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45 #include "types/simple.h"
46 #include "types/nbnxn_pairlist.h"
47 #include "types/nb_verlet.h"
48 #include "types/ishift.h"
49 #include "types/force_flags.h"
50 #include "../nbnxn_consts.h"
53 #include "thread_mpi/atomic.h"
56 #include "nbnxn_cuda_types.h"
57 #include "../../gmxlib/cuda_tools/cudautils.cuh"
58 #include "nbnxn_cuda.h"
59 #include "nbnxn_cuda_data_mgmt.h"
61 #if defined TEXOBJ_SUPPORTED && __CUDA_ARCH__ >= 300
65 /*! Texture reference for LJ C6/C12 parameters; bound to cu_nbparam_t.nbfp */
66 texture<float, 1, cudaReadModeElementType> nbfp_texref;
68 /*! Texture reference for LJ-PME parameters; bound to cu_nbparam_t.nbfp_comb */
69 texture<float, 1, cudaReadModeElementType> nbfp_comb_texref;
71 /*! Texture reference for Ewald coulomb force table; bound to cu_nbparam_t.coulomb_tab */
72 texture<float, 1, cudaReadModeElementType> coulomb_tab_texref;
74 /* Convenience defines */
75 #define NCL_PER_SUPERCL (NBNXN_GPU_NCLUSTER_PER_SUPERCLUSTER)
76 #define CL_SIZE (NBNXN_GPU_CLUSTER_SIZE)
78 /***** The kernels come here *****/
79 #include "nbnxn_cuda_kernel_utils.cuh"
81 /* Top-level kernel generation: will generate through multiple inclusion the
82 * following flavors for all kernels:
83 * - force-only output;
84 * - force and energy output;
85 * - force-only with pair list pruning;
86 * - force and energy output with pair list pruning.
89 #include "nbnxn_cuda_kernels.cuh"
90 /** Force & energy **/
92 #include "nbnxn_cuda_kernels.cuh"
95 /*** Pair-list pruning kernels ***/
98 #include "nbnxn_cuda_kernels.cuh"
99 /** Force & energy **/
100 #define CALC_ENERGIES
101 #include "nbnxn_cuda_kernels.cuh"
105 /*! Nonbonded kernel function pointer type */
106 typedef void (*nbnxn_cu_kfunc_ptr_t)(const cu_atomdata_t,
111 /*********************************/
113 /* XXX always/never run the energy/pruning kernels -- only for benchmarking purposes */
114 static bool always_ener = (getenv("GMX_GPU_ALWAYS_ENER") != NULL);
115 static bool never_ener = (getenv("GMX_GPU_NEVER_ENER") != NULL);
116 static bool always_prune = (getenv("GMX_GPU_ALWAYS_PRUNE") != NULL);
119 /* Bit-pattern used for polling-based GPU synchronization. It is used as a float
120 * and corresponds to having the exponent set to the maximum (127 -- single
121 * precision) and the mantissa to 0.
123 static unsigned int poll_wait_pattern = (0x7FU << 23);
125 /*! Returns the number of blocks to be used for the nonbonded GPU kernel. */
126 static inline int calc_nb_kernel_nblock(int nwork_units, cuda_dev_info_t *dinfo)
132 max_grid_x_size = dinfo->prop.maxGridSize[0];
134 /* do we exceed the grid x dimension limit? */
135 if (nwork_units > max_grid_x_size)
137 gmx_fatal(FARGS, "Watch out, the input system is too large to simulate!\n"
138 "The number of nonbonded work units (=number of super-clusters) exceeds the"
139 "maximum grid size in x dimension (%d > %d)!", nwork_units, max_grid_x_size);
146 /* Constant arrays listing all kernel function pointers and enabling selection
147 of a kernel in an elegant manner. */
149 /*! Pointers to the non-bonded kernels organized in 2-dim arrays by:
150 * electrostatics and VDW type.
152 * Note that the row- and column-order of function pointers has to match the
153 * order of corresponding enumerated electrostatics and vdw types, resp.,
154 * defined in nbnxn_cuda_types.h.
157 /*! Force-only kernel function pointers. */
158 static const nbnxn_cu_kfunc_ptr_t nb_kfunc_noener_noprune_ptr[eelCuNR][evdwCuNR] =
160 { nbnxn_kernel_ElecCut_VdwLJ_F_cuda, nbnxn_kernel_ElecCut_VdwLJFsw_F_cuda, nbnxn_kernel_ElecCut_VdwLJPsw_F_cuda, nbnxn_kernel_ElecCut_VdwLJEwCombGeom_F_cuda, nbnxn_kernel_ElecCut_VdwLJEwCombLB_F_cuda },
161 { nbnxn_kernel_ElecRF_VdwLJ_F_cuda, nbnxn_kernel_ElecRF_VdwLJFsw_F_cuda, nbnxn_kernel_ElecRF_VdwLJPsw_F_cuda, nbnxn_kernel_ElecRF_VdwLJEwCombGeom_F_cuda, nbnxn_kernel_ElecRF_VdwLJEwCombLB_F_cuda },
162 { nbnxn_kernel_ElecEwQSTab_VdwLJ_F_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJFsw_F_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJPsw_F_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJEwCombGeom_F_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJEwCombLB_F_cuda },
163 { nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJ_F_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJFsw_F_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJPsw_F_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJEwCombGeom_F_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJEwCombLB_F_cuda },
164 { nbnxn_kernel_ElecEw_VdwLJ_F_cuda, nbnxn_kernel_ElecEw_VdwLJFsw_F_cuda, nbnxn_kernel_ElecEw_VdwLJPsw_F_cuda, nbnxn_kernel_ElecEw_VdwLJEwCombGeom_F_cuda, nbnxn_kernel_ElecEw_VdwLJEwCombLB_F_cuda },
165 { nbnxn_kernel_ElecEwTwinCut_VdwLJ_F_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJFsw_F_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJPsw_F_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJEwCombGeom_F_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJEwCombLB_F_cuda }
168 /*! Force + energy kernel function pointers. */
169 static const nbnxn_cu_kfunc_ptr_t nb_kfunc_ener_noprune_ptr[eelCuNR][evdwCuNR] =
171 { nbnxn_kernel_ElecCut_VdwLJ_VF_cuda, nbnxn_kernel_ElecCut_VdwLJFsw_VF_cuda, nbnxn_kernel_ElecCut_VdwLJPsw_VF_cuda, nbnxn_kernel_ElecCut_VdwLJEwCombGeom_VF_cuda, nbnxn_kernel_ElecCut_VdwLJEwCombLB_VF_cuda },
172 { nbnxn_kernel_ElecRF_VdwLJ_VF_cuda, nbnxn_kernel_ElecRF_VdwLJFsw_VF_cuda, nbnxn_kernel_ElecRF_VdwLJPsw_VF_cuda, nbnxn_kernel_ElecRF_VdwLJEwCombGeom_VF_cuda, nbnxn_kernel_ElecRF_VdwLJEwCombLB_VF_cuda },
173 { nbnxn_kernel_ElecEwQSTab_VdwLJ_VF_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJFsw_VF_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJPsw_VF_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJEwCombGeom_VF_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJEwCombLB_VF_cuda },
174 { nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJ_VF_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJFsw_VF_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJPsw_VF_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJEwCombGeom_VF_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJEwCombLB_VF_cuda },
175 { nbnxn_kernel_ElecEw_VdwLJ_VF_cuda, nbnxn_kernel_ElecEw_VdwLJFsw_VF_cuda, nbnxn_kernel_ElecEw_VdwLJPsw_VF_cuda, nbnxn_kernel_ElecEw_VdwLJEwCombGeom_VF_cuda, nbnxn_kernel_ElecEw_VdwLJEwCombLB_VF_cuda },
176 { nbnxn_kernel_ElecEwTwinCut_VdwLJ_VF_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJFsw_VF_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJPsw_VF_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJEwCombGeom_VF_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJEwCombLB_VF_cuda }
179 /*! Force + pruning kernel function pointers. */
180 static const nbnxn_cu_kfunc_ptr_t nb_kfunc_noener_prune_ptr[eelCuNR][evdwCuNR] =
182 { nbnxn_kernel_ElecCut_VdwLJ_F_prune_cuda, nbnxn_kernel_ElecCut_VdwLJFsw_F_prune_cuda, nbnxn_kernel_ElecCut_VdwLJPsw_F_prune_cuda, nbnxn_kernel_ElecCut_VdwLJEwCombGeom_F_prune_cuda, nbnxn_kernel_ElecCut_VdwLJEwCombLB_F_prune_cuda },
183 { nbnxn_kernel_ElecRF_VdwLJ_F_prune_cuda, nbnxn_kernel_ElecRF_VdwLJFsw_F_prune_cuda, nbnxn_kernel_ElecRF_VdwLJPsw_F_prune_cuda, nbnxn_kernel_ElecRF_VdwLJEwCombGeom_F_prune_cuda, nbnxn_kernel_ElecRF_VdwLJEwCombLB_F_prune_cuda },
184 { nbnxn_kernel_ElecEwQSTab_VdwLJ_F_prune_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJFsw_F_prune_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJPsw_F_prune_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJEwCombGeom_F_prune_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJEwCombLB_F_prune_cuda },
185 { nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJ_F_prune_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJFsw_F_prune_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJPsw_F_prune_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJEwCombGeom_F_prune_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJEwCombLB_F_prune_cuda },
186 { nbnxn_kernel_ElecEw_VdwLJ_F_prune_cuda, nbnxn_kernel_ElecEw_VdwLJFsw_F_prune_cuda, nbnxn_kernel_ElecEw_VdwLJPsw_F_prune_cuda, nbnxn_kernel_ElecEw_VdwLJEwCombGeom_F_prune_cuda, nbnxn_kernel_ElecEw_VdwLJEwCombLB_F_prune_cuda },
187 { nbnxn_kernel_ElecEwTwinCut_VdwLJ_F_prune_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJFsw_F_prune_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJPsw_F_prune_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJEwCombGeom_F_prune_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJEwCombLB_F_prune_cuda }
190 /*! Force + energy + pruning kernel function pointers. */
191 static const nbnxn_cu_kfunc_ptr_t nb_kfunc_ener_prune_ptr[eelCuNR][evdwCuNR] =
193 { nbnxn_kernel_ElecCut_VdwLJ_VF_prune_cuda, nbnxn_kernel_ElecCut_VdwLJFsw_VF_prune_cuda, nbnxn_kernel_ElecCut_VdwLJPsw_VF_prune_cuda, nbnxn_kernel_ElecCut_VdwLJEwCombGeom_VF_prune_cuda, nbnxn_kernel_ElecCut_VdwLJEwCombLB_VF_prune_cuda },
194 { nbnxn_kernel_ElecRF_VdwLJ_VF_prune_cuda, nbnxn_kernel_ElecRF_VdwLJFsw_VF_prune_cuda, nbnxn_kernel_ElecRF_VdwLJPsw_VF_prune_cuda, nbnxn_kernel_ElecRF_VdwLJEwCombGeom_VF_prune_cuda, nbnxn_kernel_ElecRF_VdwLJEwCombLB_VF_prune_cuda },
195 { nbnxn_kernel_ElecEwQSTab_VdwLJ_VF_prune_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJFsw_VF_prune_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJPsw_VF_prune_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJEwCombGeom_VF_prune_cuda, nbnxn_kernel_ElecEwQSTab_VdwLJEwCombLB_VF_prune_cuda },
196 { nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJ_VF_prune_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJFsw_VF_prune_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJPsw_VF_prune_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJEwCombGeom_VF_prune_cuda, nbnxn_kernel_ElecEwQSTabTwinCut_VdwLJEwCombLB_VF_prune_cuda },
197 { nbnxn_kernel_ElecEw_VdwLJ_VF_prune_cuda, nbnxn_kernel_ElecEw_VdwLJFsw_VF_prune_cuda, nbnxn_kernel_ElecEw_VdwLJPsw_VF_prune_cuda, nbnxn_kernel_ElecEw_VdwLJEwCombGeom_VF_prune_cuda, nbnxn_kernel_ElecEw_VdwLJEwCombLB_VF_prune_cuda },
198 { nbnxn_kernel_ElecEwTwinCut_VdwLJ_VF_prune_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJFsw_VF_prune_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJPsw_VF_prune_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJEwCombGeom_VF_prune_cuda, nbnxn_kernel_ElecEwTwinCut_VdwLJEwCombLB_VF_prune_cuda }
201 /*! Return a pointer to the kernel version to be executed at the current step. */
202 static inline nbnxn_cu_kfunc_ptr_t select_nbnxn_kernel(int eeltype,
207 nbnxn_cu_kfunc_ptr_t res;
209 assert(eeltype < eelCuNR);
210 assert(evdwtype < eelCuNR);
216 res = nb_kfunc_ener_prune_ptr[eeltype][evdwtype];
220 res = nb_kfunc_ener_noprune_ptr[eeltype][evdwtype];
227 res = nb_kfunc_noener_prune_ptr[eeltype][evdwtype];
231 res = nb_kfunc_noener_noprune_ptr[eeltype][evdwtype];
238 /*! Calculates the amount of shared memory required by the CUDA kernel in use. */
239 static inline int calc_shmem_required()
243 /* size of shmem (force-buffers/xq/atom type preloading) */
244 /* NOTE: with the default kernel on sm3.0 we need shmem only for pre-loading */
245 /* i-atom x+q in shared memory */
246 shmem = NCL_PER_SUPERCL * CL_SIZE * sizeof(float4);
247 /* cj in shared memory, for both warps separately */
248 shmem += 2 * NBNXN_GPU_JGROUP_SIZE * sizeof(int);
250 /* i-atom types in shared memory */
251 shmem += NCL_PER_SUPERCL * CL_SIZE * sizeof(int);
253 #if __CUDA_ARCH__ < 300
254 /* force reduction buffers in shared memory */
255 shmem += CL_SIZE * CL_SIZE * 3 * sizeof(float);
261 /*! As we execute nonbonded workload in separate streams, before launching
262 the kernel we need to make sure that he following operations have completed:
263 - atomdata allocation and related H2D transfers (every nstlist step);
264 - pair list H2D transfer (every nstlist step);
265 - shift vector H2D transfer (every nstlist step);
266 - force (+shift force and energy) output clearing (every step).
268 These operations are issued in the local stream at the beginning of the step
269 and therefore always complete before the local kernel launch. The non-local
270 kernel is launched after the local on the same device/context, so this is
271 inherently scheduled after the operations in the local stream (including the
273 However, for the sake of having a future-proof implementation, we use the
274 misc_ops_done event to record the point in time when the above operations
275 are finished and synchronize with this event in the non-local stream.
277 void nbnxn_cuda_launch_kernel(nbnxn_cuda_ptr_t cu_nb,
278 const nbnxn_atomdata_t *nbatom,
283 int adat_begin, adat_len; /* local/nonlocal offset and length used for xq and f */
284 /* CUDA kernel launch-related stuff */
286 dim3 dim_block, dim_grid;
287 nbnxn_cu_kfunc_ptr_t nb_kernel = NULL; /* fn pointer to the nonbonded kernel */
289 cu_atomdata_t *adat = cu_nb->atdat;
290 cu_nbparam_t *nbp = cu_nb->nbparam;
291 cu_plist_t *plist = cu_nb->plist[iloc];
292 cu_timers_t *t = cu_nb->timers;
293 cudaStream_t stream = cu_nb->stream[iloc];
295 bool bCalcEner = flags & GMX_FORCE_VIRIAL;
296 bool bCalcFshift = flags & GMX_FORCE_VIRIAL;
297 bool bDoTime = cu_nb->bDoTime;
299 /* turn energy calculation always on/off (for debugging/testing only) */
300 bCalcEner = (bCalcEner || always_ener) && !never_ener;
302 /* don't launch the kernel if there is no work to do */
303 if (plist->nsci == 0)
308 /* calculate the atom data index range based on locality */
312 adat_len = adat->natoms_local;
316 adat_begin = adat->natoms_local;
317 adat_len = adat->natoms - adat->natoms_local;
320 /* When we get here all misc operations issues in the local stream are done,
321 so we record that in the local stream and wait for it in the nonlocal one. */
322 if (cu_nb->bUseTwoStreams)
324 if (iloc == eintLocal)
326 stat = cudaEventRecord(cu_nb->misc_ops_done, stream);
327 CU_RET_ERR(stat, "cudaEventRecord on misc_ops_done failed");
331 stat = cudaStreamWaitEvent(stream, cu_nb->misc_ops_done, 0);
332 CU_RET_ERR(stat, "cudaStreamWaitEvent on misc_ops_done failed");
336 /* beginning of timed HtoD section */
339 stat = cudaEventRecord(t->start_nb_h2d[iloc], stream);
340 CU_RET_ERR(stat, "cudaEventRecord failed");
344 cu_copy_H2D_async(adat->xq + adat_begin, nbatom->x + adat_begin * 4,
345 adat_len * sizeof(*adat->xq), stream);
349 stat = cudaEventRecord(t->stop_nb_h2d[iloc], stream);
350 CU_RET_ERR(stat, "cudaEventRecord failed");
353 /* beginning of timed nonbonded calculation section */
356 stat = cudaEventRecord(t->start_nb_k[iloc], stream);
357 CU_RET_ERR(stat, "cudaEventRecord failed");
360 /* get the pointer to the kernel flavor we need to use */
361 nb_kernel = select_nbnxn_kernel(nbp->eeltype,
364 plist->bDoPrune || always_prune);
366 /* kernel launch config */
367 nblock = calc_nb_kernel_nblock(plist->nsci, cu_nb->dev_info);
368 dim_block = dim3(CL_SIZE, CL_SIZE, 1);
369 dim_grid = dim3(nblock, 1, 1);
370 shmem = calc_shmem_required();
374 fprintf(debug, "GPU launch configuration:\n\tThread block: %dx%dx%d\n\t"
375 "Grid: %dx%d\n\t#Super-clusters/clusters: %d/%d (%d)\n",
376 dim_block.x, dim_block.y, dim_block.z,
377 dim_grid.x, dim_grid.y, plist->nsci*NCL_PER_SUPERCL,
378 NCL_PER_SUPERCL, plist->na_c);
381 nb_kernel<<< dim_grid, dim_block, shmem, stream>>> (*adat, *nbp, *plist, bCalcFshift);
382 CU_LAUNCH_ERR("k_calc_nb");
386 stat = cudaEventRecord(t->stop_nb_k[iloc], stream);
387 CU_RET_ERR(stat, "cudaEventRecord failed");
391 void nbnxn_cuda_launch_cpyback(nbnxn_cuda_ptr_t cu_nb,
392 const nbnxn_atomdata_t *nbatom,
397 int adat_begin, adat_len, adat_end; /* local/nonlocal offset and length used for xq and f */
400 /* determine interaction locality from atom locality */
405 else if (NONLOCAL_A(aloc))
412 sprintf(stmp, "Invalid atom locality passed (%d); valid here is only "
413 "local (%d) or nonlocal (%d)", aloc, eatLocal, eatNonlocal);
417 cu_atomdata_t *adat = cu_nb->atdat;
418 cu_timers_t *t = cu_nb->timers;
419 bool bDoTime = cu_nb->bDoTime;
420 cudaStream_t stream = cu_nb->stream[iloc];
422 bool bCalcEner = flags & GMX_FORCE_VIRIAL;
423 bool bCalcFshift = flags & GMX_FORCE_VIRIAL;
425 /* don't launch copy-back if there was no work to do */
426 if (cu_nb->plist[iloc]->nsci == 0)
431 /* calculate the atom data index range based on locality */
435 adat_len = adat->natoms_local;
436 adat_end = cu_nb->atdat->natoms_local;
440 adat_begin = adat->natoms_local;
441 adat_len = adat->natoms - adat->natoms_local;
442 adat_end = cu_nb->atdat->natoms;
445 /* beginning of timed D2H section */
448 stat = cudaEventRecord(t->start_nb_d2h[iloc], stream);
449 CU_RET_ERR(stat, "cudaEventRecord failed");
452 if (!cu_nb->bUseStreamSync)
454 /* For safety reasons set a few (5%) forces to NaN. This way even if the
455 polling "hack" fails with some future NVIDIA driver we'll get a crash. */
456 for (int i = adat_begin; i < 3*adat_end + 2; i += adat_len/20)
459 nbatom->out[0].f[i] = NAN;
462 if (numeric_limits<float>::has_quiet_NaN)
464 nbatom->out[0].f[i] = numeric_limits<float>::quiet_NaN();
469 nbatom->out[0].f[i] = GMX_REAL_MAX;
474 /* Set the last four bytes of the force array to a bit pattern
475 which can't be the result of the force calculation:
476 max exponent (127) and zero mantissa. */
477 *(unsigned int*)&nbatom->out[0].f[adat_end*3 - 1] = poll_wait_pattern;
480 /* With DD the local D2H transfer can only start after the non-local
481 has been launched. */
482 if (iloc == eintLocal && cu_nb->bUseTwoStreams)
484 stat = cudaStreamWaitEvent(stream, cu_nb->nonlocal_done, 0);
485 CU_RET_ERR(stat, "cudaStreamWaitEvent on nonlocal_done failed");
489 cu_copy_D2H_async(nbatom->out[0].f + adat_begin * 3, adat->f + adat_begin,
490 (adat_len)*sizeof(*adat->f), stream);
492 /* After the non-local D2H is launched the nonlocal_done event can be
493 recorded which signals that the local D2H can proceed. This event is not
494 placed after the non-local kernel because we first need the non-local
496 if (iloc == eintNonlocal)
498 stat = cudaEventRecord(cu_nb->nonlocal_done, stream);
499 CU_RET_ERR(stat, "cudaEventRecord on nonlocal_done failed");
502 /* only transfer energies in the local stream */
508 cu_copy_D2H_async(cu_nb->nbst.fshift, adat->fshift,
509 SHIFTS * sizeof(*cu_nb->nbst.fshift), stream);
515 cu_copy_D2H_async(cu_nb->nbst.e_lj, adat->e_lj,
516 sizeof(*cu_nb->nbst.e_lj), stream);
517 cu_copy_D2H_async(cu_nb->nbst.e_el, adat->e_el,
518 sizeof(*cu_nb->nbst.e_el), stream);
524 stat = cudaEventRecord(t->stop_nb_d2h[iloc], stream);
525 CU_RET_ERR(stat, "cudaEventRecord failed");
529 /* Atomic compare-exchange operation on unsigned values. It is used in
530 * polling wait for the GPU.
532 static inline bool atomic_cas(volatile unsigned int *ptr,
539 return tMPI_Atomic_cas((tMPI_Atomic_t *)ptr, oldval, newval);
541 gmx_incons("Atomic operations not available, atomic_cas() should not have been called!");
546 void nbnxn_cuda_wait_gpu(nbnxn_cuda_ptr_t cu_nb,
547 const nbnxn_atomdata_t *nbatom,
549 real *e_lj, real *e_el, rvec *fshift)
551 /* NOTE: only implemented for single-precision at this time */
553 int i, adat_end, iloc = -1;
554 volatile unsigned int *poll_word;
556 /* determine interaction locality from atom locality */
561 else if (NONLOCAL_A(aloc))
568 sprintf(stmp, "Invalid atom locality passed (%d); valid here is only "
569 "local (%d) or nonlocal (%d)", aloc, eatLocal, eatNonlocal);
573 cu_plist_t *plist = cu_nb->plist[iloc];
574 cu_timers_t *timers = cu_nb->timers;
575 wallclock_gpu_t *timings = cu_nb->timings;
576 nb_staging nbst = cu_nb->nbst;
578 bool bCalcEner = flags & GMX_FORCE_VIRIAL;
579 bool bCalcFshift = flags & GMX_FORCE_VIRIAL;
581 /* turn energy calculation always on/off (for debugging/testing only) */
582 bCalcEner = (bCalcEner || always_ener) && !never_ener;
584 /* don't launch wait/update timers & counters if there was no work to do
586 NOTE: if timing with multiple GPUs (streams) becomes possible, the
587 counters could end up being inconsistent due to not being incremented
588 on some of the nodes! */
589 if (cu_nb->plist[iloc]->nsci == 0)
594 /* calculate the atom data index range based on locality */
597 adat_end = cu_nb->atdat->natoms_local;
601 adat_end = cu_nb->atdat->natoms;
604 if (cu_nb->bUseStreamSync)
606 stat = cudaStreamSynchronize(cu_nb->stream[iloc]);
607 CU_RET_ERR(stat, "cudaStreamSynchronize failed in cu_blockwait_nb");
611 /* Busy-wait until we get the signal pattern set in last byte
612 * of the l/nl float vector. This pattern corresponds to a floating
613 * point number which can't be the result of the force calculation
614 * (maximum, 127 exponent and 0 mantissa).
615 * The polling uses atomic compare-exchange.
617 poll_word = (volatile unsigned int*)&nbatom->out[0].f[adat_end*3 - 1];
618 while (atomic_cas(poll_word, poll_wait_pattern, poll_wait_pattern))
623 /* timing data accumulation */
626 /* only increase counter once (at local F wait) */
630 timings->ktime[plist->bDoPrune ? 1 : 0][bCalcEner ? 1 : 0].c += 1;
634 timings->ktime[plist->bDoPrune ? 1 : 0][bCalcEner ? 1 : 0].t +=
635 cu_event_elapsed(timers->start_nb_k[iloc], timers->stop_nb_k[iloc]);
637 /* X/q H2D and F D2H timings */
638 timings->nb_h2d_t += cu_event_elapsed(timers->start_nb_h2d[iloc],
639 timers->stop_nb_h2d[iloc]);
640 timings->nb_d2h_t += cu_event_elapsed(timers->start_nb_d2h[iloc],
641 timers->stop_nb_d2h[iloc]);
643 /* only count atdat and pair-list H2D at pair-search step */
646 /* atdat transfer timing (add only once, at local F wait) */
650 timings->pl_h2d_t += cu_event_elapsed(timers->start_atdat,
654 timings->pl_h2d_t += cu_event_elapsed(timers->start_pl_h2d[iloc],
655 timers->stop_pl_h2d[iloc]);
659 /* add up energies and shift forces (only once at local F wait) */
670 for (i = 0; i < SHIFTS; i++)
672 fshift[i][0] += nbst.fshift[i].x;
673 fshift[i][1] += nbst.fshift[i].y;
674 fshift[i][2] += nbst.fshift[i].z;
679 /* turn off pruning (doesn't matter if this is pair-search step or not) */
680 plist->bDoPrune = false;
683 /*! Return the reference to the nbfp texture. */
684 const struct texture<float, 1, cudaReadModeElementType> &nbnxn_cuda_get_nbfp_texref()
689 /*! Return the reference to the nbfp_comb texture. */
690 const struct texture<float, 1, cudaReadModeElementType> &nbnxn_cuda_get_nbfp_comb_texref()
692 return nbfp_comb_texref;
695 /*! Return the reference to the coulomb_tab. */
696 const struct texture<float, 1, cudaReadModeElementType> &nbnxn_cuda_get_coulomb_tab_texref()
698 return coulomb_tab_texref;
701 /*! Set up the cache configuration for the non-bonded kernels,
703 void nbnxn_cuda_set_cacheconfig(cuda_dev_info_t *devinfo)
707 for (int i = 0; i < eelCuNR; i++)
709 for (int j = 0; j < evdwCuNR; j++)
711 if (devinfo->prop.major >= 3)
713 /* Default kernel on sm 3.x 48/16 kB Shared/L1 */
714 stat = cudaFuncSetCacheConfig(nb_kfunc_ener_prune_ptr[i][j], cudaFuncCachePreferShared);
715 stat = cudaFuncSetCacheConfig(nb_kfunc_ener_noprune_ptr[i][j], cudaFuncCachePreferShared);
716 stat = cudaFuncSetCacheConfig(nb_kfunc_noener_prune_ptr[i][j], cudaFuncCachePreferShared);
717 stat = cudaFuncSetCacheConfig(nb_kfunc_noener_noprune_ptr[i][j], cudaFuncCachePreferShared);
721 /* On Fermi prefer L1 gives 2% higher performance */
722 /* Default kernel on sm_2.x 16/48 kB Shared/L1 */
723 stat = cudaFuncSetCacheConfig(nb_kfunc_ener_prune_ptr[i][j], cudaFuncCachePreferL1);
724 stat = cudaFuncSetCacheConfig(nb_kfunc_ener_noprune_ptr[i][j], cudaFuncCachePreferL1);
725 stat = cudaFuncSetCacheConfig(nb_kfunc_noener_prune_ptr[i][j], cudaFuncCachePreferL1);
726 stat = cudaFuncSetCacheConfig(nb_kfunc_noener_noprune_ptr[i][j], cudaFuncCachePreferL1);
728 CU_RET_ERR(stat, "cudaFuncSetCacheConfig failed");