Kokkos_OpenMP.hpp

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#ifndef KOKKOS_OPENMP_HPP
#define KOKKOS_OPENMP_HPP

#include <Kokkos_Macros.hpp>
#if defined(KOKKOS_ENABLE_OPENMP)

#include <Kokkos_Core_fwd.hpp>

#include <cstddef>
#include <iosfwd>
#include <Kokkos_HostSpace.hpp>

#ifdef KOKKOS_ENABLE_HBWSPACE
#include <Kokkos_HBWSpace.hpp>
#endif

#include <Kokkos_ScratchSpace.hpp>
#include <Kokkos_Parallel.hpp>
#include <Kokkos_TaskScheduler.hpp>
#include <Kokkos_Layout.hpp>
#include <impl/Kokkos_Tags.hpp>

#include <vector>

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

namespace Kokkos {

namespace Impl {
class OpenMPExec;
}

class OpenMP {
 public:
  using execution_space = OpenMP;

  using memory_space =
#ifdef KOKKOS_ENABLE_HBWSPACE
      Experimental::HBWSpace;
#else
      HostSpace;
#endif

  using device_type          = Kokkos::Device<execution_space, memory_space>;
  using array_layout         = LayoutRight;
  using size_type            = memory_space::size_type;
  using scratch_memory_space = ScratchMemorySpace<OpenMP>;

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

  inline static bool in_parallel(OpenMP const& = OpenMP()) noexcept;

  static void impl_static_fence(OpenMP const& = OpenMP()) noexcept;

#ifdef KOKKOS_ENABLE_DEPRECATED_CODE
  static void fence(OpenMP const& = OpenMP()) noexcept;
#else
  void fence() const;
#endif

  inline static bool is_asynchronous(OpenMP const& = OpenMP()) noexcept;

  static std::vector<OpenMP> partition(...);

  static OpenMP create_instance(...);

  template <typename F>
  static void partition_master(F const& f, int requested_num_partitions = 0,
                               int requested_partition_size = 0);

  // use UniqueToken
  static int concurrency();

#ifdef KOKKOS_ENABLE_DEPRECATED_CODE
  static void initialize(int thread_count, int use_numa_count,
                         int use_cores_per_numa = 0);

  static void initialize(int thread_count = -1);

  static bool is_initialized() noexcept;

  static void finalize();

  inline static int thread_pool_size() noexcept;

  KOKKOS_INLINE_FUNCTION
  static int thread_pool_rank() noexcept;

  inline static int thread_pool_size(int depth);

  static void sleep(){};
  static void wake(){};

  // Using omp_get_max_threads(); is problematic
  // On Intel (essentially an initial call to the OpenMP runtime
  // without a parallel region before will set a process mask for a single core
  // The runtime will than bind threads for a parallel region to other cores on
  // the entering the first parallel region and make the process mask the
  // aggregate of the thread masks. The intend seems to be to make serial code
  // run fast, if you compile with OpenMP enabled but don't actually use
  // parallel regions or so static int omp_max_threads = omp_get_max_threads();
  static int get_current_max_threads() noexcept;

  // use UniqueToken
  inline static int max_hardware_threads() noexcept;

  // use UniqueToken
  KOKKOS_INLINE_FUNCTION
  static int hardware_thread_id() noexcept;
#else
  static void impl_initialize(int thread_count = -1);

  static bool impl_is_initialized() noexcept;

  static void impl_finalize();

  inline static int impl_thread_pool_size() noexcept;

  KOKKOS_INLINE_FUNCTION
  static int impl_thread_pool_rank() noexcept;

  inline static int impl_thread_pool_size(int depth);

  // use UniqueToken
  inline static int impl_max_hardware_threads() noexcept;

  // use UniqueToken
  KOKKOS_INLINE_FUNCTION
  static int impl_hardware_thread_id() noexcept;

  static int impl_get_current_max_threads() noexcept;
#endif

  static constexpr const char* name() noexcept { return "OpenMP"; }
  uint32_t impl_instance_id() const noexcept { return 0; }
};

namespace Profiling {
namespace Experimental {
template <>
struct DeviceTypeTraits<OpenMP> {
  static constexpr DeviceType id = DeviceType::OpenMP;
};
}  // namespace Experimental
}  // namespace Profiling
}  // namespace Kokkos

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

namespace Kokkos {
namespace Impl {

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

template <>
struct VerifyExecutionCanAccessMemorySpace<
    Kokkos::OpenMP::memory_space, Kokkos::OpenMP::scratch_memory_space> {
  enum { value = true };
  inline static void verify(void) {}
  inline static void verify(const void*) {}
};

}  // namespace Impl
}  // namespace Kokkos

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

#include <OpenMP/Kokkos_OpenMP_Exec.hpp>
#include <OpenMP/Kokkos_OpenMP_Team.hpp>
#include <OpenMP/Kokkos_OpenMP_Parallel.hpp>
#include <OpenMP/Kokkos_OpenMP_Task.hpp>

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

#endif /* #if defined( KOKKOS_ENABLE_OPENMP ) && defined( _OPENMP ) */
#endif /* #ifndef KOKKOS_OPENMP_HPP */