c5ef1d6252
This seems to improve parallelism on multicores and at least on Android, doesn't seem to impact performance.
55 lines
1.6 KiB
C++
55 lines
1.6 KiB
C++
/*
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* Copyright (C) 2015 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#include <utils/CountDownLatch.h>
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namespace utils {
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CountDownLatch::CountDownLatch(size_t count) noexcept
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: m_initial_count(static_cast<uint32_t>(count)),
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m_remaining_count(static_cast<uint32_t>(count)) {
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}
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void CountDownLatch::reset(size_t count) noexcept {
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std::lock_guard<Mutex> guard(m_lock);
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m_initial_count = static_cast<uint32_t>(count);
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m_remaining_count = static_cast<uint32_t>(count);
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if (count == 0) {
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m_cv.notify_all();
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}
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}
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void CountDownLatch::await() noexcept {
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std::unique_lock<Mutex> guard(m_lock);
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m_cv.wait(guard, [this]{ return m_remaining_count == 0; } );
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}
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void CountDownLatch::latch() noexcept {
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std::lock_guard<Mutex> guard(m_lock);
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if (m_remaining_count > 0) {
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if (--m_remaining_count == 0) {
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m_cv.notify_all();
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}
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}
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}
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size_t CountDownLatch::getCount() const noexcept {
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std::lock_guard<Mutex> guard(m_lock);
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return m_initial_count - m_remaining_count;
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}
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} // namespace utils
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