pkg/runtest: allow to select a subset of tests to run

pkg/runtest/run_test.go

@@ -4,6 +4,7 @@
 package runtest
 
 import (
+	"flag"
 	"os"
 	"path/filepath"
 	"runtime"
@@ -16,6 +17,11 @@ import (
 	_ "github.com/google/syzkaller/sys/test/gen" // pull in the test target
 )
 
+// Can be used as:
+// go test -v -run=Test/64_fork ./pkg/runtest -filter=nonfailing
+// to select a subset of tests to run.
+var flagFilter = flag.String("filter", "", "prefix to match test file names")
+
 func Test(t *testing.T) {
 	switch runtime.GOOS {
 	case "openbsd":
@@ -74,6 +80,7 @@ func test(t *testing.T, sysTarget *targets.Target) {
 	ctx := &Context{
 		Dir:          filepath.Join("..", "..", "sys", target.OS, "test"),
 		Target:       target,
+		Tests:        *flagFilter,
 		Features:     features,
 		EnabledCalls: enabledCalls,
 		Requests:     requests,