github.com/cockroachdb/cockroachdb-parser@v0.23.3-0.20240213214944-911057d40c9a/pkg/util/syncutil/mutex_sync.go (about)

     1  // Copyright 2016 The Cockroach Authors.
     2  //
     3  // Use of this software is governed by the Business Source License
     4  // included in the file licenses/BSL.txt.
     5  //
     6  // As of the Change Date specified in that file, in accordance with
     7  // the Business Source License, use of this software will be governed
     8  // by the Apache License, Version 2.0, included in the file
     9  // licenses/APL.txt.
    10  
    11  //go:build !deadlock && !race
    12  // +build !deadlock,!race
    13  
    14  package syncutil
    15  
    16  import "sync"
    17  
    18  // DeadlockEnabled is true if the deadlock detector is enabled.
    19  const DeadlockEnabled = false
    20  
    21  // A Mutex is a mutual exclusion lock.
    22  type Mutex struct {
    23  	sync.Mutex
    24  }
    25  
    26  // AssertHeld may panic if the mutex is not locked (but it is not required to
    27  // do so). Functions which require that their callers hold a particular lock
    28  // may use this to enforce this requirement more directly than relying on the
    29  // race detector.
    30  //
    31  // Note that we do not require the lock to be held by any particular thread,
    32  // just that some thread holds the lock. This is both more efficient and allows
    33  // for rare cases where a mutex is locked in one thread and used in another.
    34  func (m *Mutex) AssertHeld() {
    35  }
    36  
    37  // An RWMutex is a reader/writer mutual exclusion lock.
    38  type RWMutex struct {
    39  	sync.RWMutex
    40  }
    41  
    42  // AssertHeld may panic if the mutex is not locked for writing (but it is not
    43  // required to do so). Functions which require that their callers hold a
    44  // particular lock may use this to enforce this requirement more directly than
    45  // relying on the race detector.
    46  //
    47  // Note that we do not require the exclusive lock to be held by any particular
    48  // thread, just that some thread holds the lock. This is both more efficient
    49  // and allows for rare cases where a mutex is locked in one thread and used in
    50  // another.
    51  func (rw *RWMutex) AssertHeld() {
    52  }
    53  
    54  // AssertRHeld may panic if the mutex is not locked for reading (but it is not
    55  // required to do so). If the mutex is locked for writing, it is also considered
    56  // to be locked for reading. Functions which require that their callers hold a
    57  // particular lock may use this to enforce this requirement more directly than
    58  // relying on the race detector.
    59  //
    60  // Note that we do not require the shared lock to be held by any particular
    61  // thread, just that some thread holds the lock. This is both more efficient
    62  // and allows for rare cases where a mutex is locked in one thread and used in
    63  // another.
    64  func (rw *RWMutex) AssertRHeld() {
    65  }