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

     1  // Copyright 2020 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  func testClosureInvalid(tc *oneGuardStruct) {
    18  	// This is expected to fail.
    19  	callClosure(func() {
    20  		tc.guardedField = 1 // +checklocksfail
    21  	})
    22  }
    23  
    24  func testClosureUnsupported(tc *oneGuardStruct) {
    25  	// Locked outside the closure, so may or may not be valid. This cannot
    26  	// be handled and we should explicitly fail. This can't be handled
    27  	// because of the call through callClosure, below, which means the
    28  	// closure will actually be passed as a value somewhere.
    29  	tc.mu.Lock()
    30  	callClosure(func() {
    31  		tc.guardedField = 1 // +checklocksfail
    32  	})
    33  	tc.mu.Unlock()
    34  }
    35  
    36  func testClosureValid(tc *oneGuardStruct) {
    37  	// All locking happens within the closure. This should not present a
    38  	// problem for analysis.
    39  	callClosure(func() {
    40  		tc.mu.Lock()
    41  		tc.guardedField = 1
    42  		tc.mu.Unlock()
    43  	})
    44  }
    45  
    46  func testClosureInline(tc *oneGuardStruct) {
    47  	// If the closure is being dispatching inline only, then we should be
    48  	// able to analyze this call and give it a thumbs up.
    49  	tc.mu.Lock()
    50  	func() {
    51  		tc.guardedField = 1
    52  	}()
    53  	tc.mu.Unlock()
    54  }
    55  
    56  // +checklocksignore
    57  func testClosureIgnore(tc *oneGuardStruct) {
    58  	// Inherit the checklocksignore.
    59  	x := func() {
    60  		tc.guardedField = 1
    61  	}
    62  	x()
    63  }
    64  
    65  func testAnonymousInvalid(tc *oneGuardStruct) {
    66  	// Invalid, as per testClosureInvalid above.
    67  	callAnonymous(func(tc *oneGuardStruct) {
    68  		tc.guardedField = 1 // +checklocksfail
    69  	}, tc)
    70  }
    71  
    72  func testAnonymousUnsupported(tc *oneGuardStruct) {
    73  	// Not supportable, as per testClosureUnsupported above.
    74  	tc.mu.Lock()
    75  	callAnonymous(func(tc *oneGuardStruct) {
    76  		tc.guardedField = 1 // +checklocksfail
    77  	}, tc)
    78  	tc.mu.Unlock()
    79  }
    80  
    81  func testAnonymousValid(tc *oneGuardStruct) {
    82  	// Valid, as per testClosureValid above.
    83  	callAnonymous(func(tc *oneGuardStruct) {
    84  		tc.mu.Lock()
    85  		tc.guardedField = 1
    86  		tc.mu.Unlock()
    87  	}, tc)
    88  }
    89  
    90  func testAnonymousInline(tc *oneGuardStruct) {
    91  	// Unlike the closure case, we are able to dynamically infer the set of
    92  	// preconditions for the function dispatch and assert that this is
    93  	// a valid call.
    94  	tc.mu.Lock()
    95  	func(tc *oneGuardStruct) {
    96  		tc.guardedField = 1
    97  	}(tc)
    98  	tc.mu.Unlock()
    99  }
   100  
   101  // +checklocksignore
   102  func testAnonymousIgnore(tc *oneGuardStruct) {
   103  	// Inherit the checklocksignore.
   104  	x := func(tc *oneGuardStruct) {
   105  		tc.guardedField = 1
   106  	}
   107  	x(tc)
   108  }
   109  
   110  //go:noinline
   111  func callClosure(fn func()) {
   112  	fn()
   113  }
   114  
   115  //go:noinline
   116  func callAnonymous(fn func(*oneGuardStruct), tc *oneGuardStruct) {
   117  	fn(tc)
   118  }