vtk-m2/vtkm/cont/Timer.h
Kenneth Moreland 85265a9c84 Add const correctness to Timer
It should be possible to query a vtkm::cont::Timer without modifying it.
As such, its query functions (such as Stopped and GetElapsedTime) should
be const.
2019-02-28 15:08:16 -07:00

106 lines
3.6 KiB
C++

//============================================================================
// Copyright (c) Kitware, Inc.
// All rights reserved.
// See LICENSE.txt for details.
// This software is distributed WITHOUT ANY WARRANTY; without even
// the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
// PURPOSE. See the above copyright notice for more information.
//
// Copyright 2014 National Technology & Engineering Solutions of Sandia, LLC (NTESS).
// Copyright 2014 UT-Battelle, LLC.
// Copyright 2014 Los Alamos National Security.
//
// Under the terms of Contract DE-NA0003525 with NTESS,
// the U.S. Government retains certain rights in this software.
//
// Under the terms of Contract DE-AC52-06NA25396 with Los Alamos National
// Laboratory (LANL), the U.S. Government retains certain rights in
// this software.
//============================================================================
#ifndef vtk_m_cont_Timer_h
#define vtk_m_cont_Timer_h
#include <vtkm/ListTag.h>
#include <vtkm/cont/DeviceAdapter.h>
#include <vtkm/cont/DeviceAdapterListTag.h>
#include <vtkm/cont/vtkm_cont_export.h>
#include <memory>
namespace vtkm
{
namespace cont
{
namespace detail
{
class EnabledDeviceTimerImpls;
}
/// A class that can be used to time operations in VTK-m that might be occuring
/// in parallel. Users are recommended to provide a device adapter at construction
/// time which matches the one being used to execute algorithms to ensure that thread
/// synchronization is correct and accurate.
/// If no device adapter is provided at construction time, the maximum
/// elapsed time of all enabled deivces will be returned. Normally cuda is expected to
/// have the longest execution time if enabled.
/// Per device adapter time query is also supported. It's useful when users want to reuse
/// the same timer to measure the cuda kernal call as well as the cuda device execution.
/// It is also possible to change the device adapter after construction by calling the form
/// of the Reset method with a new DeviceAdapterId.
///
/// The there is no guaranteed resolution of the time but should generally be
/// good to about a millisecond.
///
class VTKM_CONT_EXPORT Timer
{
public:
VTKM_CONT
Timer();
VTKM_CONT Timer(vtkm::cont::DeviceAdapterId device);
VTKM_CONT ~Timer();
/// Resets the timer.
VTKM_CONT void Reset();
/// Resets the timer and changes the device to time on.
VTKM_CONT void Reset(vtkm::cont::DeviceAdapterId device);
/// Start would call Reset function before starting the timer for convenience
VTKM_CONT void Start();
VTKM_CONT void Stop();
VTKM_CONT bool Started() const;
VTKM_CONT bool Stopped() const;
/// Used to check if Timer has finished the synchronization to get the result from the device.
VTKM_CONT bool Ready() const;
/// Get the elapsed time measured by the given device adapter. If no device is
/// specified, the max time of all device measurements will be returned.
VTKM_CONT
vtkm::Float64 GetElapsedTime(
vtkm::cont::DeviceAdapterId id = vtkm::cont::DeviceAdapterTagAny()) const;
/// Returns the device for which this timer is synchronized. If the device adapter has the same
/// id as DeviceAdapterTagAny, then the timer will synchronize all devices.
VTKM_CONT vtkm::cont::DeviceAdapterId GetDevice() const { return this->Device; }
private:
VTKM_CONT void Init();
/// Some timers are ill-defined when copied, so disallow that for all timers.
VTKM_CONT Timer(const Timer&) = delete;
VTKM_CONT void operator=(const Timer&) = delete;
DeviceAdapterId Device;
std::unique_ptr<detail::EnabledDeviceTimerImpls> Internal;
};
}
} // namespace vtkm::cont
#endif //vtk_m_cont_Timer_h