Line data    Source code

       1              : !!****m* ABINIT/m_ompgpu_utils
       2              : !! NAME
       3              : !!  m_ompgpu_utils
       4              : !!
       5              : !! FUNCTION
       6              : !!  Collection of routines useful for leveraging OpenMP GPU offload capabilities.
       7              : !!
       8              : !! COPYRIGHT
       9              : !!  Copyright (C) 2000-2026 ABINIT group (MT)
      10              : !!  This file is distributed under the terms of the
      11              : !!  GNU General Public License, see ~abinit/COPYING
      12              : !!  or http://www.gnu.org/copyleft/gpl.txt .
      13              : !!
      14              : !! SOURCE
      15              : 
      16              : #if defined HAVE_CONFIG_H
      17              : #include "config.h"
      18              : #endif
      19              : 
      20              : #include "abi_common.h"
      21              : 
      22              : module m_ompgpu_utils
      23              : 
      24              :  use defs_basis
      25              :  use m_errors
      26              :  use m_abicore
      27              :  use m_xmpi
      28              :  use, intrinsic :: iso_c_binding, only : c_loc, c_associated
      29              : 
      30              :  implicit none
      31              : 
      32              :  private
      33              : 
      34              : 
      35              : #ifdef HAVE_OPENMP_OFFLOAD
      36              :  ! pointer to GPU buffers
      37              :  integer, pointer, save :: cur_kg_k(:,:) => null()
      38              :  integer, pointer, save :: cur_kg_kp(:,:) => null()
      39              :  real(dp), pointer, save :: cur_ffnl_k(:,:,:,:) => null()
      40              :  real(dp), pointer, save :: cur_ph3d_k(:,:,:) => null()
      41              :  integer, pointer, save :: cur_kg_k_gather(:,:) => null()
      42              : #endif
      43              : 
      44              :  public :: ompgpu_load_hamilt_buffers
      45              :  public :: ompgpu_free_hamilt_buffers
      46              : 
      47              : contains
      48              : 
      49            0 :  subroutine ompgpu_load_hamilt_buffers(kg_k,kg_kp,ffnl_k,ph3d_k,kg_k_gather)
      50              :    integer,intent(in),target :: kg_k(:,:), kg_kp(:,:)
      51              :    real(dp),intent(in),target :: ffnl_k(:,:,:,:),ph3d_k(:,:,:)
      52              :    integer,intent(in),target,optional :: kg_k_gather(:,:)
      53              : 
      54              : #ifdef HAVE_OPENMP_OFFLOAD
      55              :    if(associated(cur_kg_k)) call ompgpu_free_hamilt_buffers()
      56              : 
      57              :    cur_kg_k            => kg_k
      58              :    cur_ffnl_k          => ffnl_k
      59              :    cur_ph3d_k          => ph3d_k
      60              :    !$OMP TARGET ENTER DATA MAP(to:kg_k,ffnl_k,ph3d_k)
      61              :    if (.not. c_associated(c_loc(kg_k), c_loc(kg_kp))) then
      62              :      cur_kg_kp           => kg_kp
      63              :      !$OMP TARGET ENTER DATA MAP(to:kg_kp)
      64              :    end if
      65              :    if(present(kg_k_gather)) then
      66              :      cur_kg_k_gather     => kg_k_gather
      67              :      !$OMP TARGET ENTER DATA MAP(to:kg_k_gather)
      68              :    end if
      69              : #else
      70              :    ABI_UNUSED((/kg_k,kg_kp,kg_k_gather/))
      71              :    ABI_UNUSED((/ffnl_k,ph3d_k/))
      72            0 :    ABI_BUG("ABINIT wasn't compiled with OpenMP GPU offloading, aborting.")
      73              : #endif
      74            0 :  end subroutine ompgpu_load_hamilt_buffers
      75              : 
      76            0 :  subroutine ompgpu_free_hamilt_buffers()
      77              : #ifdef HAVE_OPENMP_OFFLOAD
      78              : 
      79              :    !$OMP TARGET EXIT DATA MAP(release:cur_kg_k,cur_ffnl_k,cur_ph3d_k)
      80              :    cur_ffnl_k          => null()
      81              :    cur_ph3d_k          => null()
      82              :    cur_kg_k            => null()
      83              :    if(associated(cur_kg_kp)) then
      84              :      !$OMP TARGET EXIT DATA MAP(release:cur_kg_kp)
      85              :      cur_kg_kp           => null()
      86              :    end if
      87              :    if(associated(cur_kg_k_gather)) then
      88              :      !$OMP TARGET EXIT DATA MAP(release:cur_kg_k_gather)
      89              :      cur_kg_k_gather     => null()
      90              :    end if
      91              : #else
      92            0 :    ABI_BUG("ABINIT wasn't compiled with OpenMP GPU offloading, aborting.")
      93              : #endif
      94            0 :  end subroutine ompgpu_free_hamilt_buffers
      95              : 
      96              : end module m_ompgpu_utils
      97              : !!***