fix: rb.stopped should be set in the Stop method

This cleans up the design of a solution to an issue where Stop()
 could be called after the sole consumer of the rb.stop channel
 has closed but rb.stopped has not yet been set. This removes
the need to have a non-blocking channel write with `select` as
it turns out we really don't need this channel at all.

Signed-off-by: grantseltzer <grantseltzer@gmail.com>

libbpfgo/libbpfgo.go

@@ -231,7 +231,6 @@ type PerfBuffer struct {
 type RingBuffer struct {
 	rb      *C.struct_ring_buffer
 	bpfMap  *BPFMap
-	stop    chan bool
 	stopped bool
 	closed bool 
 }
@@ -643,24 +642,18 @@ func (m *Module) InitRingBuf(mapName string, eventsChan chan []byte) (*RingBuffe
 	ringBuf := &RingBuffer{
 		rb:     rb,
 		bpfMap: bpfMap,
-		stop:   make(chan bool),
 	}
 	m.ringBufs = append(m.ringBufs, ringBuf)
 	return ringBuf, nil
 }
 
 func (rb *RingBuffer) Start() {
 	go rb.poll()
+	rb.stopped = false
 }
 
 func (rb *RingBuffer) Stop() {
-	if rb.stopped {
-		return
-	}
-	select {
-	case rb.stop <- true:
-	default:
-	}
+	rb.stopped = true
 }
 
 func (rb *RingBuffer) Close() {
@@ -676,11 +669,6 @@ func (rb *RingBuffer) Close() {
 
 func (rb *RingBuffer) poll() error {
 
-	go func() {
-		<-rb.stop
-		rb.stopped = true
-	}()
-
 	for {
 		err := C.ring_buffer__poll(rb.rb, 0)
 		if err < 0 {