| // Copyright (c) 2011 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "base/synchronization/atomic_flag.h" |
| |
| #include "base/logging.h" |
| |
| namespace base { |
| |
| AtomicFlag::AtomicFlag() { |
| // It doesn't matter where the AtomicFlag is built so long as it's always |
| // Set() from the same sequence after. Note: the sequencing requirements are |
| // necessary for IsSet()'s callers to know which sequence's memory operations |
| // they are synchronized with. |
| set_sequence_checker_.DetachFromSequence(); |
| } |
| |
| void AtomicFlag::Set() { |
| DCHECK(set_sequence_checker_.CalledOnValidSequence()); |
| base::subtle::Release_Store(&flag_, 1); |
| } |
| |
| bool AtomicFlag::IsSet() const { |
| return base::subtle::Acquire_Load(&flag_) != 0; |
| } |
| |
| void AtomicFlag::UnsafeResetForTesting() { |
| base::subtle::Release_Store(&flag_, 0); |
| } |
| |
| } // namespace base |