Remove id from sleep.Sleeper API.

In a subsequent change, the Sleeper API will be plumbed through and used for
arbitrary task wakeups. This requires a non-static association of Wakers and
Sleepers, which means that a fixed ID no longer works. This is a relatively
simple change that removes the ID from the Waker association, and simply uses
the Waker pointer itself.

That change also makes minor improvements to the tests to ensure that the
benchmarks are more representative by removing goroutine start from the hot
path (and uses Wakers for required synchronization), adds assertion checks to
AddWaker, and clears relevant fields during Done (to allow assertions to pass).

PiperOrigin-RevId: 407719630

1 files changed, 5 insertions, 6 deletions

diff --git a/pkg/tcpip/link/qdisc/fifo/endpoint.go b/pkg/tcpip/link/qdisc/fifo/endpoint.go
index b41e3e2fa..c15cbf81b 100644
--- a/pkg/tcpip/link/qdisc/fifo/endpoint.go
+++ b/pkg/tcpip/link/qdisc/fifo/endpoint.go
@@ -73,20 +73,19 @@ func New(lower stack.LinkEndpoint, n int, queueLen int) stack.LinkEndpoint {
 }
 
 func (q *queueDispatcher) dispatchLoop() {
-	const newPacketWakerID = 1
-	const closeWakerID = 2
 	s := sleep.Sleeper{}
-	s.AddWaker(&q.newPacketWaker, newPacketWakerID)
-	s.AddWaker(&q.closeWaker, closeWakerID)
+	s.AddWaker(&q.newPacketWaker)
+	s.AddWaker(&q.closeWaker)
 	defer s.Done()
 
 	const batchSize = 32
 	var batch stack.PacketBufferList
 	for {
-		id, ok := s.Fetch(true)
-		if ok && id == closeWakerID {
+		w := s.Fetch(true)
+		if w == &q.closeWaker {
 			return
 		}
+		// Must otherwise be the newPacketWaker.
 		for pkt := q.q.dequeue(); pkt != nil; pkt = q.q.dequeue() {
 			batch.PushBack(pkt)
 			if batch.Len() < batchSize && !q.q.empty() {