src/gromacs/fft/parallel_3dfft.h

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  36
  37 #ifndef GMX_FFT_PARALLEL_3DFFT_H
  38 #define GMX_FFT_PARALLEL_3DFFT_H
  39
  40 #include "gromacs/fft/fft.h"
  41 #include "gromacs/gpu_utils/hostallocator.h"
  42 #include "gromacs/math/gmxcomplex.h"
  43 #include "gromacs/timing/wallcycle.h"
  44 #include "gromacs/utility/basedefinitions.h"
  45 #include "gromacs/utility/gmxmpi.h"
  46 #include "gromacs/utility/real.h"
  47
  48 typedef struct gmx_parallel_3dfft* gmx_parallel_3dfft_t;
  49
  50
  51 /*! \brief Initialize parallel MPI-based 3D-FFT.
  52  *
  53  *  This routine performs real-to-complex and complex-to-real parallel 3D FFTs,
  54  *  but not complex-to-complex.
  55  *
  56  *  The routine is optimized for small-to-medium size FFTs used for PME and
  57  *  PPPM algorithms, and do allocate extra workspace whenever it might improve
  58  *  performance.
  59  *
  60  *  \param pfft_setup     Pointer to parallel 3dfft setup structure, previously
  61  *                        allocated or with automatic storage.
  62  *  \param ndata          Number of grid cells in each direction
  63  *  \param real_data      Real data. Input for forward and output for backward.
  64  *  \param complex_data   Complex data.
  65  *  \param comm           MPI communicator for both parallelization axis.
  66  *                        Needs to be either initialized or MPI_NULL for
  67  *                        no parallelization in that axis.
  68  *  \param bReproducible  Try to avoid FFT timing optimizations and other stuff
  69  *                        that could make results differ for two runs with
  70  *                        identical input (reproducibility for debugging).
  71  *  \param nthreads       Run in parallel using n threads
  72  *  \param realGridAllocation  Whether to make real grid use allocation pinned for GPU transfers.
  73  *                             Only used in PME mixed CPU+GPU mode.
  74  *
  75  *  \return 0 or a standard error code.
  76  */
  77 int gmx_parallel_3dfft_init(gmx_parallel_3dfft_t* pfft_setup,
  78                             const ivec            ndata,
  79                             real**                real_data,
  80                             t_complex**           complex_data,
  81                             MPI_Comm              comm[2],
  82                             gmx_bool              bReproducible,
  83                             int                   nthreads,
  84                             gmx::PinningPolicy realGridAllocation = gmx::PinningPolicy::CannotBePinned);
  85
  86
  87 /*! \brief Get direct space grid index limits
  88  */
  89 int gmx_parallel_3dfft_real_limits(gmx_parallel_3dfft_t pfft_setup,
  90                                    ivec                 local_ndata,
  91                                    ivec                 local_offset,
  92                                    ivec                 local_size);
  93
  94
  95 /*! \brief Get reciprocal space grid index limits
  96  */
  97 int gmx_parallel_3dfft_complex_limits(gmx_parallel_3dfft_t pfft_setup,
  98                                       ivec                 complex_order,
  99                                       ivec                 local_ndata,
 100                                       ivec                 local_offset,
 101                                       ivec                 local_size);
 102
 103
 104 int gmx_parallel_3dfft_execute(gmx_parallel_3dfft_t   pfft_setup,
 105                                enum gmx_fft_direction dir,
 106                                int                    thread,
 107                                gmx_wallcycle_t        wcycle);
 108
 109
 110 /*! \brief Release all data in parallel fft setup
 111  *
 112  *  All temporary storage and FFT plans are released. The structure itself
 113  *  is not released, but the contents is invalid after this call.
 114  *
 115  *  \param pfft_setup Parallel 3dfft setup.
 116  *
 117  *  \return 0 or a standard error code.
 118  */
 119 int gmx_parallel_3dfft_destroy(gmx_parallel_3dfft_t pfft_setup);
 120
 121 #endif