thread_timer.h (1716B)
1 #ifndef BENCHMARK_THREAD_TIMER_H 2 #define BENCHMARK_THREAD_TIMER_H 3 4 #include "check.h" 5 #include "timers.h" 6 7 namespace benchmark { 8 namespace internal { 9 10 class ThreadTimer { 11 public: 12 ThreadTimer() = default; 13 14 // Called by each thread 15 void StartTimer() { 16 running_ = true; 17 start_real_time_ = ChronoClockNow(); 18 start_cpu_time_ = ThreadCPUUsage(); 19 } 20 21 // Called by each thread 22 void StopTimer() { 23 CHECK(running_); 24 running_ = false; 25 real_time_used_ += ChronoClockNow() - start_real_time_; 26 // Floating point error can result in the subtraction producing a negative 27 // time. Guard against that. 28 cpu_time_used_ += std::max<double>(ThreadCPUUsage() - start_cpu_time_, 0); 29 } 30 31 // Called by each thread 32 void SetIterationTime(double seconds) { manual_time_used_ += seconds; } 33 34 bool running() const { return running_; } 35 36 // REQUIRES: timer is not running 37 double real_time_used() { 38 CHECK(!running_); 39 return real_time_used_; 40 } 41 42 // REQUIRES: timer is not running 43 double cpu_time_used() { 44 CHECK(!running_); 45 return cpu_time_used_; 46 } 47 48 // REQUIRES: timer is not running 49 double manual_time_used() { 50 CHECK(!running_); 51 return manual_time_used_; 52 } 53 54 private: 55 bool running_ = false; // Is the timer running 56 double start_real_time_ = 0; // If running_ 57 double start_cpu_time_ = 0; // If running_ 58 59 // Accumulated time so far (does not contain current slice if running_) 60 double real_time_used_ = 0; 61 double cpu_time_used_ = 0; 62 // Manually set iteration time. User sets this with SetIterationTime(seconds). 63 double manual_time_used_ = 0; 64 }; 65 66 } // namespace internal 67 } // namespace benchmark 68 69 #endif // BENCHMARK_THREAD_TIMER_H