include/pme.h

   1 /*
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  35
  36 #ifndef _pme_h
  37 #define _pme_h
  38
  39 #ifdef HAVE_CONFIG_H
  40 #include <config.h>
  41 #endif
  42
  43 #include <stdio.h>
  44 #include "typedefs.h"
  45 #include "gmxcomplex.h"
  46 #include "fftgrid.h"
  47 #include "gmx_wallcycle.h"
  48
  49 typedef real *splinevec[DIM];
  50
  51 enum { GMX_SUM_QGRID_FORWARD, GMX_SUM_QGRID_BACKWARD };
  52
  53 extern int pme_inconvenient_nnodes(int nkx,int nky,int nnodes);
  54 /* Checks for FFT + solve_pme load imbalance, returns:
  55  * 0 when no or negligible load imbalance is expected
  56  * 1 when a slight load imbalance is expected
  57  * 2 when using less PME nodes is expected to be faster
  58  */
  59
  60 extern int gmx_pme_init(gmx_pme_t *pmedata,t_commrec *cr,int nnodes_major,
  61                         t_inputrec *ir,int homenr,
  62                         bool bFreeEnergy, bool bReproducible);
  63
  64 extern int gmx_pme_destroy(FILE *log,gmx_pme_t *pmedata);
  65 /* Initialize and destroy the pme data structures resepectively.
  66  * Return value 0 indicates all well, non zero is an error code.
  67  */
  68
  69 #define GMX_PME_SPREAD_Q      (1<<0)
  70 #define GMX_PME_SOLVE         (1<<1)
  71 #define GMX_PME_CALC_F        (1<<2)
  72 #define GMX_PME_DO_ALL  (GMX_PME_SPREAD_Q | GMX_PME_SOLVE | GMX_PME_CALC_F)
  73
  74 extern int gmx_pme_do(gmx_pme_t pme,
  75                       int start,       int homenr,
  76                       rvec x[],        rvec f[],
  77                       real chargeA[],  real chargeB[],
  78                       matrix box,      t_commrec *cr,
  79                       int  maxshift0,  int maxshift1,
  80                       t_nrnb *nrnb,
  81                       matrix lrvir,    real ewaldcoeff,
  82                       real *energy,    real lambda,
  83                       real *dvdlambda, int flags);
  84 /* Do a PME calculation for the long range electrostatics.
  85  * flags, defined above, determine which parts of the calculation are performed.
  86  * Return value 0 indicates all well, non zero is an error code.
  87  */
  88
  89 extern int gmx_pmeonly(gmx_pme_t pme,
  90                        t_commrec *cr,     t_nrnb *mynrnb,
  91                        gmx_wallcycle_t wcycle,
  92                        real ewaldcoeff,   bool bGatherOnly,
  93                        t_inputrec *ir);
  94 /* Called on the nodes that do PME exclusively (as slaves)
  95  */
  96
  97 extern void gmx_sum_qgrid(gmx_pme_t pme,t_commrec *cr,t_fftgrid *grid,
  98                           int direction);
  99
 100 extern void gmx_pme_calc_energy(gmx_pme_t pme,int n,rvec *x,real *q,real *V);
 101 /* Calculate the PME grid energy V for n charges with a potential
 102  * in the pme struct determined before with a call to gmx_pme_do
 103  * with at least GMX_PME_SPREAD_Q and GMX_PME_SOLVE specified.
 104  * Note that the charges are not spread on the grid in the pme struct.
 105  * Currently does not work in parallel or with free energy.
 106  */
 107
 108 /* The following three routines are for PME/PP node splitting in pme_pp.c */
 109
 110 /* Abstract type for PME <-> PP communication */
 111 typedef struct gmx_pme_pp *gmx_pme_pp_t;
 112
 113 extern gmx_pme_pp_t gmx_pme_pp_init(t_commrec *cr);
 114 /* Initialize the PME-only side of the PME <-> PP communication */
 115
 116 extern void gmx_pme_send_q(t_commrec *cr,
 117                            bool bFreeEnergy, real *chargeA, real *chargeB,
 118                            int maxshift0, int maxshift1);
 119 /* Send the charges and maxshift to out PME-only node. */
 120
 121 extern void gmx_pme_send_x(t_commrec *cr, matrix box, rvec *x,
 122                            bool bFreeEnergy, real lambda, gmx_large_int_t step);
 123 /* Send the coordinates to our PME-only node and request a PME calculation */
 124
 125 extern void gmx_pme_finish(t_commrec *cr);
 126 /* Tell our PME-only node to finish */
 127
 128 extern void gmx_pme_receive_f(t_commrec *cr,
 129                               rvec f[], matrix vir,
 130                               real *energy, real *dvdlambda,
 131                               float *pme_cycles);
 132 /* PP nodes receive the long range forces from the PME nodes */
 133
 134 extern int gmx_pme_recv_q_x(gmx_pme_pp_t pme_pp,
 135                             real **chargeA, real **chargeB,
 136                             matrix box, rvec **x,rvec **f,
 137                             int *maxshift0,int *maxshift1,
 138                             bool *bFreeEnergy,real *lambda,
 139                             gmx_large_int_t *step);
 140 /* Receive charges and/or coordinates from the PP-only nodes.
 141  * Returns the number of atoms, or -1 when the run is finished.
 142  */
 143
 144 extern void gmx_pme_send_force_vir_ener(gmx_pme_pp_t pme_pp,
 145                                         rvec *f, matrix vir,
 146                                         real energy, real dvdlambda,
 147                                         float cycles,
 148                                         bool bGotTermSignal,
 149                                         bool bGotUsr1Signal);
 150 /* Send the PME mesh force, virial and energy to the PP-only nodes */
 151
 152 #endif