File: lock_subtle.h

package info (click to toggle)
chromium 139.0.7258.127-1
  • links: PTS, VCS
  • area: main
  • in suites:
  • size: 6,122,068 kB
  • sloc: cpp: 35,100,771; ansic: 7,163,530; javascript: 4,103,002; python: 1,436,920; asm: 946,517; xml: 746,709; pascal: 187,653; perl: 88,691; sh: 88,436; objc: 79,953; sql: 51,488; cs: 44,583; fortran: 24,137; makefile: 22,147; tcl: 15,277; php: 13,980; yacc: 8,984; ruby: 7,485; awk: 3,720; lisp: 3,096; lex: 1,327; ada: 727; jsp: 228; sed: 36
file content (43 lines) | stat: -rw-r--r-- 1,547 bytes parent folder | download | duplicates (6)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
// Copyright 2024 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef BASE_SYNCHRONIZATION_LOCK_SUBTLE_H_
#define BASE_SYNCHRONIZATION_LOCK_SUBTLE_H_

#include "base/base_export.h"
#include "base/containers/span.h"
#include "base/dcheck_is_on.h"

namespace base::subtle {

#if DCHECK_IS_ON()
// Returns addresses of locks acquired by the current thread with
// `subtle::LockTracking::kEnabled`. `uintptr_t` is used because addresses are
// meant to be used as unique identifiers but not to be dereferenced.
BASE_EXPORT span<const uintptr_t> GetTrackedLocksHeldByCurrentThread();
#endif

// Whether to add a lock to the list returned by
// `subtle::GetLocksHeldByCurrentThread()` upon acquisition. This has no effect
// in non-DCHECK builds because tracking is always disabled. This is disabled by
// default to avoid exceeding the fixed-size storage backing
// `GetTrackedLocksHeldByCurrentThread()` and to avoid reentrancy, e.g.:
//
//     thread_local implementation
//     Add lock to the thread_local array of locks held by current thread
//     base::Lock::Acquire from allocator shim
//     ... Allocator shim ...
//     thread_local implementation
//     Access to a thread_local variable
//
// A lock acquired with `subtle::LockTracking::kEnabled` can be used to provide
// a mutual exclusion guarantee for SEQUENCE_CHECKER.
enum class LockTracking {
  kDisabled,
  kEnabled,
};

}  // namespace base::subtle

#endif  // BASE_SYNCHRONIZATION_LOCK_SUBTLE_H_