include/split.h

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  38
  39 #ifndef _split_h
  40 #define _split_h
  41
  42 /*
  43  * Determine on which node a particle should reside and on which
  44  * node is also should be available. The distribution algorithm
  45  * should account for the actual ring architecture and how nodes
  46  * are numbered. The typedef t_splitd has two separate structures that
  47  * describe the distribution:
  48  *
  49  * The nodeinfo part describes which node containst which particles,
  50  * while the nodeids part describes on which node(s) a particle can be
  51  * found and what local particle number is assigned to it.
  52  *
  53  */
  54
  55 #include <stdio.h>
  56 #include "typedefs.h"
  57
  58 #ifdef __cplusplus
  59 extern "C" {
  60 #endif
  61
  62 typedef enum {
  63     SPLIT_NONE, SPLIT_SORTX, SPLIT_REDUCE, SPLIT_NR
  64 } t_splitalg;
  65
  66 typedef struct
  67 {
  68     int      hid;
  69     atom_id *nodeid;
  70 } t_nodeids;
  71
  72 typedef struct
  73 {
  74     int  nr;    /* Length of the long list.                         */
  75     int *lst;   /* The actual list.                                 */
  76 } t_nlist;
  77
  78 typedef struct
  79 {
  80     t_nlist home;   /* List of home particles.                          */
  81 } t_nodeinfo;
  82
  83 typedef struct
  84 {
  85     int         nnodes;   /* Number of nodes this splitinfo is for.      */
  86     t_nodeinfo *nodeinfo; /* Home and available particles for each node. */
  87     int         nnodeids; /* Number of particles this splitinfo is for.       */
  88     t_nodeids  *nodeids;  /* List of node id's for every particle,       */
  89     /* entry[nodeid] gives the local atom id (NO_ATID if*/
  90     /* not available). Entry[MAXNODES] contains home    */
  91     /* node's id.                                  */
  92 } t_splitd;
  93
  94 void init_splitd(t_splitd *splitd, int nnodes, int nnodeids);
  95 /*
  96  * Initialises the splitd data structure for the specified number of
  97  * nodes (nnodes) and number of atoms (nnodeids).
  98  */
  99
 100 void make_splitd(t_splitalg algorithm, int nnodes, t_topology *top,
 101                  rvec *x, t_splitd *splitd, char *loadfile);
 102 /*
 103  * Initialises the splitd data structure for the specified number of
 104  * nodes (nnodes) and number of atoms (top) and fills it using
 105  * the specified algorithm (algorithm):
 106  *
 107  *    SPLIT_NONE   : Generate partial systems by dividing it into nnodes
 108  *                   consecutive, equal, parts without any intelligence.
 109  *    SPLIT_SORTX  : Like SPLIT_NONE but sort the coordinates before
 110  *                   dividing the system into nnodes consecutive, equal,
 111  *                   parts.
 112  *    SPLIT_REDUCE : Like SPLIT_NONE but minimise the bond lengths, i.e
 113  *                   invoke the reduce algorithm before dividing the
 114  *                   system into nnodes consecutive, equal, parts.
 115  *
 116  * The topology (top) and the coordinates (x) are not modified. The
 117  * calculations of bonded forces are assigned to the node with
 118  * the highest id that has one of the needed particles as home particle.
 119  */
 120
 121 long wr_split(FILE *fp, t_splitd *splitd);
 122 /*
 123  * Writes the split descriptor (splitd) to the file specified by fp.
 124  */
 125
 126 long rd_split(FILE *fp, t_splitd *splitd);
 127 /*
 128  * Reads the split descriptor (splitd) from the file specified by fp.
 129  */
 130
 131 void rm_splitd(t_splitd *splitd);
 132 /*
 133  * Frees all allocated space for the splitd data structure.
 134  */
 135
 136 void pr_splitd(FILE *fp, int indent, char *title, t_splitd *splitd);
 137 /*
 138  * This routine prints out a (human) readable representation of
 139  * the split descriptor to the file fp. Ident specifies the
 140  * number of spaces the text should be indented. Title is used
 141  * to print a header text.
 142  */
 143
 144 void split_topology(t_splitalg algorithm, int nnodes, t_topology *top,
 145                     rvec x[], char *loadfile);
 146 /*
 147  * Distributes the non-bonded forces defined in top over nnodes nodes
 148  * using the algoritm specified by algorithm. The distribution is made
 149  * by creating a split descriptor and then putting a bonded force on the
 150  * highest home node number of the paricles involved.
 151  */
 152
 153 #ifdef __cplusplus
 154 }
 155 #endif
 156
 157 #endif  /* _split_h */