gvisor.dev/gvisor@v0.0.0-20240520182842-f9d4d51c7e0f/tools/checklocks/test/rwmutex.go (about)

     1  // Copyright 2021 The gVisor Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package test
    16  
    17  import (
    18  	"sync"
    19  )
    20  
    21  // oneReadGuardStruct has one read-guarded field.
    22  type oneReadGuardStruct struct {
    23  	mu sync.RWMutex
    24  	// +checklocks:mu
    25  	guardedField int
    26  }
    27  
    28  func testRWAccessValidRead(tc *oneReadGuardStruct) {
    29  	tc.mu.Lock()
    30  	_ = tc.guardedField
    31  	tc.mu.Unlock()
    32  	tc.mu.RLock()
    33  	_ = tc.guardedField
    34  	tc.mu.RUnlock()
    35  }
    36  
    37  func testRWAccessValidWrite(tc *oneReadGuardStruct) {
    38  	tc.mu.Lock()
    39  	tc.guardedField = 1
    40  	tc.mu.Unlock()
    41  }
    42  
    43  func testRWAccessInvalidWrite(tc *oneReadGuardStruct) {
    44  	tc.guardedField = 2 // +checklocksfail
    45  	tc.mu.RLock()
    46  	tc.guardedField = 2 // +checklocksfail
    47  	tc.mu.RUnlock()
    48  }
    49  
    50  func testRWAccessInvalidRead(tc *oneReadGuardStruct) {
    51  	_ = tc.guardedField // +checklocksfail
    52  }