dawn-cmake/third_party/abseil-cpp/absl/base/internal/spinlock_posix.inc

47 lines
1.4 KiB
C++

// Copyright 2017 The Abseil Authors.
//
// 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
//
// https://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.
//
// This file is a Posix-specific part of spinlock_wait.cc
#include <sched.h>
#include <atomic>
#include <ctime>
#include "absl/base/internal/errno_saver.h"
#include "absl/base/internal/scheduling_mode.h"
#include "absl/base/port.h"
extern "C" {
ABSL_ATTRIBUTE_WEAK void ABSL_INTERNAL_C_SYMBOL(AbslInternalSpinLockDelay)(
std::atomic<uint32_t>* /* lock_word */, uint32_t /* value */, int loop,
absl::base_internal::SchedulingMode /* mode */) {
absl::base_internal::ErrnoSaver errno_saver;
if (loop == 0) {
} else if (loop == 1) {
sched_yield();
} else {
struct timespec tm;
tm.tv_sec = 0;
tm.tv_nsec = absl::base_internal::SpinLockSuggestedDelayNS(loop);
nanosleep(&tm, nullptr);
}
}
ABSL_ATTRIBUTE_WEAK void ABSL_INTERNAL_C_SYMBOL(AbslInternalSpinLockWake)(
std::atomic<uint32_t>* /* lock_word */, bool /* all */) {}
} // extern "C"