tetragon: Add support to disable uprobe multi through spec options

Adding support to process options passed in spec for uprobe sensor. At the moment the only supported option is to disable uprobe multi. Signed-off-by: Jiri Olsa <[email protected]>
cilium · Mar 30, 2024 · f39de5f · f39de5f
1 parent dce0075
commit f39de5f
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Showing 3 changed files with 22 additions and 5 deletions.
diff --git a/pkg/option/flags.go b/pkg/option/flags.go
@@ -69,6 +69,7 @@ const (
 	KeyNetnsDir = "netns-dir"
 
 	KeyDisableKprobeMulti = "disable-kprobe-multi"
+	KeyDisableUprobeMulti = "disable-uprobe-multi"
 
 	KeyRBSize      = "rb-size"
 	KeyRBSizeTotal = "rb-size-total"

diff --git a/pkg/sensors/tracing/genericuprobe.go b/pkg/sensors/tracing/genericuprobe.go
@@ -251,22 +251,31 @@ type addUprobeIn struct {
 
 func createGenericUprobeSensor(
 	name string,
-	uprobes []v1alpha1.UProbeSpec,
+	spec *v1alpha1.TracingPolicySpec,
 	policyName string,
 ) (*sensors.Sensor, error) {
 	var progs []*program.Program
 	var maps []*program.Map
 	var ids []idtable.EntryID
 	var err error
 
+	options, err := getSpecOptions(spec.Options)
+	if err != nil {
+		return nil, fmt.Errorf("failed to set options: %s", err)
+	}
+
 	in := addUprobeIn{
 		sensorPath: name,
 		policyName: policyName,
-		useMulti:   bpf.HasUprobeMulti(),
+
+		// use multi kprobe only if:
+		// - it's not disabled by spec option
+		// - there's support detected
+		useMulti: !options.DisableUprobeMulti && bpf.HasUprobeMulti(),
 	}
 
-	for _, spec := range uprobes {
-		ids, err = addUprobe(&spec, ids, &in)
+	for _, uprobe := range spec.UProbes {
+		ids, err = addUprobe(&uprobe, ids, &in)
 		if err != nil {
 			return nil, err
 		}
@@ -489,5 +498,5 @@ func (k *observerUprobeSensor) PolicyHandler(
 
 	name := fmt.Sprintf("gup-sensor-%d", atomic.AddUint64(&sensorCounter, 1))
 	policyName := p.TpName()
-	return createGenericUprobeSensor(name, spec.UProbes, policyName)
+	return createGenericUprobeSensor(name, spec, policyName)
 }
diff --git a/pkg/sensors/tracing/options.go b/pkg/sensors/tracing/options.go
@@ -40,6 +40,7 @@ func overrideMethodParse(s string) OverrideMethod {
 
 type specOptions struct {
 	DisableKprobeMulti bool
+	DisableUprobeMulti bool
 	OverrideMethod     OverrideMethod
 }
 
@@ -62,6 +63,12 @@ var opts = map[string]opt{
 			return err
 		},
 	},
+	option.KeyDisableUprobeMulti: opt{
+		set: func(str string, options *specOptions) (err error) {
+			options.DisableUprobeMulti, err = strconv.ParseBool(str)
+			return err
+		},
+	},
 	keyOverrideMethod: opt{
 		set: func(str string, options *specOptions) (err error) {
 			m := overrideMethodParse(str)