include/gmx_parallel_3dfft.h

   1 /* -*- mode: c; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; c-file-style: "stroustrup"; -*-
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  18
  19 #ifndef _gmx_parallel_3dfft_h_
  20 #define _gmx_parallel_3dfft_h_
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26
  27 #include "types/simple.h"
  28 #include "types/commrec.h"
  29 #include "gmxcomplex.h"
  30 #include "gmx_fft.h"
  31
  32 typedef struct gmx_parallel_3dfft *
  33 gmx_parallel_3dfft_t;
  34
  35
  36
  37 /*! \brief Initialize parallel MPI-based 3D-FFT.
  38  *
  39  *  This routine performs real-to-complex and complex-to-real parallel 3D FFTs,
  40  *  but not complex-to-complex.
  41  *
  42  *  The routine is optimized for small-to-medium size FFTs used for PME and
  43  *  PPPM algorithms, and do allocate extra workspace whenever it might improve
  44  *  performance.
  45  *
  46  *  \param pfft_setup     Pointer to parallel 3dfft setup structure, previously
  47  *                        allocated or with automatic storage.
  48  *  \param ngridx         Global number of grid cells in the x direction. Must be
  49  *                        divisible by the number of nodes.
  50  *  \param ngridy         Global number of grid cells in the y direction. Must be
  51  *                        divisible by the number of nodes.
  52  *  \param ngridz         Global number of grid cells in the z direction.
  53  *  \param node2slab      Node id to slab index array, can be NULL.
  54  *  \param slab2grid_x    Slab index to grid_x array (nnodes+1), can be NULL.
  55  *  \param comm           MPI communicator, must have been initialized.
  56  *  \param bReproducible  Try to avoid FFT timing optimizations and other stuff
  57  *                        that could make results differ for two runs with
  58  *                        identical input (reproducibility for debugging).
  59  *
  60  *  \return 0 or a standard error code.
  61  */
  62 int
  63 gmx_parallel_3dfft_init   (gmx_parallel_3dfft_t *    pfft_setup,
  64                            ivec                      ndata,
  65                                                    real **                   real_data,
  66                                                    t_complex **              complex_data,
  67                            MPI_Comm                  comm[2],
  68                            int *                     slab2index_major,
  69                            int *                     slab2index_minor,
  70                            bool                      bReproducible);
  71
  72
  73
  74
  75
  76 /*! \brief Get direct space grid index limits
  77  */
  78 int
  79 gmx_parallel_3dfft_real_limits(gmx_parallel_3dfft_t      pfft_setup,
  80                                                            ivec                      local_ndata,
  81                                                            ivec                      local_offset,
  82                                                            ivec                      local_size);
  83
  84
  85 /*! \brief Get reciprocal space grid index limits
  86  */
  87 int
  88 gmx_parallel_3dfft_complex_limits(gmx_parallel_3dfft_t      pfft_setup,
  89                                   ivec                      complex_order,
  90                                                                   ivec                      local_ndata,
  91                                                                   ivec                      local_offset,
  92                                                                   ivec                      local_size);
  93
  94
  95 int
  96 gmx_parallel_3dfft_execute(gmx_parallel_3dfft_t    pfft_setup,
  97                                                    enum gmx_fft_direction  dir,
  98                                                    void *                  in_data,
  99                                                    void *                  out_data);
 100
 101
 102 /*! \brief Release all data in parallel fft setup
 103  *
 104  *  All temporary storage and FFT plans are released. The structure itself
 105  *  is not released, but the contents is invalid after this call.
 106  *
 107  *  \param pfft_setup Parallel 3dfft setup.
 108  *
 109  *  \return 0 or a standard error code.
 110  */
 111 int
 112 gmx_parallel_3dfft_destroy(gmx_parallel_3dfft_t    pfft_setup);
 113
 114
 115
 116
 117 #endif /* _gmx_parallel_3dfft_h_ */
 118