tetragon: Use ebpf/cilium feature test for bpf_send_signal

Signed-off-by: Jiri Olsa <jolsa@kernel.org>

pkg/bpf/detect.go

@@ -24,7 +24,6 @@ type Feature struct {
 }
 
 var (
-	signalHelper     Feature
 	kprobeMulti      Feature
 	buildid          Feature
 	modifyReturn     Feature
@@ -35,29 +34,8 @@ func HasOverrideHelper() bool {
 	return features.HaveProgramHelper(ebpf.Kprobe, asm.FnOverrideReturn) == nil
 }
 
-func detectSignalHelper() bool {
-	prog, err := ebpf.NewProgram(&ebpf.ProgramSpec{
-		Type: ebpf.Kprobe,
-		Instructions: asm.Instructions{
-			asm.LoadImm(asm.R2, 2, asm.DWord),
-			asm.Instruction{OpCode: asm.OpCode(asm.JumpClass).SetJumpOp(asm.Call), Constant: 109},
-			asm.LoadImm(asm.R0, 0, asm.DWord),
-			asm.Return(),
-		},
-		License: "GPL",
-	})
-	if err != nil {
-		return false
-	}
-	prog.Close()
-	return true
-}
-
 func HasSignalHelper() bool {
-	signalHelper.init.Do(func() {
-		signalHelper.detected = detectSignalHelper()
-	})
-	return signalHelper.detected
+	return features.HaveProgramHelper(ebpf.Kprobe, asm.FnSendSignal) == nil
 }
 
 func detectKprobeMulti() bool {