Kokkos_Cuda.hpp

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//                        Kokkos v. 2.0
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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 <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>


/*--------------------------------------------------------------------------*/

namespace Kokkos {
namespace Impl {
class CudaExec ;
} // namespace Impl
} // namespace Kokkos

/*--------------------------------------------------------------------------*/

namespace Kokkos {

class Cuda {
public:


  typedef Cuda                  execution_space ;

#if defined( KOKKOS_ENABLE_CUDA_UVM )
  typedef CudaUVMSpace          memory_space ;
#else
  typedef CudaSpace             memory_space ;
#endif

  typedef Kokkos::Device<execution_space,memory_space> device_type;

  typedef memory_space::size_type  size_type ;

  typedef LayoutLeft            array_layout ;

  typedef ScratchMemorySpace< Cuda >  scratch_memory_space ;

  //--------------------------------------------------


  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 fence();

  static void finalize();

  static int is_initialized();

  static int concurrency();

  static void print_configuration( std::ostream & , const bool detail = false );

  //--------------------------------------------------

  ~Cuda() {}
  Cuda();
  explicit Cuda( const int instance_id );

  Cuda( Cuda && ) = default ;
  Cuda( const Cuda & ) = default ;
  Cuda & operator = ( Cuda && ) = default ;
  Cuda & operator = ( const Cuda & ) = default ;

  //--------------------------------------------------------------------------


  struct SelectDevice {
    int cuda_device_id ;
    SelectDevice() : cuda_device_id(0) {}
    explicit SelectDevice( int id ) : cuda_device_id( id ) {}
  };

  static void 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 { return m_stream ; }
  int          cuda_device() const { return m_device ; }

  //--------------------------------------------------------------------------

  static const char* name();

private:

  cudaStream_t m_stream ;
  int          m_device ;
};

} // namespace Kokkos

/*--------------------------------------------------------------------------*/
/*--------------------------------------------------------------------------*/

namespace Kokkos {
namespace Impl {

template<>
struct MemorySpaceAccess
  < Kokkos::CudaSpace
  , Kokkos::Cuda::scratch_memory_space
  >
{
  enum { assignable = false };
  enum { accessible = true };
  enum { 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 { assignable = false };
  enum { accessible = true };
  enum { deepcopy   = false };
};

#endif


template<>
struct VerifyExecutionCanAccessMemorySpace
  < Kokkos::CudaSpace
  , Kokkos::Cuda::scratch_memory_space
  >
{
  enum { value = true };
  KOKKOS_INLINE_FUNCTION static void verify( void ) { }
  KOKKOS_INLINE_FUNCTION static void verify( const void * ) { }
};

template<>
struct VerifyExecutionCanAccessMemorySpace
  < Kokkos::HostSpace
  , Kokkos::Cuda::scratch_memory_space
  >
{
  enum { value = false };
  inline static void verify( void ) { CudaSpace::access_error(); }
  inline static void verify( const void * p ) { CudaSpace::access_error(p); }
};

} // namespace Impl
} // namespace Kokkos

/*--------------------------------------------------------------------------*/
/*--------------------------------------------------------------------------*/

#include <Cuda/Kokkos_CudaExec.hpp>
#include <Cuda/Kokkos_Cuda_View.hpp>
#include <Cuda/Kokkos_Cuda_Team.hpp>
#include <Cuda/Kokkos_Cuda_Parallel.hpp>
#include <Cuda/Kokkos_Cuda_Task.hpp>

#include <KokkosExp_MDRangePolicy.hpp>
//----------------------------------------------------------------------------

#endif /* #if defined( KOKKOS_ENABLE_CUDA ) */
#endif /* #ifndef KOKKOS_CUDA_HPP */