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 #ifdef __cplusplus
  50 extern "C" {
  51 #endif
  52
  53 typedef real *splinevec[DIM];
  54
  55 enum { GMX_SUM_QGRID_FORWARD, GMX_SUM_QGRID_BACKWARD };
  56
  57 extern int pme_inconvenient_nnodes(int nkx,int nky,int nnodes);
  58 /* Checks for FFT + solve_pme load imbalance, returns:
  59  * 0 when no or negligible load imbalance is expected
  60  * 1 when a slight load imbalance is expected
  61  * 2 when using less PME nodes is expected to be faster
  62  */
  63
  64 extern int gmx_pme_init(gmx_pme_t *pmedata,t_commrec *cr,int nnodes_major,
  65                         t_inputrec *ir,int homenr,
  66                         bool bFreeEnergy, bool bReproducible);
  67
  68 extern int gmx_pme_destroy(FILE *log,gmx_pme_t *pmedata);
  69 /* Initialize and destroy the pme data structures resepectively.
  70  * Return value 0 indicates all well, non zero is an error code.
  71  */
  72
  73 #define GMX_PME_SPREAD_Q      (1<<0)
  74 #define GMX_PME_SOLVE         (1<<1)
  75 #define GMX_PME_CALC_F        (1<<2)
  76 #define GMX_PME_DO_ALL  (GMX_PME_SPREAD_Q | GMX_PME_SOLVE | GMX_PME_CALC_F)
  77
  78 extern int gmx_pme_do(gmx_pme_t pme,
  79                       int start,       int homenr,
  80                       rvec x[],        rvec f[],
  81                       real chargeA[],  real chargeB[],
  82                       matrix box,      t_commrec *cr,
  83                       int  maxshift0,  int maxshift1,
  84                       t_nrnb *nrnb,    gmx_wallcycle_t wcycle,
  85                       matrix lrvir,    real ewaldcoeff,
  86                       real *energy,    real lambda,
  87                       real *dvdlambda, int flags);
  88 /* Do a PME calculation for the long range electrostatics.
  89  * flags, defined above, determine which parts of the calculation are performed.
  90  * Return value 0 indicates all well, non zero is an error code.
  91  */
  92
  93 extern int gmx_pmeonly(gmx_pme_t pme,
  94                        t_commrec *cr,     t_nrnb *mynrnb,
  95                        gmx_wallcycle_t wcycle,
  96                        real ewaldcoeff,   bool bGatherOnly,
  97                        t_inputrec *ir);
  98 /* Called on the nodes that do PME exclusively (as slaves)
  99  */
 100
 101 extern void gmx_sum_qgrid(gmx_pme_t pme,t_commrec *cr,t_fftgrid *grid,
 102                           int direction);
 103
 104 extern void gmx_pme_calc_energy(gmx_pme_t pme,int n,rvec *x,real *q,real *V);
 105 /* Calculate the PME grid energy V for n charges with a potential
 106  * in the pme struct determined before with a call to gmx_pme_do
 107  * with at least GMX_PME_SPREAD_Q and GMX_PME_SOLVE specified.
 108  * Note that the charges are not spread on the grid in the pme struct.
 109  * Currently does not work in parallel or with free energy.
 110  */
 111
 112 /* The following three routines are for PME/PP node splitting in pme_pp.c */
 113
 114 /* Abstract type for PME <-> PP communication */
 115 typedef struct gmx_pme_pp *gmx_pme_pp_t;
 116
 117 extern gmx_pme_pp_t gmx_pme_pp_init(t_commrec *cr);
 118 /* Initialize the PME-only side of the PME <-> PP communication */
 119
 120 extern void gmx_pme_send_q(t_commrec *cr,
 121                            bool bFreeEnergy, real *chargeA, real *chargeB,
 122                            int maxshift0, int maxshift1);
 123 /* Send the charges and maxshift to out PME-only node. */
 124
 125 extern void gmx_pme_send_x(t_commrec *cr, matrix box, rvec *x,
 126                            bool bFreeEnergy, real lambda, gmx_large_int_t step);
 127 /* Send the coordinates to our PME-only node and request a PME calculation */
 128
 129 extern void gmx_pme_finish(t_commrec *cr);
 130 /* Tell our PME-only node to finish */
 131
 132 extern void gmx_pme_receive_f(t_commrec *cr,
 133                               rvec f[], matrix vir,
 134                               real *energy, real *dvdlambda,
 135                               float *pme_cycles);
 136 /* PP nodes receive the long range forces from the PME nodes */
 137
 138 extern int gmx_pme_recv_q_x(gmx_pme_pp_t pme_pp,
 139                             real **chargeA, real **chargeB,
 140                             matrix box, rvec **x,rvec **f,
 141                             int *maxshift0,int *maxshift1,
 142                             bool *bFreeEnergy,real *lambda,
 143                             gmx_large_int_t *step);
 144 /* Receive charges and/or coordinates from the PP-only nodes.
 145  * Returns the number of atoms, or -1 when the run is finished.
 146  */
 147
 148 extern void gmx_pme_send_force_vir_ener(gmx_pme_pp_t pme_pp,
 149                                         rvec *f, matrix vir,
 150                                         real energy, real dvdlambda,
 151                                         float cycles,
 152                                         bool bGotStopNextStepSignal,
 153                                         bool bGotStopNextNbrStepSignal);
 154 /* Send the PME mesh force, virial and energy to the PP-only nodes */
 155
 156 #ifdef __cplusplus
 157 }
 158 #endif
 159
 160 #endif