1// Copyright 2017 The Abseil Authors. 2// 3// Licensed under the Apache License, Version 2.0 (the "License"); 4// you may not use this file except in compliance with the License. 5// You may obtain a copy of the License at 6// 7// https://www.apache.org/licenses/LICENSE-2.0 8// 9// Unless required by applicable law or agreed to in writing, software 10// distributed under the License is distributed on an "AS IS" BASIS, 11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12// See the License for the specific language governing permissions and 13// limitations under the License. 14// 15// This file is a Posix-specific part of spinlock_wait.cc 16 17#include <sched.h> 18 19#include <atomic> 20#include <ctime> 21 22#include "absl/base/internal/errno_saver.h" 23#include "absl/base/internal/scheduling_mode.h" 24#include "absl/base/port.h" 25 26extern "C" { 27 28ABSL_ATTRIBUTE_WEAK void AbslInternalSpinLockDelay( 29 std::atomic<uint32_t>* /* lock_word */, uint32_t /* value */, int loop, 30 absl::base_internal::SchedulingMode /* mode */) { 31 absl::base_internal::ErrnoSaver errno_saver; 32 if (loop == 0) { 33 } else if (loop == 1) { 34 sched_yield(); 35 } else { 36 struct timespec tm; 37 tm.tv_sec = 0; 38 tm.tv_nsec = absl::base_internal::SpinLockSuggestedDelayNS(loop); 39 nanosleep(&tm, nullptr); 40 } 41} 42 43ABSL_ATTRIBUTE_WEAK void AbslInternalSpinLockWake( 44 std::atomic<uint32_t>* /* lock_word */, bool /* all */) {} 45 46} // extern "C" 47