More robust solution to close deadlock

This commit is contained in:
Jason A. Donenfeld 2018-05-05 06:00:38 +02:00
parent 09a9bc2899
commit a46401bbb1
3 changed files with 33 additions and 31 deletions

View File

@ -13,6 +13,10 @@ import (
"time"
)
const (
DeviceRoutineNumberPerCPU = 3
)
type Device struct {
isUp AtomicBool // device is (going) up
isClosed AtomicBool // device is closed? (acting as guard)
@ -21,6 +25,7 @@ type Device struct {
// synchronized resources (locks acquired in order)
state struct {
stopping sync.WaitGroup
mutex sync.Mutex
changing AtomicBool
current bool
@ -306,7 +311,9 @@ func NewDevice(tun TUNDevice, logger *Logger) *Device {
// start workers
for i := 0; i < runtime.NumCPU(); i += 1 {
cpus := runtime.NumCPU()
device.state.stopping.Add(DeviceRoutineNumberPerCPU * cpus)
for i := 0; i < cpus; i += 1 {
go device.RoutineEncryption()
go device.RoutineDecryption()
go device.RoutineHandshake()
@ -360,6 +367,25 @@ func (device *Device) RemoveAllPeers() {
device.peers.keyMap = make(map[NoisePublicKey]*Peer)
}
func (device *Device) FlushPacketQueues() {
for {
select {
case elem, ok := <-device.queue.decryption:
if ok {
elem.Drop()
}
case elem, ok := <-device.queue.encryption:
if ok {
elem.Drop()
}
case <-device.queue.handshake:
default:
return
}
}
}
func (device *Device) Close() {
if device.isClosed.Swap(true) {
return
@ -376,6 +402,9 @@ func (device *Device) Close() {
device.signal.stop.Broadcast()
device.state.stopping.Wait()
device.FlushPacketQueues()
device.RemoveAllPeers()
device.rate.limiter.Close()

View File

@ -238,17 +238,7 @@ func (device *Device) RoutineDecryption() {
logDebug := device.log.Debug
defer func() {
for {
select {
case elem, ok := <-device.queue.decryption:
if ok {
elem.Drop()
}
default:
goto out
}
}
out:
device.state.stopping.Done()
logDebug.Println("Routine: decryption worker - stopped")
}()
logDebug.Println("Routine: decryption worker - started")
@ -314,14 +304,7 @@ func (device *Device) RoutineHandshake() {
logDebug := device.log.Debug
defer func() {
for {
select {
case <-device.queue.handshake:
default:
goto out
}
}
out:
device.state.stopping.Done()
logDebug.Println("Routine: handshake worker - stopped")
}()

12
send.go
View File

@ -274,17 +274,7 @@ func (device *Device) RoutineEncryption() {
logDebug := device.log.Debug
defer func() {
for {
select {
case elem, ok := <-device.queue.encryption:
if ok {
elem.Drop()
}
default:
goto out
}
}
out:
device.state.stopping.Done()
logDebug.Println("Routine: encryption worker - stopped")
}()