1 files changed, 52 insertions, 0 deletions
diff --git a/tools/checklocks/test/rwmutex.go b/tools/checklocks/test/rwmutex.go
new file mode 100644
index 000000000..d27ed10e3
--- /dev/null
+++ b/tools/checklocks/test/rwmutex.go
@@ -0,0 +1,52 @@
+// Copyright 2021 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package test
+
+import (
+	"sync"
+)
+
+// oneReadGuardStruct has one read-guarded field.
+type oneReadGuardStruct struct {
+	mu sync.RWMutex
+	// +checklocks:mu
+	guardedField int
+}
+
+func testRWAccessValidRead(tc *oneReadGuardStruct) {
+	tc.mu.Lock()
+	_ = tc.guardedField
+	tc.mu.Unlock()
+	tc.mu.RLock()
+	_ = tc.guardedField
+	tc.mu.RUnlock()
+}
+
+func testRWAccessValidWrite(tc *oneReadGuardStruct) {
+	tc.mu.Lock()
+	tc.guardedField = 1
+	tc.mu.Unlock()
+}
+
+func testRWAccessInvalidWrite(tc *oneReadGuardStruct) {
+	tc.guardedField = 2 // +checklocksfail
+	tc.mu.RLock()
+	tc.guardedField = 2 // +checklocksfail
+	tc.mu.RUnlock()
+}
+
+func testRWAccessInvalidRead(tc *oneReadGuardStruct) {
+	_ = tc.guardedField // +checklocksfail
+}