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