/*
 * Copyright (C) 2018 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <utils/linux/Mutex.h>

#include "futex.h"

namespace utils {

void Mutex::wait() noexcept {
    while (UTILS_UNLIKELY(mState.exchange(LOCKED_CONTENDED, std::memory_order_acquire) != UNLOCKED)) {
        linuxutil::futex_wait_ex(&mState, false, LOCKED_CONTENDED, false, nullptr);
    }
}

void Mutex::wake() noexcept {
    linuxutil::futex_wake_ex(&mState, false, LOCKED);
}

} // namespace utils

