git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@7281 f3b2605a-c512-4ea7-a41b-209d697bcdaa

lib/gpu/lal_answer.h

@@ -0,0 +1,169 @@
+/***************************************************************************
+                                  answer.h
+                             -------------------
+                            W. Michael Brown (ORNL)
+
+  Class for data management of forces, torques, energies, and virials
+
+ __________________________________________________________________________
+    This file is part of the LAMMPS Accelerator Library (LAMMPS_AL)
+ __________________________________________________________________________
+
+    begin                : 
+    email                : brownw@ornl.gov
+ ***************************************************************************/
+
+#ifndef LAL_ANSWER_H
+#define LAL_ANSWER_H
+
+#include <math.h>
+#include "mpi.h"
+
+#ifdef USE_OPENCL
+
+#include "geryon/ocl_timer.h"
+#include "geryon/ocl_mat.h"
+using namespace ucl_opencl;
+
+#else
+
+#include "geryon/nvd_timer.h"
+#include "geryon/nvd_mat.h"
+using namespace ucl_cudadr;
+
+#endif
+
+#include "lal_precision.h"
+
+namespace LAMMPS_AL {
+
+template <class numtyp, class acctyp>
+class Answer {
+ public:
+  Answer();
+  ~Answer() { clear(); }
+
+  /// Current number of local atoms stored
+  inline int inum() const { return _inum; }
+  /// Set number of local atoms for future copy operations
+  inline void inum(const int n) { _inum=n; }
+  
+  /// Memory usage per atom in this class
+  int bytes_per_atom() const; 
+
+  /// Clear any previous data and set up for a new LAMMPS run
+  /** \param rot True if atom storage needs quaternions **/
+  bool init(const int inum, const bool charge, const bool rot, UCL_Device &dev);
+  
+  /// Check if we have enough device storage and realloc if not
+  inline void resize(const int inum, bool &success) {
+    _inum=inum;
+    if (inum>_max_local) {
+      clear_resize();
+      success = success && alloc(inum);
+    }
+  }
+  
+  /// If already initialized by another LAMMPS style, add fields as necessary
+  /** \param rot True if atom storage needs quaternions **/
+  bool add_fields(const bool charge, const bool rot);
+  
+  /// Free all memory on host and device needed to realloc for more atoms
+  void clear_resize();
+
+  /// Free all memory on host and device
+  void clear();
+ 
+  /// Return the total amount of host memory used by class in bytes
+  double host_memory_usage() const;
+
+  /// Add copy times to timers
+  inline void acc_timers() {
+    time_answer.add_to_total();
+  }
+
+  /// Add copy times to timers
+  inline void zero_timers() {
+    time_answer.zero();
+  }
+
+  /// Return the total time for host/device data transfer
+  inline double transfer_time() {
+    return time_answer.total_seconds();
+  }
+  
+  /// Return the total time for data cast/pack
+  inline double cast_time() { return _time_cast; }
+  
+  /// Return number of bytes used on device
+  inline double gpu_bytes() { return _gpu_bytes; } 
+
+  // -------------------------COPY FROM GPU -------------------------------
+
+  /// Copy answers from device into read buffer asynchronously
+  void copy_answers(const bool eflag, const bool vflag,
+                    const bool ef_atom, const bool vf_atom);
+
+  /// Copy answers from device into read buffer asynchronously
+  void copy_answers(const bool eflag, const bool vflag,
+                    const bool ef_atom, const bool vf_atom, int *ilist);
+  
+  /// Copy energy and virial data into LAMMPS memory
+  double energy_virial(double *eatom, double **vatom, double *virial);
+
+  /// Copy energy and virial data into LAMMPS memory
+  double energy_virial(double *eatom, double **vatom, double *virial,
+                       double &ecoul);
+
+  /// Add forces and torques from the GPU into a LAMMPS pointer
+  void get_answers(double **f, double **tor);
+
+  inline double get_answers(double **f, double **tor, double *eatom, 
+                            double **vatom, double *virial, double &ecoul) {
+    double ta=MPI_Wtime();
+    time_answer.sync_stop();
+    _time_cpu_idle+=MPI_Wtime()-ta;
+    double ts=MPI_Wtime();
+    double evdw=energy_virial(eatom,vatom,virial,ecoul);
+    get_answers(f,tor);
+    _time_cast+=MPI_Wtime()-ts;
+    return evdw;
+  }
+  
+  /// Return the time the CPU was idle waiting for GPU
+  inline double cpu_idle_time() { return _time_cpu_idle; }
+
+  // ------------------------------ DATA ----------------------------------
+
+  /// Force and possibly torque
+  UCL_D_Vec<acctyp> dev_ans;
+  /// Energy and virial per-atom storage
+  UCL_D_Vec<acctyp> dev_engv;
+  
+  /// Force and possibly torque data on host
+  UCL_H_Vec<acctyp> host_ans;
+  /// Energy/virial data on host
+  UCL_H_Vec<acctyp> host_engv;
+  
+  /// Device timers
+  UCL_Timer time_answer;
+  
+  /// Geryon device
+  UCL_Device *dev;
+
+ private:
+  bool alloc(const int inum);
+  
+  bool _allocated, _eflag, _vflag, _ef_atom, _vf_atom, _rot, _charge, _other;
+  int _max_local, _inum, _e_fields, _ev_fields;
+  int *_ilist;
+  double _time_cast, _time_cpu_idle;
+  
+  double _gpu_bytes;
+  
+  bool _newton;
+};
+
+}
+
+#endif