1 /***************************************************************************
2                                  lj96_ext.cpp
3                              -------------------
4                             W. Michael Brown (ORNL)
5 
6   Functions for LAMMPS access to lj96/cut acceleration routines.
7 
8  __________________________________________________________________________
9     This file is part of the LAMMPS Accelerator Library (LAMMPS_AL)
10  __________________________________________________________________________
11 
12     begin                :
13     email                : brownw@ornl.gov
14  ***************************************************************************/
15 
16 #include <iostream>
17 #include <cassert>
18 #include <math.h>
19 
20 #include "lal_lj96.h"
21 
22 using namespace std;
23 using namespace LAMMPS_AL;
24 
25 static LJ96<PRECISION,ACC_PRECISION> LJ96MF;
26 
27 // ---------------------------------------------------------------------------
28 // Allocate memory on host and device and copy constants to device
29 // ---------------------------------------------------------------------------
lj96_gpu_init(const int ntypes,double ** cutsq,double ** host_lj1,double ** host_lj2,double ** host_lj3,double ** host_lj4,double ** offset,double * special_lj,const int inum,const int nall,const int max_nbors,const int maxspecial,const double cell_size,int & gpu_mode,FILE * screen)30 int lj96_gpu_init(const int ntypes, double **cutsq, double **host_lj1,
31                   double **host_lj2, double **host_lj3, double **host_lj4,
32                   double **offset, double *special_lj, const int inum,
33                   const int nall, const int max_nbors, const int maxspecial,
34                   const double cell_size, int &gpu_mode, FILE *screen) {
35   LJ96MF.clear();
36   gpu_mode=LJ96MF.device->gpu_mode();
37   double gpu_split=LJ96MF.device->particle_split();
38   int first_gpu=LJ96MF.device->first_device();
39   int last_gpu=LJ96MF.device->last_device();
40   int world_me=LJ96MF.device->world_me();
41   int gpu_rank=LJ96MF.device->gpu_rank();
42   int procs_per_gpu=LJ96MF.device->procs_per_gpu();
43 
44   LJ96MF.device->init_message(screen,"lj96/cut",first_gpu,last_gpu);
45 
46   bool message=false;
47   if (LJ96MF.device->replica_me()==0 && screen)
48     message=true;
49 
50   if (message) {
51     fprintf(screen,"Initializing GPU and compiling on process 0...");
52     fflush(screen);
53   }
54 
55   int init_ok=0;
56   if (world_me==0)
57     init_ok=LJ96MF.init(ntypes, cutsq, host_lj1, host_lj2, host_lj3,
58                         host_lj4, offset, special_lj, inum, nall, 300,
59                         maxspecial, cell_size, gpu_split, screen);
60 
61   LJ96MF.device->world_barrier();
62   if (message)
63     fprintf(screen,"Done.\n");
64 
65   for (int i=0; i<procs_per_gpu; i++) {
66     if (message) {
67       if (last_gpu-first_gpu==0)
68         fprintf(screen,"Initializing GPU %d on core %d...",first_gpu,i);
69       else
70         fprintf(screen,"Initializing GPUs %d-%d on core %d...",first_gpu,
71                 last_gpu,i);
72       fflush(screen);
73     }
74     if (gpu_rank==i && world_me!=0)
75       init_ok=LJ96MF.init(ntypes, cutsq, host_lj1, host_lj2, host_lj3, host_lj4,
76                           offset, special_lj, inum,  nall, 300, maxspecial,
77                           cell_size, gpu_split, screen);
78 
79     LJ96MF.device->gpu_barrier();
80     if (message)
81       fprintf(screen,"Done.\n");
82   }
83   if (message)
84     fprintf(screen,"\n");
85 
86   if (init_ok==0)
87     LJ96MF.estimate_gpu_overhead();
88   return init_ok;
89 }
90 
lj96_gpu_clear()91 void lj96_gpu_clear() {
92   LJ96MF.clear();
93 }
94 
lj96_gpu_compute_n(const int ago,const int inum_full,const int nall,double ** host_x,int * host_type,double * sublo,double * subhi,int * tag,int ** nspecial,int ** special,const bool eflag,const bool vflag,const bool eatom,const bool vatom,int & host_start,int ** ilist,int ** jnum,const double cpu_time,bool & success)95 int** lj96_gpu_compute_n(const int ago, const int inum_full,
96                          const int nall, double **host_x, int *host_type,
97                          double *sublo, double *subhi, int *tag, int **nspecial,
98                          int **special, const bool eflag, const bool vflag,
99                          const bool eatom, const bool vatom, int &host_start,
100                          int **ilist, int **jnum, const double cpu_time,
101                          bool &success) {
102   return LJ96MF.compute(ago, inum_full, nall, host_x, host_type, sublo,
103                         subhi, tag, nspecial, special, eflag, vflag, eatom,
104                         vatom, host_start, ilist, jnum, cpu_time, success);
105 }
106 
lj96_gpu_compute(const int ago,const int inum_full,const int nall,double ** host_x,int * host_type,int * ilist,int * numj,int ** firstneigh,const bool eflag,const bool vflag,const bool eatom,const bool vatom,int & host_start,const double cpu_time,bool & success)107 void lj96_gpu_compute(const int ago, const int inum_full, const int nall,
108                       double **host_x, int *host_type, int *ilist, int *numj,
109                       int **firstneigh, const bool eflag, const bool vflag,
110                       const bool eatom, const bool vatom, int &host_start,
111                       const double cpu_time, bool &success) {
112   LJ96MF.compute(ago,inum_full,nall,host_x,host_type,ilist,numj,firstneigh,
113                  eflag,vflag,eatom,vatom,host_start,cpu_time,success);
114 }
115 
lj96_gpu_bytes()116 double lj96_gpu_bytes() {
117   return LJ96MF.host_memory_usage();
118 }
119 
120 
121