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1//===-- condition_variable.h ------------------------------------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef SCUDO_CONDITION_VARIABLE_H_10#define SCUDO_CONDITION_VARIABLE_H_11 12#include "condition_variable_base.h"13 14#include "common.h"15#include "platform.h"16 17#include "condition_variable_linux.h"18 19namespace scudo {20 21// A default implementation of default condition variable. It doesn't do a real22// `wait`, instead it spins a short amount of time only.23class ConditionVariableDummy24 : public ConditionVariableBase<ConditionVariableDummy> {25public:26 void notifyAllImpl(UNUSED HybridMutex &M) REQUIRES(M) {}27 28 void waitImpl(UNUSED HybridMutex &M) REQUIRES(M) {29 M.unlock();30 31 constexpr u32 SpinTimes = 64;32 volatile u32 V = 0;33 for (u32 I = 0; I < SpinTimes; ++I) {34 u32 Tmp = V + 1;35 V = Tmp;36 }37 38 M.lock();39 }40};41 42} // namespace scudo43 44#endif // SCUDO_CONDITION_VARIABLE_H_45