Kokkos_Cuda.hpp

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#ifndef KOKKOS_CUDA_HPP
#define KOKKOS_CUDA_HPP
 
#include <Kokkos_Macros.hpp>
#if defined(KOKKOS_ENABLE_CUDA)
 
#include <Kokkos_Core_fwd.hpp>
 
#include <iosfwd>
#include <vector>
 
#include <impl/Kokkos_AnalyzePolicy.hpp>
#include <Kokkos_CudaSpace.hpp>
 
#include <Kokkos_Parallel.hpp>
#include <Kokkos_TaskScheduler.hpp>
#include <Kokkos_Layout.hpp>
#include <Kokkos_ScratchSpace.hpp>
#include <Kokkos_MemoryTraits.hpp>
#include <impl/Kokkos_Tags.hpp>
#include <impl/Kokkos_ExecSpaceInitializer.hpp>
#include <impl/Kokkos_HostSharedPtr.hpp>
 
/*--------------------------------------------------------------------------*/
 
namespace Kokkos {
namespace Impl {
class CudaExec;
class CudaInternal;
}  // namespace Impl
}  // namespace Kokkos
 
/*--------------------------------------------------------------------------*/
 
namespace Kokkos {
 
namespace Impl {
namespace Experimental {
enum class CudaLaunchMechanism : unsigned {
  Default        = 0,
  ConstantMemory = 1,
  GlobalMemory   = 2,
  LocalMemory    = 4
};
 
constexpr inline CudaLaunchMechanism operator|(CudaLaunchMechanism p1,
                                               CudaLaunchMechanism p2) {
  return static_cast<CudaLaunchMechanism>(static_cast<unsigned>(p1) |
                                          static_cast<unsigned>(p2));
}
constexpr inline CudaLaunchMechanism operator&(CudaLaunchMechanism p1,
                                               CudaLaunchMechanism p2) {
  return static_cast<CudaLaunchMechanism>(static_cast<unsigned>(p1) &
                                          static_cast<unsigned>(p2));
}
 
template <CudaLaunchMechanism l>
struct CudaDispatchProperties {
  CudaLaunchMechanism launch_mechanism = l;
};
}  // namespace Experimental
}  // namespace Impl
class Cuda {
 public:
 
 
  using execution_space = Cuda;
 
#if defined(KOKKOS_ENABLE_CUDA_UVM)
  using memory_space = CudaUVMSpace;
#else
  using memory_space = CudaSpace;
#endif
 
  using device_type = Kokkos::Device<execution_space, memory_space>;
 
  using size_type = memory_space::size_type;
 
  using array_layout = LayoutLeft;
 
  using scratch_memory_space = ScratchMemorySpace<Cuda>;
 
  //--------------------------------------------------
 
 
  KOKKOS_INLINE_FUNCTION static int in_parallel() {
#if defined(__CUDA_ARCH__)
    return true;
#else
    return false;
#endif
  }
 
  static bool sleep();
 
  static bool wake();
 
  static void impl_static_fence();
 
  void fence() const;
 
  static int concurrency();
 
  static void print_configuration(std::ostream&, const bool detail = false);
 
  //--------------------------------------------------
 
  Cuda();
 
  Cuda(cudaStream_t stream);
 
  //--------------------------------------------------------------------------
 
 
  struct SelectDevice {
    int cuda_device_id;
    SelectDevice() : cuda_device_id(0) {}
    explicit SelectDevice(int id) : cuda_device_id(id) {}
  };
 
  static void impl_finalize();
 
  static int impl_is_initialized();
 
  static void impl_initialize(const SelectDevice         = SelectDevice(),
                              const size_t num_instances = 1);
 
  static size_type device_arch();
 
  static size_type detect_device_count();
 
  static std::vector<unsigned> detect_device_arch();
 
  cudaStream_t cuda_stream() const;
  int cuda_device() const;
  const cudaDeviceProp& cuda_device_prop() const;
 
  //--------------------------------------------------------------------------
 
  static const char* name();
 
  inline Impl::CudaInternal* impl_internal_space_instance() const {
    return m_space_instance.get();
  }
  uint32_t impl_instance_id() const noexcept { return 0; }
 
 private:
  Kokkos::Impl::HostSharedPtr<Impl::CudaInternal> m_space_instance;
};
 
namespace Tools {
namespace Experimental {
template <>
struct DeviceTypeTraits<Cuda> {
  static constexpr DeviceType id = DeviceType::Cuda;
};
}  // namespace Experimental
}  // namespace Tools
 
namespace Impl {
 
class CudaSpaceInitializer : public ExecSpaceInitializerBase {
 public:
  CudaSpaceInitializer()  = default;
  ~CudaSpaceInitializer() = default;
  void initialize(const InitArguments& args) final;
  void finalize(const bool all_spaces) final;
  void fence() final;
  void print_configuration(std::ostream& msg, const bool detail) final;
};
 
}  // namespace Impl
}  // namespace Kokkos
 
/*--------------------------------------------------------------------------*/
/*--------------------------------------------------------------------------*/
 
namespace Kokkos {
namespace Impl {
 
template <>
struct MemorySpaceAccess<Kokkos::CudaSpace,
                         Kokkos::Cuda::scratch_memory_space> {
  enum : bool { assignable = false };
  enum : bool { accessible = true };
  enum : bool { deepcopy = false };
};
 
#if defined(KOKKOS_ENABLE_CUDA_UVM)
 
// If forcing use of UVM everywhere
// then must assume that CudaUVMSpace
// can be a stand-in for CudaSpace.
// This will fail when a strange host-side execution space
// that defines CudaUVMSpace as its preferredmemory space.
 
template <>
struct MemorySpaceAccess<Kokkos::CudaUVMSpace,
                         Kokkos::Cuda::scratch_memory_space> {
  enum : bool { assignable = false };
  enum : bool { accessible = true };
  enum : bool { deepcopy = false };
};
 
#endif
 
}  // namespace Impl
}  // namespace Kokkos
 
#endif /* #if defined( KOKKOS_ENABLE_CUDA ) */
#endif /* #ifndef KOKKOS_CUDA_HPP */