tunnel: def runid waiting on the endpoint

Author: ignoramous

intra/core/async.go

@@ -225,9 +225,9 @@ func Periodic(id string, pctx context.Context, d time.Duration, f func()) contex
 }
 
 // SigFin runs f in a goroutine and returns a channel that is closed when f returns.
-func SigFin(f func()) <-chan struct{} {
+func SigFin(id string, f func()) <-chan struct{} {
 	done := make(chan struct{})
-	Go("take", func() {
+	Go("sigfin."+id, func() {
 		defer close(done)
 		f()
 	})

intra/netstack/fdbased.go

@@ -380,7 +380,7 @@ func (e *endpoint) Attach(dispatcher stack.NetworkDispatcher) {
 
 // IsAttached implements stack.LinkEndpoint.IsAttached.
 func (e *endpoint) IsAttached() bool {
-	d, _ := e.getDispatcher()
+	d, _ := e.getDispatchers()
 	return d != nil
 }
 
@@ -574,15 +574,15 @@ func (e *endpoint) SetMTU(mtu uint32) {
 	e.mtu.Store(mtu)
 }
 
-func (e *endpoint) getDispatcher() (stack.NetworkDispatcher, *fds) {
+func (e *endpoint) getDispatchers() (stack.NetworkDispatcher, *fds) {
 	e.RLock()
 	defer e.RUnlock()
 	return e.dispatcher, e.fds.Load()
 }
 
 // InjectInbound ingresses a netstack-inbound packet.
 func (e *endpoint) InjectInbound(protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) {
-	d, fds := e.getDispatcher()
+	d, fds := e.getDispatchers()
 	fd := fds.tun()
 	log.VV("ns: tun(%d): inject-inbound (from tun) %d", fd, protocol)
 	if d != nil && pkt != nil {

tunnel/tunnel.go

@@ -29,6 +29,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"strconv"
 	"sync"
 	"sync/atomic"
 	"syscall"
@@ -108,13 +109,14 @@ func (t *gtunnel) waitForEndpoint(ctx context.Context) {
 		// wait a bit to let the endpoint settle
 		time.Sleep(betweenChecks)
 		start := time.Now()
+		runid := "g." + strconv.Itoa(i)
 
 		select {
 		case <-ctx.Done():
 			t.Disconnect() // may already be disconnected
 			log.D("tun: waiter: ctx done; #%d", i)
 			return
-		case <-core.SigFin(t.ep.Wait): // wait until endpoint closes
+		case <-core.SigFin(runid, t.ep.Wait): // wait until endpoint closes
 			log.D("tun: waiter: endpoint not running; #%d", i)
 		}