#ifndef BENCHMARK_THREAD_TIMER_H #define BENCHMARK_THREAD_TIMER_H #include "check.h" #include "timers.h" namespace benchmark { namespace internal { class ThreadTimer { explicit ThreadTimer(bool measure_process_cpu_time_) : measure_process_cpu_time(measure_process_cpu_time_) {} public: static ThreadTimer Create() { return ThreadTimer(/*measure_process_cpu_time_=*/false); } static ThreadTimer CreateProcessCpuTime() { return ThreadTimer(/*measure_process_cpu_time_=*/true); } // Called by each thread void StartTimer() { running_ = true; start_real_time_ = ChronoClockNow(); start_cpu_time_ = ReadCpuTimerOfChoice(); } // Called by each thread void StopTimer() { BM_CHECK(running_); running_ = false; real_time_used_ += ChronoClockNow() - start_real_time_; // Floating point error can result in the subtraction producing a negative // time. Guard against that. cpu_time_used_ += std::max(ReadCpuTimerOfChoice() - start_cpu_time_, 0); } // Called by each thread void SetIterationTime(double seconds) { manual_time_used_ += seconds; } bool running() const { return running_; } // REQUIRES: timer is not running double real_time_used() const { BM_CHECK(!running_); return real_time_used_; } // REQUIRES: timer is not running double cpu_time_used() const { BM_CHECK(!running_); return cpu_time_used_; } // REQUIRES: timer is not running double manual_time_used() const { BM_CHECK(!running_); return manual_time_used_; } private: double ReadCpuTimerOfChoice() const { if (measure_process_cpu_time) return ProcessCPUUsage(); return ThreadCPUUsage(); } // should the thread, or the process, time be measured? const bool measure_process_cpu_time; bool running_ = false; // Is the timer running double start_real_time_ = 0; // If running_ double start_cpu_time_ = 0; // If running_ // Accumulated time so far (does not contain current slice if running_) double real_time_used_ = 0; double cpu_time_used_ = 0; // Manually set iteration time. User sets this with SetIterationTime(seconds). double manual_time_used_ = 0; }; } // namespace internal } // namespace benchmark #endif // BENCHMARK_THREAD_TIMER_H