Add unit test

pkg/internal/ebpf/tracer_linux.go

@@ -44,6 +44,10 @@ func roundToNearestMultiple(x, n uint32) uint32 {
 		return n
 	}
 
+	if x%n == 0 {
+		return x
+	}
+
 	return (x + n/2) / n * n
 }
 

pkg/internal/ebpf/tracer_linux_test.go

@@ -0,0 +1,32 @@
+package ebpf
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestRoundToNearestMultiple(t *testing.T) {
+	tests := []struct {
+		x, n, expected uint32
+	}{
+		{0, 5, 5},   // x < n, should return n
+		{3, 5, 5},   // x < n, should return n
+		{5, 5, 5},   // x == n, should return n (no rounding needed)
+		{6, 5, 5},   // x > n, should round down
+		{7, 5, 5},   // x > n, should round down
+		{12, 5, 10}, // x > n, should round down
+		{13, 5, 15}, // x > n, should round up
+		{9, 7, 7},   // x < n, should return n
+		{10, 7, 7},  // x == n, should return n
+		{11, 7, 14}, // x > n, should round to the nearest multiple
+	}
+
+	for _, tt := range tests {
+		t.Run(fmt.Sprintf("x=%d, n=%d", tt.x, tt.n), func(t *testing.T) {
+			got := roundToNearestMultiple(tt.x, tt.n)
+			if got != tt.expected {
+				t.Errorf("roundToNearestMultiple(%d, %d) = %d; want %d", tt.x, tt.n, got, tt.expected)
+			}
+		})
+	}
+}