les: handle conn/disc/reg logic in the eventloop (#16981)

* les: handle conn/disc/reg logic in the eventloop

* les: try to dial before start eventloop

* les: handle disconnect logic more safely

* les: grammar fix
This commit is contained in:
gary rong 2018-06-25 16:52:25 +08:00 committed by Péter Szilágyi
parent eaff89291c
commit 4895665670

@ -87,6 +87,27 @@ const (
initStatsWeight = 1
)
// connReq represents a request for peer connection.
type connReq struct {
p *peer
ip net.IP
port uint16
result chan *poolEntry
}
// disconnReq represents a request for peer disconnection.
type disconnReq struct {
entry *poolEntry
stopped bool
done chan struct{}
}
// registerReq represents a request for peer registration.
type registerReq struct {
entry *poolEntry
done chan struct{}
}
// serverPool implements a pool for storing and selecting newly discovered and already
// known light server nodes. It received discovered nodes, stores statistics about
// known nodes and takes care of always having enough good quality servers connected.
@ -105,10 +126,13 @@ type serverPool struct {
discLookups chan bool
entries map[discover.NodeID]*poolEntry
lock sync.Mutex
timeout, enableRetry chan *poolEntry
adjustStats chan poolStatAdjust
connCh chan *connReq
disconnCh chan *disconnReq
registerCh chan *registerReq
knownQueue, newQueue poolEntryQueue
knownSelect, newSelect *weightedRandomSelect
knownSelected, newSelected int
@ -125,6 +149,9 @@ func newServerPool(db ethdb.Database, quit chan struct{}, wg *sync.WaitGroup) *s
timeout: make(chan *poolEntry, 1),
adjustStats: make(chan poolStatAdjust, 100),
enableRetry: make(chan *poolEntry, 1),
connCh: make(chan *connReq),
disconnCh: make(chan *disconnReq),
registerCh: make(chan *registerReq),
knownSelect: newWeightedRandomSelect(),
newSelect: newWeightedRandomSelect(),
fastDiscover: true,
@ -147,9 +174,8 @@ func (pool *serverPool) start(server *p2p.Server, topic discv5.Topic) {
pool.discLookups = make(chan bool, 100)
go pool.server.DiscV5.SearchTopic(pool.topic, pool.discSetPeriod, pool.discNodes, pool.discLookups)
}
go pool.eventLoop()
pool.checkDial()
go pool.eventLoop()
}
// connect should be called upon any incoming connection. If the connection has been
@ -158,83 +184,44 @@ func (pool *serverPool) start(server *p2p.Server, topic discv5.Topic) {
// Note that whenever a connection has been accepted and a pool entry has been returned,
// disconnect should also always be called.
func (pool *serverPool) connect(p *peer, ip net.IP, port uint16) *poolEntry {
pool.lock.Lock()
defer pool.lock.Unlock()
entry := pool.entries[p.ID()]
if entry == nil {
entry = pool.findOrNewNode(p.ID(), ip, port)
}
p.Log().Debug("Connecting to new peer", "state", entry.state)
if entry.state == psConnected || entry.state == psRegistered {
log.Debug("Connect new entry", "enode", p.id)
req := &connReq{p: p, ip: ip, port: port, result: make(chan *poolEntry, 1)}
select {
case pool.connCh <- req:
case <-pool.quit:
return nil
}
pool.connWg.Add(1)
entry.peer = p
entry.state = psConnected
addr := &poolEntryAddress{
ip: ip,
port: port,
lastSeen: mclock.Now(),
}
entry.lastConnected = addr
entry.addr = make(map[string]*poolEntryAddress)
entry.addr[addr.strKey()] = addr
entry.addrSelect = *newWeightedRandomSelect()
entry.addrSelect.update(addr)
return entry
return <-req.result
}
// registered should be called after a successful handshake
func (pool *serverPool) registered(entry *poolEntry) {
log.Debug("Registered new entry", "enode", entry.id)
pool.lock.Lock()
defer pool.lock.Unlock()
entry.state = psRegistered
entry.regTime = mclock.Now()
if !entry.known {
pool.newQueue.remove(entry)
entry.known = true
req := &registerReq{entry: entry, done: make(chan struct{})}
select {
case pool.registerCh <- req:
case <-pool.quit:
return
}
pool.knownQueue.setLatest(entry)
entry.shortRetry = shortRetryCnt
<-req.done
}
// disconnect should be called when ending a connection. Service quality statistics
// can be updated optionally (not updated if no registration happened, in this case
// only connection statistics are updated, just like in case of timeout)
func (pool *serverPool) disconnect(entry *poolEntry) {
log.Debug("Disconnected old entry", "enode", entry.id)
pool.lock.Lock()
defer pool.lock.Unlock()
if entry.state == psRegistered {
connTime := mclock.Now() - entry.regTime
connAdjust := float64(connTime) / float64(targetConnTime)
if connAdjust > 1 {
connAdjust = 1
}
stopped := false
select {
case <-pool.quit:
stopped = true
default:
}
if stopped {
entry.connectStats.add(1, connAdjust)
} else {
entry.connectStats.add(connAdjust, 1)
}
}
log.Debug("Disconnected old entry", "enode", entry.id)
req := &disconnReq{entry: entry, stopped: stopped, done: make(chan struct{})}
entry.state = psNotConnected
if entry.knownSelected {
pool.knownSelected--
} else {
pool.newSelected--
}
pool.setRetryDial(entry)
pool.connWg.Done()
// Block until disconnection request is served.
pool.disconnCh <- req
<-req.done
}
const (
@ -277,25 +264,51 @@ func (pool *serverPool) eventLoop() {
if pool.discSetPeriod != nil {
pool.discSetPeriod <- time.Millisecond * 100
}
// disconnect updates service quality statistics depending on the connection time
// and disconnection initiator.
disconnect := func(req *disconnReq, stopped bool) {
// Handle peer disconnection requests.
entry := req.entry
if entry.state == psRegistered {
connAdjust := float64(mclock.Now()-entry.regTime) / float64(targetConnTime)
if connAdjust > 1 {
connAdjust = 1
}
if stopped {
// disconnect requested by ourselves.
entry.connectStats.add(1, connAdjust)
} else {
// disconnect requested by server side.
entry.connectStats.add(connAdjust, 1)
}
}
entry.state = psNotConnected
if entry.knownSelected {
pool.knownSelected--
} else {
pool.newSelected--
}
pool.setRetryDial(entry)
pool.connWg.Done()
close(req.done)
}
for {
select {
case entry := <-pool.timeout:
pool.lock.Lock()
if !entry.removed {
pool.checkDialTimeout(entry)
}
pool.lock.Unlock()
case entry := <-pool.enableRetry:
pool.lock.Lock()
if !entry.removed {
entry.delayedRetry = false
pool.updateCheckDial(entry)
}
pool.lock.Unlock()
case adj := <-pool.adjustStats:
pool.lock.Lock()
switch adj.adjustType {
case pseBlockDelay:
adj.entry.delayStats.add(float64(adj.time), 1)
@ -305,13 +318,10 @@ func (pool *serverPool) eventLoop() {
case pseResponseTimeout:
adj.entry.timeoutStats.add(1, 1)
}
pool.lock.Unlock()
case node := <-pool.discNodes:
pool.lock.Lock()
entry := pool.findOrNewNode(discover.NodeID(node.ID), node.IP, node.TCP)
pool.updateCheckDial(entry)
pool.lock.Unlock()
case conv := <-pool.discLookups:
if conv {
@ -327,15 +337,66 @@ func (pool *serverPool) eventLoop() {
}
}
case req := <-pool.connCh:
// Handle peer connection requests.
entry := pool.entries[req.p.ID()]
if entry == nil {
entry = pool.findOrNewNode(req.p.ID(), req.ip, req.port)
}
if entry.state == psConnected || entry.state == psRegistered {
req.result <- nil
continue
}
pool.connWg.Add(1)
entry.peer = req.p
entry.state = psConnected
addr := &poolEntryAddress{
ip: req.ip,
port: req.port,
lastSeen: mclock.Now(),
}
entry.lastConnected = addr
entry.addr = make(map[string]*poolEntryAddress)
entry.addr[addr.strKey()] = addr
entry.addrSelect = *newWeightedRandomSelect()
entry.addrSelect.update(addr)
req.result <- entry
case req := <-pool.registerCh:
// Handle peer registration requests.
entry := req.entry
entry.state = psRegistered
entry.regTime = mclock.Now()
if !entry.known {
pool.newQueue.remove(entry)
entry.known = true
}
pool.knownQueue.setLatest(entry)
entry.shortRetry = shortRetryCnt
close(req.done)
case req := <-pool.disconnCh:
// Handle peer disconnection requests.
disconnect(req, req.stopped)
case <-pool.quit:
if pool.discSetPeriod != nil {
close(pool.discSetPeriod)
}
// Spawn a goroutine to close the disconnCh after all connections are disconnected.
go func() {
pool.connWg.Wait()
close(pool.disconnCh)
}()
// Handle all remaining disconnection requests before exit.
for req := range pool.disconnCh {
disconnect(req, true)
}
pool.saveNodes()
pool.wg.Done()
return
}
}
}