotificationChanBufSize = 100 // default size of the notification channel buffer ) -// SetHealthCheckProbeInterval sets health check probe interval. -// Beware: Function is not thread-safe. It is recommended to setup this parameter -// before connecting to vpp. -func SetHealthCheckProbeInterval(interval time.Duration) { - healthCheckInterval = interval -} - -// SetHealthCheckReplyTimeout sets timeout for reply to a health check probe. -// If reply arrives after the timeout, check is considered as failed. -// Beware: Function is not thread-safe. It is recommended to setup this parameter -// before connecting to vpp. -func SetHealthCheckReplyTimeout(timeout time.Duration) { - healthCheckReplyTimeout = timeout -} - -// SetHealthCheckThreshold sets the number of failed healthProbe checks until the error is reported. -// Beware: Function is not thread-safe. It is recommended to setup this parameter -// before connecting to vpp. -func SetHealthCheckThreshold(threshold int) { - healthCheckThreshold = threshold -} +var ( + HealthCheckProbeInterval = time.Second // default health check probe interval + HealthCheckReplyTimeout = time.Millisecond * 250 // timeout for reply to a health check probe + HealthCheckThreshold = 2 // number of failed health checks until the error is reported + DefaultReplyTimeout = time.Second // default timeout for replies from VPP +) // ConnectionState represents the current state of the connection to VPP. type ConnectionState int @@ -72,10 +55,32 @@ const ( // Connected represents state in which the connection has been successfully established. Connected ConnectionState = iota - // Disconnected represents state in which the connection has been dropped. + // NotResponding represents a state where the VPP socket accepts messages but replies are received with delay, + // or not at all. GoVPP treats this state internally the same as disconnected. + NotResponding + + // Disconnected represents state in which the VPP socket is closed and the connection is considered dropped. Disconnected + + // Failed represents state in which the reconnecting failed after exceeding maximum number of attempts. + Failed ) +func (s ConnectionState) String() string { + switch s { + case Connected: + return "Connected" + case NotResponding: + return "NotResponding" + case Disconnected: + return "Disconnected" + case Failed: + return "Failed" + default: + return fmt.Sprintf("UnknownState(%d)", s) + } +} + // ConnectionEvent is a notification about change in the VPP connection state. type ConnectionEvent struct { // Timestamp holds the time when the event has been created. @@ -88,46 +93,72 @@ type ConnectionEvent struct { Error error } -var ( - connLock sync.RWMutex // lock for the global connection - conn *Connection // global handle to the Connection (used in the message receive callback) -) - // Connection represents a shared memory connection to VPP via vppAdapter. type Connection struct { - vpp adapter.VppAdapter // VPP adapter - connected uint32 // non-zero if the adapter is connected to VPP + vppClient adapter.VppAPI // VPP binary API client + + maxAttempts int // interval for reconnect attempts + recInterval time.Duration // maximum number of reconnect attempts - codec *codec.MsgCodec // message codec - msgIDs map[string]uint16 // map of message IDs indexed by message name + CRC - msgMap map[uint16]api.Message // map of messages indexed by message ID + vppConnected uint32 // non-zero if the adapter is connected to VPP + + connChan chan ConnectionEvent // connection status events are sent to this channel + + codec MessageCodec // message codec + msgIDs map[string]uint16 // map of message IDs indexed by message name + CRC + msgMapByPath map[string]map[uint16]api.Message // map of messages indexed by message ID which are indexed by path maxChannelID uint32 // maximum used channel ID (the real limit is 2^15, 32-bit is used for atomic operations) channelsLock sync.RWMutex // lock for the channels map - channels map[uint16]*channel // map of all API channels indexed by the channel ID + channels map[uint16]*Channel // map of all API channels indexed by the channel ID - notifSubscriptionsLock sync.RWMutex // lock for the subscriptions map - notifSubscriptions map[uint16][]*api.NotifSubscription // map od all notification subscriptions indexed by message ID + subscriptionsLock sync.RWMutex // lock for the subscriptions map + subscriptions map[uint16][]*subscriptionCtx // map od all notification subscriptions indexed by message ID pingReqID uint16 // ID if the ControlPing message pingReplyID uint16 // ID of the ControlPingReply message lastReplyLock sync.Mutex // lock for the last reply lastReply time.Time // time of the last received reply from VPP + + msgControlPing api.Message + msgControlPingReply api.Message } -// Connect connects to VPP using specified VPP adapter and returns the connection handle. -// This call blocks until VPP is connected, or an error occurs. Only one connection attempt will be performed. -func Connect(vppAdapter adapter.VppAdapter) (*Connection, error) { - // create new connection handle - c, err := newConnection(vppAdapter) - if err != nil { - return nil, err +func newConnection(binapi adapter.VppAPI, attempts int, interval time.Duration) *Connection { + if attempts == 0 { + attempts = DefaultMaxReconnectAttempts + } + if interval == 0 { + interval = DefaultReconnectInterval + } + + c := &Connection{ + vppClient: binapi, + maxAttempts: attempts, + recInterval: interval, + connChan: make(chan ConnectionEvent, NotificationChanBufSize), + codec: codec.DefaultCodec, + msgIDs: make(map[string]uint16), + msgMapByPath: make(map[string]map[uint16]api.Message), + channels: make(map[uint16]*Channel), + subscriptions: make(map[uint16][]*subscriptionCtx), + msgControlPing: msgControlPing, + msgControlPingReply: msgControlPingReply, } + binapi.SetMsgCallback(c.msgCallback) + return c +} + +// Connect connects to VPP API using specified adapter and returns a connection handle. +// This call blocks until it is either connected, or an error occurs. +// Only one connection attempt will be performed. +func Connect(binapi adapter.VppAPI) (*Connection, error) { + // create new connection handle + c := newConnection(binapi, DefaultMaxReconnectAttempts, DefaultReconnectInterval) // blocking attempt to connect to VPP - err = c.connectVPP() - if err != nil { + if err := c.connectVPP(); err != nil { return nil, err } @@ -138,55 +169,14 @@ func Connect(vppAdapter adapter.VppAdapter) (*Connection, error) { // and ConnectionState channel. This call does not block until connection is established, it // returns immediately. The caller is supposed to watch the returned ConnectionState channel for // Connected/Disconnected events. In case of disconnect, the library will asynchronously try to reconnect. -func AsyncConnect(vppAdapter adapter.VppAdapter) (*Connection, chan ConnectionEvent, error) { +func AsyncConnect(binapi adapter.VppAPI, attempts int, interval time.Duration) (*Connection, chan ConnectionEvent, error) { // create new connection handle - c, err := newConnection(vppAdapter) - if err != nil { - return nil, nil, err - } + c := newConnection(binapi, attempts, interval) // asynchronously attempt to connect to VPP - connChan := make(chan ConnectionEvent, notificationChannelBufSize) - go c.connectLoop(connChan) + go c.connectLoop() - return c, connChan, nil -} - -// Disconnect disconnects from VPP and releases all connection-related resources. -func (c *Connection) Disconnect() { - if c == nil { - return - } - - connLock.Lock() - defer connLock.Unlock() - - if c.vpp != nil { - c.disconnectVPP() - } - conn = nil -} - -// newConnection returns new connection handle. -func newConnection(vppAdapter adapter.VppAdapter) (*Connection, error) { - connLock.Lock() - defer connLock.Unlock() - - if conn != nil { - return nil, errors.New("only one connection per process is supported") - } - - conn = &Connection{ - vpp: vppAdapter, - codec: &codec.MsgCodec{}, - channels: make(map[uint16]*channel), - msgIDs: make(map[string]uint16), - msgMap: make(map[uint16]api.Message), - notifSubscriptions: make(map[uint16][]*api.NotifSubscription), - } - conn.vpp.SetMsgCallback(conn.msgCallback) - - return conn, nil + return c, c.connChan, nil } // connectVPP performs blocking attempt to connect to VPP. @@ -194,138 +184,119 @@ func (c *Connection) connectVPP() error { log.Debug("Connecting to VPP..") // blocking connect - if err := c.vpp.Connect(); err != nil { + if err := c.vppClient.Connect(); err != nil { return err } - - log.Debugf("Connected to VPP.") + log.Debugf("Connected to VPP") if err := c.retrieveMessageIDs(); err != nil { - c.vpp.Disconnect() + if err := c.vppClient.Disconnect(); err != nil { + log.Debugf("disconnecting vpp client failed: %v", err) + } return fmt.Errorf("VPP is incompatible: %v", err) } // store connected state - atomic.StoreUint32(&c.connected, 1) + atomic.StoreUint32(&c.vppConnected, 1) return nil } -func getMsgNameWithCrc(x api.Message) string { - return x.GetMessageName() + "_" + x.GetCrcString() -} - -// retrieveMessageIDs retrieves IDs for all registered messages and stores them in map -func (c *Connection) retrieveMessageIDs() (err error) { - t := time.Now() - - var addMsg = func(msgID uint16, msg api.Message) { - c.msgIDs[getMsgNameWithCrc(msg)] = msgID - c.msgMap[msgID] = msg +// Disconnect disconnects from VPP API and releases all connection-related resources. +func (c *Connection) Disconnect() { + if c == nil { + return } - - msgs := api.GetAllMessages() - - for name, msg := range msgs { - msgID, err := c.vpp.GetMsgID(msg.GetMessageName(), msg.GetCrcString()) - if err != nil { - return err - } - - addMsg(msgID, msg) - - if msg.GetMessageName() == msgControlPing.GetMessageName() { - c.pingReqID = msgID - msgControlPing = reflect.New(reflect.TypeOf(msg).Elem()).Interface().(api.Message) - } else if msg.GetMessageName() == msgControlPingReply.GetMessageName() { - c.pingReplyID = msgID - msgControlPingReply = reflect.New(reflect.TypeOf(msg).Elem()).Interface().(api.Message) - } - - if debugMsgIDs { - log.Debugf("message %q (%s) has ID: %d", name, getMsgNameWithCrc(msg), msgID) - } + if c.vppClient != nil { + c.disconnectVPP() } +} - log.Debugf("retrieving %d message IDs took %s", len(msgs), time.Since(t)) +// disconnectVPP disconnects from VPP in case it is connected. +func (c *Connection) disconnectVPP() { + if atomic.CompareAndSwapUint32(&c.vppConnected, 1, 0) { + log.Debug("Disconnecting from VPP..") - // fallback for control ping when vpe package is not imported - if c.pingReqID == 0 { - c.pingReqID, err = c.vpp.GetMsgID(msgControlPing.GetMessageName(), msgControlPing.GetCrcString()) - if err != nil { - return err - } - addMsg(c.pingReqID, msgControlPing) - } - if c.pingReplyID == 0 { - c.pingReplyID, err = c.vpp.GetMsgID(msgControlPingReply.GetMessageName(), msgControlPingReply.GetCrcString()) - if err != nil { - return err + if err := c.vppClient.Disconnect(); err != nil { + log.Debugf("Disconnect from VPP failed: %v", err) } - addMsg(c.pingReplyID, msgControlPingReply) + log.Debug("Disconnected from VPP") } - - return nil } -// GetMessageID returns message identifier of given API message. -func (c *Connection) GetMessageID(msg api.Message) (uint16, error) { - if c == nil { - return 0, errors.New("nil connection passed in") - } - - if msgID, ok := c.msgIDs[getMsgNameWithCrc(msg)]; ok { - return msgID, nil - } +func (c *Connection) NewAPIChannel() (api.Channel, error) { + return c.newAPIChannel(RequestChanBufSize, ReplyChanBufSize) +} - return 0, fmt.Errorf("unknown message: %s (%s)", msg.GetMessageName(), msg.GetCrcString()) +func (c *Connection) NewAPIChannelBuffered(reqChanBufSize, replyChanBufSize int) (api.Channel, error) { + return c.newAPIChannel(reqChanBufSize, replyChanBufSize) } -// LookupByID looks up message name and crc by ID. -func (c *Connection) LookupByID(msgID uint16) (api.Message, error) { +// NewAPIChannelBuffered returns a new API channel for communication with VPP via govpp core. +// It allows to specify custom buffer sizes for the request and reply Go channels. +func (c *Connection) newAPIChannel(reqChanBufSize, replyChanBufSize int) (*Channel, error) { if c == nil { return nil, errors.New("nil connection passed in") } - if msg, ok := c.msgMap[msgID]; ok { - return msg, nil - } + // create new channel + chID := uint16(atomic.AddUint32(&c.maxChannelID, 1) & 0x7fff) + channel := newChannel(chID, c, c.codec, c, reqChanBufSize, replyChanBufSize) - return nil, fmt.Errorf("unknown message ID: %d", msgID) + // store API channel within the client + c.channelsLock.Lock() + c.channels[chID] = channel + c.channelsLock.Unlock() + + // start watching on the request channel + go c.watchRequests(channel) + + return channel, nil } -// disconnectVPP disconnects from VPP in case it is connected. -func (c *Connection) disconnectVPP() { - if atomic.CompareAndSwapUint32(&c.connected, 1, 0) { - c.vpp.Disconnect() - } +// releaseAPIChannel releases API channel that needs to be closed. +func (c *Connection) releaseAPIChannel(ch *Channel) { + log.WithFields(logger.Fields{ + "channel": ch.id, + }).Debug("API channel released") + + // delete the channel from channels map + c.channelsLock.Lock() + delete(c.channels, ch.id) + c.channelsLock.Unlock() } // connectLoop attempts to connect to VPP until it succeeds. // Then it continues with healthCheckLoop. -func (c *Connection) connectLoop(connChan chan ConnectionEvent) { +func (c *Connection) connectLoop() { + var reconnectAttempts int + // loop until connected for { - if err := c.vpp.WaitReady(); err != nil { - log.Warnf("wait ready failed: %v", err) + if err := c.vppClient.WaitReady(); err != nil { + log.Debugf("wait ready failed: %v", err) } if err := c.connectVPP(); err == nil { // signal connected event - connChan <- ConnectionEvent{Timestamp: time.Now(), State: Connected} + c.sendConnEvent(ConnectionEvent{Timestamp: time.Now(), State: Connected}) break + } else if reconnectAttempts < c.maxAttempts { + reconnectAttempts++ + log.Warnf("connecting failed (attempt %d/%d): %v", reconnectAttempts, c.maxAttempts, err) + time.Sleep(c.recInterval) } else { - log.Errorf("connecting to VPP failed: %v", err) - time.Sleep(time.Second) + c.sendConnEvent(ConnectionEvent{Timestamp: time.Now(), State: Failed, Error: err}) + return } } // we are now connected, continue with health check loop - c.healthCheckLoop(connChan) + c.healthCheckLoop() } // healthCheckLoop checks whether connection to VPP is alive. In case of disconnect, // it continues with connectLoop and tries to reconnect. -func (c *Connection) healthCheckLoop(connChan chan ConnectionEvent) { +func (c *Connection) healthCheckLoop() { // create a separate API channel for health check probes ch, err := c.newAPIChannel(1, 1) if err != nil { @@ -341,9 +312,9 @@ func (c *Connection) healthCheckLoop(connChan chan ConnectionEvent) { // send health check probes until an error or timeout occurs for { // sleep until next health check probe period - time.Sleep(healthCheckInterval) + time.Sleep(HealthCheckProbeInterval) - if atomic.LoadUint32(&c.connected) == 0 { + if atomic.LoadUint32(&c.vppConnected) == 0 { // Disconnect has been called in the meantime, return the healthcheck - reconnect loop log.Debug("Disconnected on request, exiting health check loop.") return @@ -357,7 +328,7 @@ func (c *Connection) healthCheckLoop(connChan chan ConnectionEvent) { } // send the control ping request - ch.reqChan <- &vppRequest{msg: msgControlPing} + ch.reqChan <- &vppRequest{msg: c.msgControlPing} for { // expect response within timeout period @@ -365,7 +336,7 @@ func (c *Connection) healthCheckLoop(connChan chan ConnectionEvent) { case vppReply := <-ch.replyChan: err = vppReply.err - case <-time.After(healthCheckReplyTimeout): + case <-time.After(HealthCheckReplyTimeout): err = ErrProbeTimeout // check if time since last reply from any other @@ -374,7 +345,7 @@ func (c *Connection) healthCheckLoop(connChan chan ConnectionEvent) { sinceLastReply = time.Since(c.lastReply) c.lastReplyLock.Unlock() - if sinceLastReply < healthCheckReplyTimeout { + if sinceLastReply < HealthCheckReplyTimeout { log.Warnf("VPP health check probe timing out, but some request on other channel was received %v ago, continue waiting!", sinceLastReply) continue } @@ -384,17 +355,17 @@ func (c *Connection) healthCheckLoop(connChan chan ConnectionEvent) { if err == ErrProbeTimeout { failedChecks++ - log.Warnf("VPP health check probe timed out after %v (%d. timeout)", healthCheckReplyTimeout, failedChecks) - if failedChecks > healthCheckThreshold { - // in case of exceeded failed check treshold, assume VPP disconnected - log.Errorf("VPP health check exceeded treshold for timeouts (>%d), assuming disconnect", healthCheckThreshold) - connChan <- ConnectionEvent{Timestamp: time.Now(), State: Disconnected} + log.Warnf("VPP health check probe timed out after %v (%d. timeout)", HealthCheckReplyTimeout, failedChecks) + if failedChecks > HealthCheckThreshold { + // in case of exceeded failed check threshold, assume VPP unresponsive + log.Errorf("VPP does not responding, the health check exceeded threshold for timeouts (>%d)", HealthCheckThreshold) + c.sendConnEvent(ConnectionEvent{Timestamp: time.Now(), State: NotResponding}) break } } else if err != nil { // in case of error, assume VPP disconnected log.Errorf("VPP health check probe failed: %v", err) - connChan <- ConnectionEvent{Timestamp: time.Now(), State: Disconnected, Error: err} + c.sendConnEvent(ConnectionEvent{Timestamp: time.Now(), State: Disconnected, Error: err}) break } else if failedChecks > 0 { // in case of success after failed checks, clear failed check counter @@ -408,55 +379,104 @@ func (c *Connection) healthCheckLoop(connChan chan ConnectionEvent) { c.disconnectVPP() // we are now disconnected, start connect loop - c.connectLoop(connChan) + c.connectLoop() } -func (c *Connection) NewAPIChannel() (api.Channel, error) { - return c.newAPIChannel(requestChannelBufSize, replyChannelBufSize) +func getMsgNameWithCrc(x api.Message) string { + return getMsgID(x.GetMessageName(), x.GetCrcString()) } -func (c *Connection) NewAPIChannelBuffered(reqChanBufSize, replyChanBufSize int) (api.Channel, error) { - return c.newAPIChannel(reqChanBufSize, replyChanBufSize) +func getMsgID(name, crc string) string { + return name + "_" + crc } -// NewAPIChannelBuffered returns a new API channel for communication with VPP via govpp core. -// It allows to specify custom buffer sizes for the request and reply Go channels. -func (c *Connection) newAPIChannel(reqChanBufSize, replyChanBufSize int) (*channel, error) { +func getMsgFactory(msg api.Message) func() api.Message { + return func() api.Message { + return reflect.New(reflect.TypeOf(msg).Elem()).Interface().(api.Message) + } +} + +// GetMessageID returns message identifier of given API message. +func (c *Connection) GetMessageID(msg api.Message) (uint16, error) { if c == nil { - return nil, errors.New("nil connection passed in") + return 0, errors.New("nil connection passed in") + } + pkgPath := c.GetMessagePath(msg) + msgID, err := c.vppClient.GetMsgID(msg.GetMessageName(), msg.GetCrcString()) + if err != nil { + return 0, err + } + if pathMsgs, pathOk := c.msgMapByPath[pkgPath]; !pathOk { + c.msgMapByPath[pkgPath] = make(map[uint16]api.Message) + c.msgMapByPath[pkgPath][msgID] = msg + } else if _, msgOk := pathMsgs[msgID]; !msgOk { + c.msgMapByPath[pkgPath][msgID] = msg + } + if _, ok := c.msgIDs[getMsgNameWithCrc(msg)]; ok { + return msgID, nil } + c.msgIDs[getMsgNameWithCrc(msg)] = msgID + return msgID, nil +} - chID := uint16(atomic.AddUint32(&c.maxChannelID, 1) & 0x7fff) - ch := &channel{ - id: chID, - replyTimeout: defaultReplyTimeout, - msgDecoder: c.codec, - msgIdentifier: c, - reqChan: make(chan *vppRequest, reqChanBufSize), - replyChan: make(chan *vppReply, replyChanBufSize), - notifSubsChan: make(chan *subscriptionRequest, reqChanBufSize), - notifSubsReplyChan: make(chan error, replyChanBufSize), +// LookupByID looks up message name and crc by ID. +func (c *Connection) LookupByID(path string, msgID uint16) (api.Message, error) { + if c == nil { + return nil, errors.New("nil connection passed in") } + if msg, ok := c.msgMapByPath[path][msgID]; ok { + return msg, nil + } + return nil, fmt.Errorf("unknown message ID %d for path '%s'", msgID, path) +} - // store API channel within the client - c.channelsLock.Lock() - c.channels[chID] = ch - c.channelsLock.Unlock() +// GetMessagePath returns path for the given message +func (c *Connection) GetMessagePath(msg api.Message) string { + return path.Dir(reflect.TypeOf(msg).Elem().PkgPath()) +} - // start watching on the request channel - go c.watchRequests(ch) +// retrieveMessageIDs retrieves IDs for all registered messages and stores them in map +func (c *Connection) retrieveMessageIDs() (err error) { + t := time.Now() - return ch, nil -} + msgsByPath := api.GetRegisteredMessages() -// releaseAPIChannel releases API channel that needs to be closed. -func (c *Connection) releaseAPIChannel(ch *channel) { - log.WithFields(logger.Fields{ - "channel": ch.id, - }).Debug("API channel released") + var n int + for pkgPath, msgs := range msgsByPath { + for _, msg := range msgs { + msgID, err := c.GetMessageID(msg) + if err != nil { + if debugMsgIDs { + log.Debugf("retrieving message ID for %s.%s failed: %v", + pkgPath, msg.GetMessageName(), err) + } + continue + } + n++ + + if c.pingReqID == 0 && msg.GetMessageName() == c.msgControlPing.GetMessageName() { + c.pingReqID = msgID + c.msgControlPing = reflect.New(reflect.TypeOf(msg).Elem()).Interface().(api.Message) + } else if c.pingReplyID == 0 && msg.GetMessageName() == c.msgControlPingReply.GetMessageName() { + c.pingReplyID = msgID + c.msgControlPingReply = reflect.New(reflect.TypeOf(msg).Elem()).Interface().(api.Message) + } - // delete the channel from channels map - c.channelsLock.Lock() - delete(c.channels, ch.id) - c.channelsLock.Unlock() + if debugMsgIDs { + log.Debugf("message %q (%s) has ID: %d", msg.GetMessageName(), getMsgNameWithCrc(msg), msgID) + } + } + log.WithField("took", time.Since(t)). + Debugf("retrieved IDs for %d messages (registered %d) from path %s", n, len(msgs), pkgPath) + } + + return nil +} + +func (c *Connection) sendConnEvent(event ConnectionEvent) { + select { + case c.connChan <- event: + default: + log.Warn("Connection state channel is full, discarding value.") + } }