text: /* Copyright (c) 2020, NVIDIA CORPORATION. All rights reserved.
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   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *  * Neither the name of NVIDIA CORPORATION nor the names of its
   *    contributors may be used to endorse or promote products derived
   *    from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
   * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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   */
  
  #pragma once
  #ifndef __PISIM_H__
  #define __PISIM_H__
  
  #include <vector>
  #include <cuda_runtime_api.h>
  #include <curand.h>
  #include <curand_kernel.h>
  #include <cuda.h>
  
  #include "helper_multiprocess.h"
  
  typedef float vec2[2];
  
  class MonteCarloPiSimulation {
    size_t m_numPoints;
  
    // Pointers to Cuda allocated buffers which are imported and used by vulkan as
    // vertex buffer
    vec2 *m_xyVector;
    float *m_pointsInsideCircle;
  
    // Pointers to device and host allocated memories storing number of points
    // that are inside the unit circle
    float *m_numPointsInCircle;
    float *m_hostNumPointsInCircle;
  
    int m_blocks, m_threads;
  
    // Total size of allocations created by cuMemMap Apis. This size is the sum of
    // sizes of m_xyVector and m_pointsInsideCircle buffers.
    size_t m_totalAllocationSize;
  
    // Shareable Handles(a file descriptor on Linux and NT Handle on Windows),
    // used for sharing cuda
    // allocated memory with Vulkan
    ShareableHandle m_posShareableHandle, m_inCircleShareableHandle;
  
    // Cuda Device corresponding to the Vulkan Physical device
    int m_cudaDevice;
  
    // Track and accumulate total points that have been simulated since start of
    // the sample. The idea is to get a closer approximation to PI with time.
    size_t m_totalPointsInsideCircle;
    size_t m_totalPointsSimulated;
  
    void setupSimulationAllocations();
    void cleanupSimulationAllocations();
    void getIdealExecutionConfiguration();
  
   public:
    MonteCarloPiSimulation(size_t num_points);
    ~MonteCarloPiSimulation();
    void initSimulation(int cudaDevice, cudaStream_t stream = 0);
    void stepSimulation(float time, cudaStream_t stream = 0);
    static void computePiCallback(void *args);
  
    size_t getNumPoints() const { return m_numPoints; }
  
    float getNumPointsInCircle() const { return *m_hostNumPointsInCircle; }
  
    ShareableHandle &getPositionShareableHandle() { return m_posShareableHandle; }
    ShareableHandle &getInCircleShareableHandle() {
      return m_inCircleShareableHandle;
    }
  };
  
  #endif  // __PISIM_H__
  