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lammps/lib/gpu/atomic_gpu_memory.h
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atomic_gpu_memory.h
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/* ----------------------------------------------------------------------
LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
http://lammps.sandia.gov, Sandia National Laboratories
Steve Plimpton, sjplimp@sandia.gov
Copyright (2003) Sandia Corporation. Under the terms of Contract
DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
certain rights in this software. This software is distributed under
the GNU General Public License.
See the README file in the top-level LAMMPS directory.
------------------------------------------------------------------------- */
/* ----------------------------------------------------------------------
Contributing authors: Mike Brown (ORNL), brownw@ornl.gov
------------------------------------------------------------------------- */
#ifndef ATOMIC_GPU_MEMORY_H
#define ATOMIC_GPU_MEMORY_H
#include "pair_gpu_device.h"
#include "pair_gpu_balance.h"
#include "mpi.h"
#ifdef USE_OPENCL
#include "geryon/ocl_texture.h"
#else
#include "geryon/nvd_texture.h"
#endif
template <class numtyp, class acctyp>
class AtomicGPUMemory {
public:
AtomicGPUMemory();
virtual ~AtomicGPUMemory();
/// Clear any previous data and set up for a new LAMMPS run
/** \param max_nbors initial number of rows in the neighbor matrix
* \param cell_size cutoff + skin
* \param gpu_split fraction of particles handled by device
*
* Returns:
* - 0 if successfull
* - -1 if fix gpu not found
* - -3 if there is an out of memory error
* - -4 if the GPU library was not compiled for GPU
* - -5 Double precision is not supported on card **/
int init_atomic(const int nlocal, const int nall, const int max_nbors,
const int maxspecial, const double cell_size,
const double gpu_split, FILE *screen,
const char *pair_program);
/// Estimate the overhead for GPU context changes and CPU driver
void estimate_gpu_overhead();
/// Check if there is enough storage for atom arrays and realloc if not
/** \param success set to false if insufficient memory **/
inline void resize_atom(const int inum, const int nall, bool &success) {
if (atom->resize(nall, success))
pos_tex.bind_float(atom->dev_x,4);
ans->resize(inum,success);
}
/// Check if there is enough storage for neighbors and realloc if not
/** \param nlocal number of particles whose nbors must be stored on device
* \param host_inum number of particles whose nbors need to copied to host
* \param current maximum number of neighbors
* \note olist_size=total number of local particles **/
inline void resize_local(const int inum, const int max_nbors, bool &success) {
nbor->resize(inum,max_nbors,success);
}
/// Check if there is enough storage for neighbors and realloc if not
/** \param nlocal number of particles whose nbors must be stored on device
* \param host_inum number of particles whose nbors need to copied to host
* \param current maximum number of neighbors
* \note host_inum is 0 if the host is performing neighboring
* \note nlocal+host_inum=total number local particles
* \note olist_size=0 **/
inline void resize_local(const int inum, const int host_inum,
const int max_nbors, bool &success) {
nbor->resize(inum,host_inum,max_nbors,success);
}
/// Clear all host and device data
/** \note This is called at the beginning of the init() routine **/
void clear_atomic();
/// Returns memory usage on device per atom
int bytes_per_atom_atomic(const int max_nbors) const;
/// Total host memory used by library for pair style
double host_memory_usage_atomic() const;
/// Accumulate timers
inline void acc_timers() {
if (device->time_device()) {
if (nbor_time_avail) {
nbor->time_nbor.add_to_total();
nbor->time_kernel.add_to_total();
nbor_time_avail=false;
}
time_pair.add_to_total();
atom->acc_timers();
ans->acc_timers();
}
}
/// Zero timers
inline void zero_timers() {
nbor_time_avail=false;
time_pair.zero();
atom->zero_timers();
ans->zero_timers();
}
/// Copy neighbor list from host
int * reset_nbors(const int nall, const int inum, int *ilist, int *numj,
int **firstneigh, bool &success);
/// Build neighbor list on device
void build_nbor_list(const int inum, const int host_inum,
const int nall, double **host_x, int *host_type,
double *sublo, double *subhi, int *tag, int **nspecial,
int **special, bool &success);
/// Pair loop with host neighboring
void compute(const int f_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);
/// Pair loop with device neighboring
int * compute(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,
const double cpu_time, bool &success);
/// Pair loop with device neighboring
int ** compute(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 **numj, const double cpu_time, bool &success);
// -------------------------- DEVICE DATA -------------------------
/// Device Properties and Atom and Neighbor storage
PairGPUDevice<numtyp,acctyp> *device;
/// Geryon device
UCL_Device *ucl_device;
/// Device Timers
UCL_Timer time_pair;
/// Host device load balancer
PairGPUBalance<numtyp,acctyp> hd_balancer;
/// LAMMPS pointer for screen output
FILE *screen;
// --------------------------- ATOM DATA --------------------------
/// Atom Data
PairGPUAtom<numtyp,acctyp> *atom;
// ------------------------ FORCE/ENERGY DATA -----------------------
PairGPUAns<numtyp,acctyp> *ans;
// --------------------------- NBOR DATA ----------------------------
/// Neighbor data
PairGPUNbor *nbor;
/// True if we need to accumulate time for neighboring
bool nbor_time_avail;
// ------------------------- DEVICE KERNELS -------------------------
UCL_Program *pair_program;
UCL_Kernel k_pair_fast, k_pair;
inline int block_size() { return _block_size; }
// --------------------------- TEXTURES -----------------------------
UCL_Texture pos_tex;
protected:
bool _compiled;
int _block_size, _threads_per_atom;
double _max_bytes, _max_an_bytes;
double _gpu_overhead, _driver_overhead;
UCL_D_Vec<int> *_nbor_data;
void compile_kernels(UCL_Device &dev, const char *pair_string);
virtual void loop(const bool _eflag, const bool _vflag) = 0;
};
#endif
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