Kokkos_Threads.hpp

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//                        Kokkos v. 3.0
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//               Solutions of Sandia, LLC (NTESS).
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#ifndef KOKKOS_THREADS_HPP
#define KOKKOS_THREADS_HPP

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

#include <Kokkos_Core_fwd.hpp>

#include <cstddef>
#include <iosfwd>
#include <Kokkos_HostSpace.hpp>
#include <Kokkos_ScratchSpace.hpp>
#include <Kokkos_Layout.hpp>
#include <Kokkos_MemoryTraits.hpp>
#include <impl/Kokkos_Profiling_Interface.hpp>
#include <impl/Kokkos_Tags.hpp>

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

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

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

namespace Kokkos {

class Threads {
 public:

  typedef Threads execution_space;
  typedef Kokkos::HostSpace memory_space;

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

  typedef Kokkos::LayoutRight array_layout;
  typedef memory_space::size_type size_type;

  typedef ScratchMemorySpace<Threads> scratch_memory_space;

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


  static int in_parallel();

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

  static void impl_static_fence();

#ifdef KOKKOS_ENABLE_DEPRECATED_CODE
  static void fence();
#else
  void fence() const;
#endif

  static int concurrency();

#ifdef KOKKOS_ENABLE_DEPRECATED_CODE
  static bool sleep();

  static bool wake();

  static void finalize();

  static void initialize(unsigned threads_count             = 0,
                         unsigned use_numa_count            = 0,
                         unsigned use_cores_per_numa        = 0,
                         bool allow_asynchronous_threadpool = false);

  static int is_initialized();

  static Threads& instance(int = 0);

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

  static int thread_pool_size(int depth = 0);
#if defined(KOKKOS_ACTIVE_EXECUTION_MEMORY_SPACE_HOST)
  static int thread_pool_rank();
#else
  KOKKOS_INLINE_FUNCTION static int thread_pool_rank() { return 0; }
#endif

  inline static unsigned max_hardware_threads() { return thread_pool_size(0); }
  KOKKOS_INLINE_FUNCTION static unsigned hardware_thread_id() {
    return thread_pool_rank();
  }
#else
  static void impl_finalize();

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


  static void impl_initialize(unsigned threads_count             = 0,
                              unsigned use_numa_count            = 0,
                              unsigned use_cores_per_numa        = 0,
                              bool allow_asynchronous_threadpool = false);

  static int impl_is_initialized();

  static Threads& impl_instance(int = 0);

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

  static int impl_thread_pool_size(int depth = 0);
#if defined(KOKKOS_ACTIVE_EXECUTION_MEMORY_SPACE_HOST)
  static int impl_thread_pool_rank();
#else
  KOKKOS_INLINE_FUNCTION static int impl_thread_pool_rank() { return 0; }
#endif

  inline static unsigned impl_max_hardware_threads() {
    return impl_thread_pool_size(0);
  }
  KOKKOS_INLINE_FUNCTION static unsigned impl_hardware_thread_id() {
    return impl_thread_pool_rank();
  }
#endif

  uint32_t impl_instance_id() const noexcept { return 0; }

  static const char* name();
  //----------------------------------------
};

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

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

namespace Kokkos {
namespace Impl {

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

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

}  // namespace Impl
}  // namespace Kokkos

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

#include <Kokkos_ExecPolicy.hpp>
#include <Kokkos_Parallel.hpp>
#include <Threads/Kokkos_ThreadsExec.hpp>
#include <Threads/Kokkos_ThreadsTeam.hpp>
#include <Threads/Kokkos_Threads_Parallel.hpp>

#include <KokkosExp_MDRangePolicy.hpp>

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

#endif /* #if defined( KOKKOS_ENABLE_THREADS ) */
#endif /* #define KOKKOS_THREADS_HPP */