Actual source code: feopencl.c

  1: #include <petsc/private/petscfeimpl.h>

  3: #if defined(PETSC_HAVE_OPENCL)

  5: static PetscErrorCode PetscFEDestroy_OpenCL(PetscFE fem)
  6: {
  7:   PetscFE_OpenCL *ocl = (PetscFE_OpenCL *)fem->data;

  9:   PetscFunctionBegin;
 10:   PetscCall(clReleaseCommandQueue(ocl->queue_id));
 11:   ocl->queue_id = 0;
 12:   PetscCall(clReleaseContext(ocl->ctx_id));
 13:   ocl->ctx_id = 0;
 14:   PetscCall(PetscFree(ocl));
 15:   PetscFunctionReturn(PETSC_SUCCESS);
 16: }

 18:   #define PetscCallSTR(err) \
 19:     do { \
 20:       PetscCall(err); \
 21:       string_tail += count; \
 22:       PetscCheck(string_tail != end_of_buffer, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Buffer overflow"); \
 23:     } while (0)
 24: enum {
 25:   LAPLACIAN  = 0,
 26:   ELASTICITY = 1
 27: };

 29: /* NOTE: This is now broken for vector problems. Must redo loops to respect vector basis elements */
 30: /* dim     Number of spatial dimensions:          2                   */
 31: /* N_b     Number of basis functions:             generated           */
 32: /* N_{bt}  Number of total basis functions:       N_b * N_{comp}      */
 33: /* N_q     Number of quadrature points:           generated           */
 34: /* N_{bs}  Number of block cells                  LCM(N_b, N_q)       */
 35: /* N_{bst} Number of block cell components        LCM(N_{bt}, N_q)    */
 36: /* N_{bl}  Number of concurrent blocks            generated           */
 37: /* N_t     Number of threads:                     N_{bl} * N_{bs}     */
 38: /* N_{cbc} Number of concurrent basis      cells: N_{bl} * N_q        */
 39: /* N_{cqc} Number of concurrent quadrature cells: N_{bl} * N_b        */
 40: /* N_{sbc} Number of serial     basis      cells: N_{bs} / N_q        */
 41: /* N_{sqc} Number of serial     quadrature cells: N_{bs} / N_b        */
 42: /* N_{cb}  Number of serial cell batches:         input               */
 43: /* N_c     Number of total cells:                 N_{cb}*N_{t}/N_{comp} */
 44: static PetscErrorCode PetscFEOpenCLGenerateIntegrationCode(PetscFE fem, char **string_buffer, PetscInt buffer_length, PetscBool useAux, PetscInt N_bl)
 45: {
 46:   PetscFE_OpenCL  *ocl = (PetscFE_OpenCL *)fem->data;
 47:   PetscQuadrature  q;
 48:   char            *string_tail   = *string_buffer;
 49:   char            *end_of_buffer = *string_buffer + buffer_length;
 50:   char             float_str[] = "float", double_str[] = "double";
 51:   char            *numeric_str    = &(float_str[0]);
 52:   PetscInt         op             = ocl->op;
 53:   PetscBool        useField       = PETSC_FALSE;
 54:   PetscBool        useFieldDer    = PETSC_TRUE;
 55:   PetscBool        useFieldAux    = useAux;
 56:   PetscBool        useFieldDerAux = PETSC_FALSE;
 57:   PetscBool        useF0          = PETSC_TRUE;
 58:   PetscBool        useF1          = PETSC_TRUE;
 59:   const PetscReal *points, *weights;
 60:   PetscTabulation  T;
 61:   PetscInt         dim, qNc, N_b, N_c, N_q, N_t, p, d, b, c;
 62:   size_t           count;

 64:   PetscFunctionBegin;
 65:   PetscCall(PetscFEGetSpatialDimension(fem, &dim));
 66:   PetscCall(PetscFEGetDimension(fem, &N_b));
 67:   PetscCall(PetscFEGetNumComponents(fem, &N_c));
 68:   PetscCall(PetscFEGetQuadrature(fem, &q));
 69:   PetscCall(PetscQuadratureGetData(q, NULL, &qNc, &N_q, &points, &weights));
 70:   PetscCheck(qNc == 1, PETSC_COMM_SELF, PETSC_ERR_SUP, "Only supports scalar quadrature, not %" PetscInt_FMT " components", qNc);
 71:   N_t = N_b * N_c * N_q * N_bl;
 72:   /* Enable device extension for double precision */
 73:   if (ocl->realType == PETSC_DOUBLE) {
 74:     PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
 75:                                     "#if defined(cl_khr_fp64)\n"
 76:                                     "#  pragma OPENCL EXTENSION cl_khr_fp64: enable\n"
 77:                                     "#elif defined(cl_amd_fp64)\n"
 78:                                     "#  pragma OPENCL EXTENSION cl_amd_fp64: enable\n"
 79:                                     "#endif\n",
 80:                                     &count));
 81:     numeric_str = &(double_str[0]);
 82:   }
 83:   /* Kernel API */
 84:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
 85:                                   "\n"
 86:                                   "__kernel void integrateElementQuadrature(int N_cb, __global %s *coefficients, __global %s *coefficientsAux, __global %s *jacobianInverses, __global %s *jacobianDeterminants, __global %s *elemVec)\n"
 87:                                   "{\n",
 88:                                   &count, numeric_str, numeric_str, numeric_str, numeric_str, numeric_str));
 89:   /* Quadrature */
 90:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
 91:                                   "  /* Quadrature points\n"
 92:                                   "   - (x1,y1,x2,y2,...) */\n"
 93:                                   "  const %s points[%d] = {\n",
 94:                                   &count, numeric_str, N_q * dim));
 95:   for (p = 0; p < N_q; ++p) {
 96:     for (d = 0; d < dim; ++d) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "%g,\n", &count, points[p * dim + d]));
 97:   }
 98:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "};\n", &count));
 99:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
100:                                   "  /* Quadrature weights\n"
101:                                   "   - (v1,v2,...) */\n"
102:                                   "  const %s weights[%d] = {\n",
103:                                   &count, numeric_str, N_q));
104:   for (p = 0; p < N_q; ++p) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "%g,\n", &count, weights[p]));
105:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "};\n", &count));
106:   /* Basis Functions */
107:   PetscCall(PetscFEGetCellTabulation(fem, 1, &T));
108:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
109:                                   "  /* Nodal basis function evaluations\n"
110:                                   "    - basis component is fastest varying, the basis function, then point */\n"
111:                                   "  const %s Basis[%d] = {\n",
112:                                   &count, numeric_str, N_q * N_b * N_c));
113:   for (p = 0; p < N_q; ++p) {
114:     for (b = 0; b < N_b; ++b) {
115:       for (c = 0; c < N_c; ++c) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "%g,\n", &count, T->T[0][(p * N_b + b) * N_c + c]));
116:     }
117:   }
118:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "};\n", &count));
119:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
120:                                   "\n"
121:                                   "  /* Nodal basis function derivative evaluations,\n"
122:                                   "      - derivative direction is fastest varying, then basis component, then basis function, then point */\n"
123:                                   "  const %s%d BasisDerivatives[%d] = {\n",
124:                                   &count, numeric_str, dim, N_q * N_b * N_c));
125:   for (p = 0; p < N_q; ++p) {
126:     for (b = 0; b < N_b; ++b) {
127:       for (c = 0; c < N_c; ++c) {
128:         PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "(%s%d)(", &count, numeric_str, dim));
129:         for (d = 0; d < dim; ++d) {
130:           if (d > 0) {
131:             PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, ", %g", &count, T->T[1][((p * N_b + b) * dim + d) * N_c + c]));
132:           } else {
133:             PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "%g", &count, T->T[1][((p * N_b + b) * dim + d) * N_c + c]));
134:           }
135:         }
136:         PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "),\n", &count));
137:       }
138:     }
139:   }
140:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "};\n", &count));
141:   /* Sizes */
142:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
143:                                   "  const int dim    = %d;                           // The spatial dimension\n"
144:                                   "  const int N_bl   = %d;                           // The number of concurrent blocks\n"
145:                                   "  const int N_b    = %d;                           // The number of basis functions\n"
146:                                   "  const int N_comp = %d;                           // The number of basis function components\n"
147:                                   "  const int N_bt   = N_b*N_comp;                    // The total number of scalar basis functions\n"
148:                                   "  const int N_q    = %d;                           // The number of quadrature points\n"
149:                                   "  const int N_bst  = N_bt*N_q;                      // The block size, LCM(N_b*N_comp, N_q), Notice that a block is not processed simultaneously\n"
150:                                   "  const int N_t    = N_bst*N_bl;                    // The number of threads, N_bst * N_bl\n"
151:                                   "  const int N_bc   = N_t/N_comp;                    // The number of cells per batch (N_b*N_q*N_bl)\n"
152:                                   "  const int N_sbc  = N_bst / (N_q * N_comp);\n"
153:                                   "  const int N_sqc  = N_bst / N_bt;\n"
154:                                   "  /*const int N_c    = N_cb * N_bc;*/\n"
155:                                   "\n"
156:                                   "  /* Calculated indices */\n"
157:                                   "  /*const int tidx    = get_local_id(0) + get_local_size(0)*get_local_id(1);*/\n"
158:                                   "  const int tidx    = get_local_id(0);\n"
159:                                   "  const int blidx   = tidx / N_bst;                  // Block number for this thread\n"
160:                                   "  const int bidx    = tidx %% N_bt;                   // Basis function mapped to this thread\n"
161:                                   "  const int cidx    = tidx %% N_comp;                 // Basis component mapped to this thread\n"
162:                                   "  const int qidx    = tidx %% N_q;                    // Quadrature point mapped to this thread\n"
163:                                   "  const int blbidx  = tidx %% N_q + blidx*N_q;        // Cell mapped to this thread in the basis phase\n"
164:                                   "  const int blqidx  = tidx %% N_b + blidx*N_b;        // Cell mapped to this thread in the quadrature phase\n"
165:                                   "  const int gidx    = get_group_id(1)*get_num_groups(0) + get_group_id(0);\n"
166:                                   "  const int Goffset = gidx*N_cb*N_bc;\n",
167:                                   &count, dim, N_bl, N_b, N_c, N_q));
168:   /* Local memory */
169:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
170:                                   "\n"
171:                                   "  /* Quadrature data */\n"
172:                                   "  %s                w;                   // $w_q$, Quadrature weight at $x_q$\n"
173:                                   "  __local %s         phi_i[%d];    //[N_bt*N_q];  // $\\phi_i(x_q)$, Value of the basis function $i$ at $x_q$\n"
174:                                   "  __local %s%d       phiDer_i[%d]; //[N_bt*N_q];  // $\\frac{\\partial\\phi_i(x_q)}{\\partial x_d}$, Value of the derivative of basis function $i$ in direction $x_d$ at $x_q$\n"
175:                                   "  /* Geometric data */\n"
176:                                   "  __local %s        detJ[%d]; //[N_t];           // $|J(x_q)|$, Jacobian determinant at $x_q$\n"
177:                                   "  __local %s        invJ[%d];//[N_t*dim*dim];   // $J^{-1}(x_q)$, Jacobian inverse at $x_q$\n",
178:                                   &count, numeric_str, numeric_str, N_b * N_c * N_q, numeric_str, dim, N_b * N_c * N_q, numeric_str, N_t, numeric_str, N_t * dim * dim));
179:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
180:                                   "  /* FEM data */\n"
181:                                   "  __local %s        u_i[%d]; //[N_t*N_bt];       // Coefficients $u_i$ of the field $u|_{\\mathcal{T}} = \\sum_i u_i \\phi_i$\n",
182:                                   &count, numeric_str, N_t * N_b * N_c));
183:   if (useAux) {
184:     PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "  __local %s        a_i[%d]; //[N_t];            // Coefficients $a_i$ of the auxiliary field $a|_{\\mathcal{T}} = \\sum_i a_i \\phi^R_i$\n", &count, numeric_str, N_t));
185:   }
186:   if (useF0) {
187:     PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
188:                                     "  /* Intermediate calculations */\n"
189:                                     "  __local %s         f_0[%d]; //[N_t*N_sqc];      // $f_0(u(x_q), \\nabla u(x_q)) |J(x_q)| w_q$\n",
190:                                     &count, numeric_str, N_t * N_q));
191:   }
192:   if (useF1) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "  __local %s%d       f_1[%d]; //[N_t*N_sqc];      // $f_1(u(x_q), \\nabla u(x_q)) |J(x_q)| w_q$\n", &count, numeric_str, dim, N_t * N_q));
193:   /* TODO: If using elasticity, put in mu/lambda coefficients */
194:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
195:                                   "  /* Output data */\n"
196:                                   "  %s                e_i;                 // Coefficient $e_i$ of the residual\n\n",
197:                                   &count, numeric_str));
198:   /* One-time loads */
199:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
200:                                   "  /* These should be generated inline */\n"
201:                                   "  /* Load quadrature weights */\n"
202:                                   "  w = weights[qidx];\n"
203:                                   "  /* Load basis tabulation \\phi_i for this cell */\n"
204:                                   "  if (tidx < N_bt*N_q) {\n"
205:                                   "    phi_i[tidx]    = Basis[tidx];\n"
206:                                   "    phiDer_i[tidx] = BasisDerivatives[tidx];\n"
207:                                   "  }\n\n",
208:                                   &count));
209:   /* Batch loads */
210:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
211:                                   "  for (int batch = 0; batch < N_cb; ++batch) {\n"
212:                                   "    /* Load geometry */\n"
213:                                   "    detJ[tidx] = jacobianDeterminants[Goffset+batch*N_bc+tidx];\n"
214:                                   "    for (int n = 0; n < dim*dim; ++n) {\n"
215:                                   "      const int offset = n*N_t;\n"
216:                                   "      invJ[offset+tidx] = jacobianInverses[(Goffset+batch*N_bc)*dim*dim+offset+tidx];\n"
217:                                   "    }\n"
218:                                   "    /* Load coefficients u_i for this cell */\n"
219:                                   "    for (int n = 0; n < N_bt; ++n) {\n"
220:                                   "      const int offset = n*N_t;\n"
221:                                   "      u_i[offset+tidx] = coefficients[(Goffset*N_bt)+batch*N_t*N_b+offset+tidx];\n"
222:                                   "    }\n",
223:                                   &count));
224:   if (useAux) {
225:     PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
226:                                     "    /* Load coefficients a_i for this cell */\n"
227:                                     "    /* TODO: This should not be N_t here, it should be N_bc*N_comp_aux */\n"
228:                                     "    a_i[tidx] = coefficientsAux[Goffset+batch*N_t+tidx];\n",
229:                                     &count));
230:   }
231:   /* Quadrature phase */
232:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
233:                                   "    barrier(CLK_LOCAL_MEM_FENCE);\n"
234:                                   "\n"
235:                                   "    /* Map coefficients to values at quadrature points */\n"
236:                                   "    for (int c = 0; c < N_sqc; ++c) {\n"
237:                                   "      const int cell          = c*N_bl*N_b + blqidx;\n"
238:                                   "      const int fidx          = (cell*N_q + qidx)*N_comp + cidx;\n",
239:                                   &count));
240:   if (useField) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      %s  u[%d]; //[N_comp];     // $u(x_q)$, Value of the field at $x_q$\n", &count, numeric_str, N_c));
241:   if (useFieldDer) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      %s%d   gradU[%d]; //[N_comp]; // $\\nabla u(x_q)$, Value of the field gradient at $x_q$\n", &count, numeric_str, dim, N_c));
242:   if (useFieldAux) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      %s  a[%d]; //[1];     // $a(x_q)$, Value of the auxiliary fields at $x_q$\n", &count, numeric_str, 1));
243:   if (useFieldDerAux) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      %s%d   gradA[%d]; //[1]; // $\\nabla a(x_q)$, Value of the auxiliary field gradient at $x_q$\n", &count, numeric_str, dim, 1));
244:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
245:                                   "\n"
246:                                   "      for (int comp = 0; comp < N_comp; ++comp) {\n",
247:                                   &count));
248:   if (useField) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "        u[comp] = 0.0;\n", &count));
249:   if (useFieldDer) {
250:     switch (dim) {
251:     case 1:
252:       PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "        gradU[comp].x = 0.0;\n", &count));
253:       break;
254:     case 2:
255:       PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "        gradU[comp].x = 0.0; gradU[comp].y = 0.0;\n", &count));
256:       break;
257:     case 3:
258:       PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "        gradU[comp].x = 0.0; gradU[comp].y = 0.0; gradU[comp].z = 0.0;\n", &count));
259:       break;
260:     }
261:   }
262:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      }\n", &count));
263:   if (useFieldAux) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      a[0] = 0.0;\n", &count));
264:   if (useFieldDerAux) {
265:     switch (dim) {
266:     case 1:
267:       PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      gradA[0].x = 0.0;\n", &count));
268:       break;
269:     case 2:
270:       PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      gradA[0].x = 0.0; gradA[0].y = 0.0;\n", &count));
271:       break;
272:     case 3:
273:       PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      gradA[0].x = 0.0; gradA[0].y = 0.0; gradA[0].z = 0.0;\n", &count));
274:       break;
275:     }
276:   }
277:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
278:                                   "      /* Get field and derivatives at this quadrature point */\n"
279:                                   "      for (int i = 0; i < N_b; ++i) {\n"
280:                                   "        for (int comp = 0; comp < N_comp; ++comp) {\n"
281:                                   "          const int b    = i*N_comp+comp;\n"
282:                                   "          const int pidx = qidx*N_bt + b;\n"
283:                                   "          const int uidx = cell*N_bt + b;\n"
284:                                   "          %s%d   realSpaceDer;\n\n",
285:                                   &count, numeric_str, dim));
286:   if (useField) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "          u[comp] += u_i[uidx]*phi_i[pidx];\n", &count));
287:   if (useFieldDer) {
288:     switch (dim) {
289:     case 2:
290:       PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
291:                                       "          realSpaceDer.x = invJ[cell*dim*dim+0*dim+0]*phiDer_i[pidx].x + invJ[cell*dim*dim+1*dim+0]*phiDer_i[pidx].y;\n"
292:                                       "          gradU[comp].x += u_i[uidx]*realSpaceDer.x;\n"
293:                                       "          realSpaceDer.y = invJ[cell*dim*dim+0*dim+1]*phiDer_i[pidx].x + invJ[cell*dim*dim+1*dim+1]*phiDer_i[pidx].y;\n"
294:                                       "          gradU[comp].y += u_i[uidx]*realSpaceDer.y;\n",
295:                                       &count));
296:       break;
297:     case 3:
298:       PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
299:                                       "          realSpaceDer.x = invJ[cell*dim*dim+0*dim+0]*phiDer_i[pidx].x + invJ[cell*dim*dim+1*dim+0]*phiDer_i[pidx].y + invJ[cell*dim*dim+2*dim+0]*phiDer_i[pidx].z;\n"
300:                                       "          gradU[comp].x += u_i[uidx]*realSpaceDer.x;\n"
301:                                       "          realSpaceDer.y = invJ[cell*dim*dim+0*dim+1]*phiDer_i[pidx].x + invJ[cell*dim*dim+1*dim+1]*phiDer_i[pidx].y + invJ[cell*dim*dim+2*dim+1]*phiDer_i[pidx].z;\n"
302:                                       "          gradU[comp].y += u_i[uidx]*realSpaceDer.y;\n"
303:                                       "          realSpaceDer.z = invJ[cell*dim*dim+0*dim+2]*phiDer_i[pidx].x + invJ[cell*dim*dim+1*dim+2]*phiDer_i[pidx].y + invJ[cell*dim*dim+2*dim+2]*phiDer_i[pidx].z;\n"
304:                                       "          gradU[comp].z += u_i[uidx]*realSpaceDer.z;\n",
305:                                       &count));
306:       break;
307:     }
308:   }
309:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
310:                                   "        }\n"
311:                                   "      }\n",
312:                                   &count));
313:   if (useFieldAux) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "          a[0] += a_i[cell];\n", &count));
314:   /* Calculate residual at quadrature points: Should be generated by an weak form egine */
315:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      /* Process values at quadrature points */\n", &count));
316:   switch (op) {
317:   case LAPLACIAN:
318:     if (useF0) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      f_0[fidx] = 4.0;\n", &count));
319:     if (useF1) {
320:       if (useAux) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      f_1[fidx] = a[0]*gradU[cidx];\n", &count));
321:       else PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      f_1[fidx] = gradU[cidx];\n", &count));
322:     }
323:     break;
324:   case ELASTICITY:
325:     if (useF0) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      f_0[fidx] = 4.0;\n", &count));
326:     if (useF1) {
327:       switch (dim) {
328:       case 2:
329:         PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
330:                                         "      switch (cidx) {\n"
331:                                         "      case 0:\n"
332:                                         "        f_1[fidx].x = lambda*(gradU[0].x + gradU[1].y) + mu*(gradU[0].x + gradU[0].x);\n"
333:                                         "        f_1[fidx].y = lambda*(gradU[0].x + gradU[1].y) + mu*(gradU[0].y + gradU[1].x);\n"
334:                                         "        break;\n"
335:                                         "      case 1:\n"
336:                                         "        f_1[fidx].x = lambda*(gradU[0].x + gradU[1].y) + mu*(gradU[1].x + gradU[0].y);\n"
337:                                         "        f_1[fidx].y = lambda*(gradU[0].x + gradU[1].y) + mu*(gradU[1].y + gradU[1].y);\n"
338:                                         "      }\n",
339:                                         &count));
340:         break;
341:       case 3:
342:         PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
343:                                         "      switch (cidx) {\n"
344:                                         "      case 0:\n"
345:                                         "        f_1[fidx].x = lambda*(gradU[0].x + gradU[1].y + gradU[2].z) + mu*(gradU[0].x + gradU[0].x);\n"
346:                                         "        f_1[fidx].y = lambda*(gradU[0].x + gradU[1].y + gradU[2].z) + mu*(gradU[0].y + gradU[1].x);\n"
347:                                         "        f_1[fidx].z = lambda*(gradU[0].x + gradU[1].y + gradU[2].z) + mu*(gradU[0].z + gradU[2].x);\n"
348:                                         "        break;\n"
349:                                         "      case 1:\n"
350:                                         "        f_1[fidx].x = lambda*(gradU[0].x + gradU[1].y + gradU[2].z) + mu*(gradU[1].x + gradU[0].y);\n"
351:                                         "        f_1[fidx].y = lambda*(gradU[0].x + gradU[1].y + gradU[2].z) + mu*(gradU[1].y + gradU[1].y);\n"
352:                                         "        f_1[fidx].z = lambda*(gradU[0].x + gradU[1].y + gradU[2].z) + mu*(gradU[1].y + gradU[2].y);\n"
353:                                         "        break;\n"
354:                                         "      case 2:\n"
355:                                         "        f_1[fidx].x = lambda*(gradU[0].x + gradU[1].y + gradU[2].z) + mu*(gradU[2].x + gradU[0].z);\n"
356:                                         "        f_1[fidx].y = lambda*(gradU[0].x + gradU[1].y + gradU[2].z) + mu*(gradU[2].y + gradU[1].z);\n"
357:                                         "        f_1[fidx].z = lambda*(gradU[0].x + gradU[1].y + gradU[2].z) + mu*(gradU[2].y + gradU[2].z);\n"
358:                                         "      }\n",
359:                                         &count));
360:         break;
361:       }
362:     }
363:     break;
364:   default:
365:     SETERRQ(PETSC_COMM_SELF, PETSC_ERR_SUP, "PDE operator %d is not supported", op);
366:   }
367:   if (useF0) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      f_0[fidx] *= detJ[cell]*w;\n", &count));
368:   if (useF1) {
369:     switch (dim) {
370:     case 1:
371:       PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      f_1[fidx].x *= detJ[cell]*w;\n", &count));
372:       break;
373:     case 2:
374:       PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      f_1[fidx].x *= detJ[cell]*w; f_1[fidx].y *= detJ[cell]*w;\n", &count));
375:       break;
376:     case 3:
377:       PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "      f_1[fidx].x *= detJ[cell]*w; f_1[fidx].y *= detJ[cell]*w; f_1[fidx].z *= detJ[cell]*w;\n", &count));
378:       break;
379:     }
380:   }
381:   /* Thread transpose */
382:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
383:                                   "    }\n\n"
384:                                   "    /* ==== TRANSPOSE THREADS ==== */\n"
385:                                   "    barrier(CLK_LOCAL_MEM_FENCE);\n\n",
386:                                   &count));
387:   /* Basis phase */
388:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
389:                                   "    /* Map values at quadrature points to coefficients */\n"
390:                                   "    for (int c = 0; c < N_sbc; ++c) {\n"
391:                                   "      const int cell = c*N_bl*N_q + blbidx; /* Cell number in batch */\n"
392:                                   "\n"
393:                                   "      e_i = 0.0;\n"
394:                                   "      for (int q = 0; q < N_q; ++q) {\n"
395:                                   "        const int pidx = q*N_bt + bidx;\n"
396:                                   "        const int fidx = (cell*N_q + q)*N_comp + cidx;\n"
397:                                   "        %s%d   realSpaceDer;\n\n",
398:                                   &count, numeric_str, dim));

400:   if (useF0) PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail, "        e_i += phi_i[pidx]*f_0[fidx];\n", &count));
401:   if (useF1) {
402:     switch (dim) {
403:     case 2:
404:       PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
405:                                       "        realSpaceDer.x = invJ[cell*dim*dim+0*dim+0]*phiDer_i[pidx].x + invJ[cell*dim*dim+1*dim+0]*phiDer_i[pidx].y;\n"
406:                                       "        e_i           += realSpaceDer.x*f_1[fidx].x;\n"
407:                                       "        realSpaceDer.y = invJ[cell*dim*dim+0*dim+1]*phiDer_i[pidx].x + invJ[cell*dim*dim+1*dim+1]*phiDer_i[pidx].y;\n"
408:                                       "        e_i           += realSpaceDer.y*f_1[fidx].y;\n",
409:                                       &count));
410:       break;
411:     case 3:
412:       PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
413:                                       "        realSpaceDer.x = invJ[cell*dim*dim+0*dim+0]*phiDer_i[pidx].x + invJ[cell*dim*dim+1*dim+0]*phiDer_i[pidx].y + invJ[cell*dim*dim+2*dim+0]*phiDer_i[pidx].z;\n"
414:                                       "        e_i           += realSpaceDer.x*f_1[fidx].x;\n"
415:                                       "        realSpaceDer.y = invJ[cell*dim*dim+0*dim+1]*phiDer_i[pidx].x + invJ[cell*dim*dim+1*dim+1]*phiDer_i[pidx].y + invJ[cell*dim*dim+2*dim+1]*phiDer_i[pidx].z;\n"
416:                                       "        e_i           += realSpaceDer.y*f_1[fidx].y;\n"
417:                                       "        realSpaceDer.z = invJ[cell*dim*dim+0*dim+2]*phiDer_i[pidx].x + invJ[cell*dim*dim+1*dim+2]*phiDer_i[pidx].y + invJ[cell*dim*dim+2*dim+2]*phiDer_i[pidx].z;\n"
418:                                       "        e_i           += realSpaceDer.z*f_1[fidx].z;\n",
419:                                       &count));
420:       break;
421:     }
422:   }
423:   PetscCallSTR(PetscSNPrintfCount(string_tail, end_of_buffer - string_tail,
424:                                   "      }\n"
425:                                   "      /* Write element vector for N_{cbc} cells at a time */\n"
426:                                   "      elemVec[(Goffset + batch*N_bc + c*N_bl*N_q)*N_bt + tidx] = e_i;\n"
427:                                   "    }\n"
428:                                   "    /* ==== Could do one write per batch ==== */\n"
429:                                   "  }\n"
430:                                   "  return;\n"
431:                                   "}\n",
432:                                   &count));
433:   PetscFunctionReturn(PETSC_SUCCESS);
434: }

436: static PetscErrorCode PetscFEOpenCLGetIntegrationKernel(PetscFE fem, PetscBool useAux, cl_program *ocl_prog, cl_kernel *ocl_kernel)
437: {
438:   PetscFE_OpenCL *ocl = (PetscFE_OpenCL *)fem->data;
439:   PetscInt        dim, N_bl;
440:   PetscBool       flg;
441:   char           *buffer;
442:   size_t          len;
443:   char            errMsg[8192];
444:   cl_int          err;

446:   PetscFunctionBegin;
447:   PetscCall(PetscFEGetSpatialDimension(fem, &dim));
448:   PetscCall(PetscMalloc1(8192, &buffer));
449:   PetscCall(PetscFEGetTileSizes(fem, NULL, &N_bl, NULL, NULL));
450:   PetscCall(PetscFEOpenCLGenerateIntegrationCode(fem, &buffer, 8192, useAux, N_bl));
451:   PetscCall(PetscOptionsHasName(((PetscObject)fem)->options, ((PetscObject)fem)->prefix, "-petscfe_opencl_kernel_print", &flg));
452:   if (flg) PetscCall(PetscPrintf(PetscObjectComm((PetscObject)fem), "OpenCL FE Integration Kernel:\n%s\n", buffer));
453:   PetscCall(PetscStrlen(buffer, &len));
454:   *ocl_prog = clCreateProgramWithSource(ocl->ctx_id, 1, (const char **)&buffer, &len, &err);
455:   PetscCall(err);
456:   err = clBuildProgram(*ocl_prog, 0, NULL, NULL, NULL, NULL);
457:   if (err != CL_SUCCESS) {
458:     err = clGetProgramBuildInfo(*ocl_prog, ocl->dev_id, CL_PROGRAM_BUILD_LOG, 8192 * sizeof(char), &errMsg, NULL);
459:     SETERRQ(PETSC_COMM_SELF, PETSC_ERR_PLIB, "Build failed! Log:\n %s", errMsg);
460:   }
461:   PetscCall(PetscFree(buffer));
462:   *ocl_kernel = clCreateKernel(*ocl_prog, "integrateElementQuadrature", &err);
463:   PetscFunctionReturn(PETSC_SUCCESS);
464: }

466: static PetscErrorCode PetscFEOpenCLCalculateGrid(PetscFE fem, PetscInt N, PetscInt blockSize, size_t *x, size_t *y, size_t *z)
467: {
468:   const PetscInt Nblocks = N / blockSize;

470:   PetscFunctionBegin;
471:   PetscCheck(!(N % blockSize), PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Invalid block size %d for %d elements", blockSize, N);
472:   *z = 1;
473:   *y = 1;
474:   for (*x = (size_t)(PetscSqrtReal(Nblocks) + 0.5); *x > 0; --*x) {
475:     *y = Nblocks / *x;
476:     if (*x * *y == (size_t)Nblocks) break;
477:   }
478:   PetscCheck(*x * *y == (size_t)Nblocks, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Could not find partition for %" PetscInt_FMT " with block size %" PetscInt_FMT, N, blockSize);
479:   PetscFunctionReturn(PETSC_SUCCESS);
480: }

482: static PetscErrorCode PetscFEOpenCLLogResidual(PetscFE fem, PetscLogDouble time, PetscLogDouble flops)
483: {
484:   PetscFE_OpenCL   *ocl = (PetscFE_OpenCL *)fem->data;
485:   PetscStageLog     stageLog;
486:   PetscEventPerfLog eventLog = NULL;
487:   int               stage;

489:   PetscFunctionBegin;
490:   PetscCall(PetscLogGetStageLog(&stageLog));
491:   PetscCall(PetscStageLogGetCurrent(stageLog, &stage));
492:   PetscCall(PetscStageLogGetEventPerfLog(stageLog, stage, &eventLog));
493:   /* Log performance info */
494:   eventLog->eventInfo[ocl->residualEvent].count++;
495:   eventLog->eventInfo[ocl->residualEvent].time += time;
496:   eventLog->eventInfo[ocl->residualEvent].flops += flops;
497:   PetscFunctionReturn(PETSC_SUCCESS);
498: }

500: static PetscErrorCode PetscFEIntegrateResidual_OpenCL(PetscDS prob, PetscFormKey key, PetscInt Ne, PetscFEGeom *cgeom, const PetscScalar coefficients[], const PetscScalar coefficients_t[], PetscDS probAux, const PetscScalar coefficientsAux[], PetscReal t, PetscScalar elemVec[])
501: {
502:   /* Nbc = batchSize */
503:   PetscFE         fem;
504:   PetscFE_OpenCL *ocl;
505:   PetscPointFunc  f0_func;
506:   PetscPointFunc  f1_func;
507:   PetscQuadrature q;
508:   PetscInt        dim, qNc;
509:   PetscInt        N_b;    /* The number of basis functions */
510:   PetscInt        N_comp; /* The number of basis function components */
511:   PetscInt        N_bt;   /* The total number of scalar basis functions */
512:   PetscInt        N_q;    /* The number of quadrature points */
513:   PetscInt        N_bst;  /* The block size, LCM(N_bt, N_q), Notice that a block is not process simultaneously */
514:   PetscInt        N_t;    /* The number of threads, N_bst * N_bl */
515:   PetscInt        N_bl;   /* The number of blocks */
516:   PetscInt        N_bc;   /* The batch size, N_bl*N_q*N_b */
517:   PetscInt        N_cb;   /* The number of batches */
518:   const PetscInt  field = key.field;
519:   PetscInt        numFlops, f0Flops = 0, f1Flops = 0;
520:   PetscBool       useAux      = probAux ? PETSC_TRUE : PETSC_FALSE;
521:   PetscBool       useField    = PETSC_FALSE;
522:   PetscBool       useFieldDer = PETSC_TRUE;
523:   PetscBool       useF0       = PETSC_TRUE;
524:   PetscBool       useF1       = PETSC_TRUE;
525:   /* OpenCL variables */
526:   cl_program       ocl_prog;
527:   cl_kernel        ocl_kernel;
528:   cl_event         ocl_ev;   /* The event for tracking kernel execution */
529:   cl_ulong         ns_start; /* Nanoseconds counter on GPU at kernel start */
530:   cl_ulong         ns_end;   /* Nanoseconds counter on GPU at kernel stop */
531:   cl_mem           o_jacobianInverses, o_jacobianDeterminants;
532:   cl_mem           o_coefficients, o_coefficientsAux, o_elemVec;
533:   float           *f_coeff = NULL, *f_coeffAux = NULL, *f_invJ = NULL, *f_detJ = NULL;
534:   double          *d_coeff = NULL, *d_coeffAux = NULL, *d_invJ = NULL, *d_detJ = NULL;
535:   PetscReal       *r_invJ = NULL, *r_detJ = NULL;
536:   void            *oclCoeff, *oclCoeffAux, *oclInvJ, *oclDetJ;
537:   size_t           local_work_size[3], global_work_size[3];
538:   size_t           realSize, x, y, z;
539:   const PetscReal *points, *weights;
540:   int              err;

542:   PetscFunctionBegin;
543:   PetscCall(PetscDSGetDiscretization(prob, field, (PetscObject *)&fem));
544:   ocl = (PetscFE_OpenCL *)fem->data;
545:   if (!Ne) {
546:     PetscCall(PetscFEOpenCLLogResidual(fem, 0.0, 0.0));
547:     PetscFunctionReturn(PETSC_SUCCESS);
548:   }
549:   PetscCall(PetscFEGetSpatialDimension(fem, &dim));
550:   PetscCall(PetscFEGetQuadrature(fem, &q));
551:   PetscCall(PetscQuadratureGetData(q, NULL, &qNc, &N_q, &points, &weights));
552:   PetscCheck(qNc == 1, PETSC_COMM_SELF, PETSC_ERR_SUP, "Only supports scalar quadrature, not %" PetscInt_FMT " components", qNc);
553:   PetscCall(PetscFEGetDimension(fem, &N_b));
554:   PetscCall(PetscFEGetNumComponents(fem, &N_comp));
555:   PetscCall(PetscDSGetResidual(prob, field, &f0_func, &f1_func));
556:   PetscCall(PetscFEGetTileSizes(fem, NULL, &N_bl, &N_bc, &N_cb));
557:   N_bt  = N_b * N_comp;
558:   N_bst = N_bt * N_q;
559:   N_t   = N_bst * N_bl;
560:   PetscCheck(N_bc * N_comp == N_t, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Number of threads %d should be %d * %d", N_t, N_bc, N_comp);
561:   /* Calculate layout */
562:   if (Ne % (N_cb * N_bc)) { /* Remainder cells */
563:     PetscCall(PetscFEIntegrateResidual_Basic(prob, key, Ne, cgeom, coefficients, coefficients_t, probAux, coefficientsAux, t, elemVec));
564:     PetscFunctionReturn(PETSC_SUCCESS);
565:   }
566:   PetscCall(PetscFEOpenCLCalculateGrid(fem, Ne, N_cb * N_bc, &x, &y, &z));
567:   local_work_size[0]  = N_bc * N_comp;
568:   local_work_size[1]  = 1;
569:   local_work_size[2]  = 1;
570:   global_work_size[0] = x * local_work_size[0];
571:   global_work_size[1] = y * local_work_size[1];
572:   global_work_size[2] = z * local_work_size[2];
573:   PetscCall(PetscInfo(fem, "GPU layout grid(%zu,%zu,%zu) block(%zu,%zu,%zu) with %d batches\n", x, y, z, local_work_size[0], local_work_size[1], local_work_size[2], N_cb));
574:   PetscCall(PetscInfo(fem, " N_t: %d, N_cb: %d\n", N_t, N_cb));
575:   /* Generate code */
576:   if (probAux) {
577:     PetscSpace P;
578:     PetscInt   NfAux, order, f;

580:     PetscCall(PetscDSGetNumFields(probAux, &NfAux));
581:     for (f = 0; f < NfAux; ++f) {
582:       PetscFE feAux;

584:       PetscCall(PetscDSGetDiscretization(probAux, f, (PetscObject *)&feAux));
585:       PetscCall(PetscFEGetBasisSpace(feAux, &P));
586:       PetscCall(PetscSpaceGetDegree(P, &order, NULL));
587:       PetscCheck(order <= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Can only handle P0 coefficient fields");
588:     }
589:   }
590:   PetscCall(PetscFEOpenCLGetIntegrationKernel(fem, useAux, &ocl_prog, &ocl_kernel));
591:   /* Create buffers on the device and send data over */
592:   PetscCall(PetscDataTypeGetSize(ocl->realType, &realSize));
593:   PetscCheck(cgeom->numPoints <= 1, PETSC_COMM_SELF, PETSC_ERR_SUP, "Only support affine geometry for OpenCL integration right now");
594:   if (sizeof(PetscReal) != realSize) {
595:     switch (ocl->realType) {
596:     case PETSC_FLOAT: {
597:       PetscInt c, b, d;

599:       PetscCall(PetscMalloc4(Ne * N_bt, &f_coeff, Ne, &f_coeffAux, Ne * dim * dim, &f_invJ, Ne, &f_detJ));
600:       for (c = 0; c < Ne; ++c) {
601:         f_detJ[c] = (float)cgeom->detJ[c];
602:         for (d = 0; d < dim * dim; ++d) f_invJ[c * dim * dim + d] = (float)cgeom->invJ[c * dim * dim + d];
603:         for (b = 0; b < N_bt; ++b) f_coeff[c * N_bt + b] = (float)coefficients[c * N_bt + b];
604:       }
605:       if (coefficientsAux) { /* Assume P0 */
606:         for (c = 0; c < Ne; ++c) f_coeffAux[c] = (float)coefficientsAux[c];
607:       }
608:       oclCoeff = (void *)f_coeff;
609:       if (coefficientsAux) {
610:         oclCoeffAux = (void *)f_coeffAux;
611:       } else {
612:         oclCoeffAux = NULL;
613:       }
614:       oclInvJ = (void *)f_invJ;
615:       oclDetJ = (void *)f_detJ;
616:     } break;
617:     case PETSC_DOUBLE: {
618:       PetscInt c, b, d;

620:       PetscCall(PetscMalloc4(Ne * N_bt, &d_coeff, Ne, &d_coeffAux, Ne * dim * dim, &d_invJ, Ne, &d_detJ));
621:       for (c = 0; c < Ne; ++c) {
622:         d_detJ[c] = (double)cgeom->detJ[c];
623:         for (d = 0; d < dim * dim; ++d) d_invJ[c * dim * dim + d] = (double)cgeom->invJ[c * dim * dim + d];
624:         for (b = 0; b < N_bt; ++b) d_coeff[c * N_bt + b] = (double)coefficients[c * N_bt + b];
625:       }
626:       if (coefficientsAux) { /* Assume P0 */
627:         for (c = 0; c < Ne; ++c) d_coeffAux[c] = (double)coefficientsAux[c];
628:       }
629:       oclCoeff = (void *)d_coeff;
630:       if (coefficientsAux) {
631:         oclCoeffAux = (void *)d_coeffAux;
632:       } else {
633:         oclCoeffAux = NULL;
634:       }
635:       oclInvJ = (void *)d_invJ;
636:       oclDetJ = (void *)d_detJ;
637:     } break;
638:     default:
639:       SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Unsupported PETSc type %d", ocl->realType);
640:     }
641:   } else {
642:     PetscInt c, d;

644:     PetscCall(PetscMalloc2(Ne * dim * dim, &r_invJ, Ne, &r_detJ));
645:     for (c = 0; c < Ne; ++c) {
646:       r_detJ[c] = cgeom->detJ[c];
647:       for (d = 0; d < dim * dim; ++d) r_invJ[c * dim * dim + d] = cgeom->invJ[c * dim * dim + d];
648:     }
649:     oclCoeff    = (void *)coefficients;
650:     oclCoeffAux = (void *)coefficientsAux;
651:     oclInvJ     = (void *)r_invJ;
652:     oclDetJ     = (void *)r_detJ;
653:   }
654:   o_coefficients = clCreateBuffer(ocl->ctx_id, CL_MEM_READ_ONLY | CL_MEM_COPY_HOST_PTR, Ne * N_bt * realSize, oclCoeff, &err);
655:   if (coefficientsAux) {
656:     o_coefficientsAux = clCreateBuffer(ocl->ctx_id, CL_MEM_READ_ONLY | CL_MEM_COPY_HOST_PTR, Ne * realSize, oclCoeffAux, &err);
657:   } else {
658:     o_coefficientsAux = clCreateBuffer(ocl->ctx_id, CL_MEM_READ_ONLY, Ne * realSize, oclCoeffAux, &err);
659:   }
660:   o_jacobianInverses     = clCreateBuffer(ocl->ctx_id, CL_MEM_READ_ONLY | CL_MEM_COPY_HOST_PTR, Ne * dim * dim * realSize, oclInvJ, &err);
661:   o_jacobianDeterminants = clCreateBuffer(ocl->ctx_id, CL_MEM_READ_ONLY | CL_MEM_COPY_HOST_PTR, Ne * realSize, oclDetJ, &err);
662:   o_elemVec              = clCreateBuffer(ocl->ctx_id, CL_MEM_WRITE_ONLY, Ne * N_bt * realSize, NULL, &err);
663:   /* Kernel launch */
664:   PetscCall(clSetKernelArg(ocl_kernel, 0, sizeof(cl_int), (void *)&N_cb));
665:   PetscCall(clSetKernelArg(ocl_kernel, 1, sizeof(cl_mem), (void *)&o_coefficients));
666:   PetscCall(clSetKernelArg(ocl_kernel, 2, sizeof(cl_mem), (void *)&o_coefficientsAux));
667:   PetscCall(clSetKernelArg(ocl_kernel, 3, sizeof(cl_mem), (void *)&o_jacobianInverses));
668:   PetscCall(clSetKernelArg(ocl_kernel, 4, sizeof(cl_mem), (void *)&o_jacobianDeterminants));
669:   PetscCall(clSetKernelArg(ocl_kernel, 5, sizeof(cl_mem), (void *)&o_elemVec));
670:   PetscCall(clEnqueueNDRangeKernel(ocl->queue_id, ocl_kernel, 3, NULL, global_work_size, local_work_size, 0, NULL, &ocl_ev));
671:   /* Read data back from device */
672:   if (sizeof(PetscReal) != realSize) {
673:     switch (ocl->realType) {
674:     case PETSC_FLOAT: {
675:       float   *elem;
676:       PetscInt c, b;

678:       PetscCall(PetscFree4(f_coeff, f_coeffAux, f_invJ, f_detJ));
679:       PetscCall(PetscMalloc1(Ne * N_bt, &elem));
680:       PetscCall(clEnqueueReadBuffer(ocl->queue_id, o_elemVec, CL_TRUE, 0, Ne * N_bt * realSize, elem, 0, NULL, NULL));
681:       for (c = 0; c < Ne; ++c) {
682:         for (b = 0; b < N_bt; ++b) elemVec[c * N_bt + b] = (PetscScalar)elem[c * N_bt + b];
683:       }
684:       PetscCall(PetscFree(elem));
685:     } break;
686:     case PETSC_DOUBLE: {
687:       double  *elem;
688:       PetscInt c, b;

690:       PetscCall(PetscFree4(d_coeff, d_coeffAux, d_invJ, d_detJ));
691:       PetscCall(PetscMalloc1(Ne * N_bt, &elem));
692:       PetscCall(clEnqueueReadBuffer(ocl->queue_id, o_elemVec, CL_TRUE, 0, Ne * N_bt * realSize, elem, 0, NULL, NULL));
693:       for (c = 0; c < Ne; ++c) {
694:         for (b = 0; b < N_bt; ++b) elemVec[c * N_bt + b] = (PetscScalar)elem[c * N_bt + b];
695:       }
696:       PetscCall(PetscFree(elem));
697:     } break;
698:     default:
699:       SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Unsupported PETSc type %d", ocl->realType);
700:     }
701:   } else {
702:     PetscCall(PetscFree2(r_invJ, r_detJ));
703:     PetscCall(clEnqueueReadBuffer(ocl->queue_id, o_elemVec, CL_TRUE, 0, Ne * N_bt * realSize, elemVec, 0, NULL, NULL));
704:   }
705:   /* Log performance */
706:   PetscCall(clGetEventProfilingInfo(ocl_ev, CL_PROFILING_COMMAND_START, sizeof(cl_ulong), &ns_start, NULL));
707:   PetscCall(clGetEventProfilingInfo(ocl_ev, CL_PROFILING_COMMAND_END, sizeof(cl_ulong), &ns_end, NULL));
708:   f0Flops = 0;
709:   switch (ocl->op) {
710:   case LAPLACIAN:
711:     f1Flops = useAux ? dim : 0;
712:     break;
713:   case ELASTICITY:
714:     f1Flops = 2 * dim * dim;
715:     break;
716:   }
717:   numFlops = Ne * (N_q * (N_b * N_comp * ((useField ? 2 : 0) + (useFieldDer ? 2 * dim * (dim + 1) : 0))
718:                           /*+
719:        N_ba*N_compa*((useFieldAux ? 2 : 0) + (useFieldDerAux ? 2*dim*(dim + 1) : 0))*/
720:                           + N_comp * ((useF0 ? f0Flops + 2 : 0) + (useF1 ? f1Flops + 2 * dim : 0))) +
721:                    N_b * ((useF0 ? 2 : 0) + (useF1 ? 2 * dim * (dim + 1) : 0)));
722:   PetscCall(PetscFEOpenCLLogResidual(fem, (ns_end - ns_start) * 1.0e-9, numFlops));
723:   /* Cleanup */
724:   PetscCall(clReleaseMemObject(o_coefficients));
725:   PetscCall(clReleaseMemObject(o_coefficientsAux));
726:   PetscCall(clReleaseMemObject(o_jacobianInverses));
727:   PetscCall(clReleaseMemObject(o_jacobianDeterminants));
728:   PetscCall(clReleaseMemObject(o_elemVec));
729:   PetscCall(clReleaseKernel(ocl_kernel));
730:   PetscCall(clReleaseProgram(ocl_prog));
731:   PetscFunctionReturn(PETSC_SUCCESS);
732: }

734: PETSC_INTERN PetscErrorCode PetscFESetUp_Basic(PetscFE);
735: PETSC_INTERN PetscErrorCode PetscFECreateTabulation_Basic(PetscFE, PetscInt, const PetscReal[], PetscInt, PetscTabulation);

737: static PetscErrorCode PetscFEInitialize_OpenCL(PetscFE fem)
738: {
739:   PetscFunctionBegin;
740:   fem->ops->setfromoptions          = NULL;
741:   fem->ops->setup                   = PetscFESetUp_Basic;
742:   fem->ops->view                    = NULL;
743:   fem->ops->destroy                 = PetscFEDestroy_OpenCL;
744:   fem->ops->getdimension            = PetscFEGetDimension_Basic;
745:   fem->ops->createtabulation        = PetscFECreateTabulation_Basic;
746:   fem->ops->integrateresidual       = PetscFEIntegrateResidual_OpenCL;
747:   fem->ops->integratebdresidual     = NULL /* PetscFEIntegrateBdResidual_OpenCL */;
748:   fem->ops->integratejacobianaction = NULL /* PetscFEIntegrateJacobianAction_OpenCL */;
749:   fem->ops->integratejacobian       = PetscFEIntegrateJacobian_Basic;
750:   PetscFunctionReturn(PETSC_SUCCESS);
751: }

753: /*MC
754:   PETSCFEOPENCL = "opencl" - A `PetscFEType` that integrates using a vectorized OpenCL implementation

756:   Level: intermediate

758: .seealso: `PetscFEType`, `PetscFECreate()`, `PetscFESetType()`
759: M*/

761: PETSC_EXTERN PetscErrorCode PetscFECreate_OpenCL(PetscFE fem)
762: {
763:   PetscFE_OpenCL *ocl;
764:   cl_uint         num_platforms;
765:   cl_platform_id  platform_ids[42];
766:   cl_uint         num_devices;
767:   cl_device_id    device_ids[42];
768:   cl_int          err;

770:   PetscFunctionBegin;
772:   PetscCall(PetscNew(&ocl));
773:   fem->data = ocl;

775:   /* Init Platform */
776:   PetscCall(clGetPlatformIDs(42, platform_ids, &num_platforms));
777:   PetscCheck(num_platforms, PetscObjectComm((PetscObject)fem), PETSC_ERR_SUP, "No OpenCL platform found.");
778:   ocl->pf_id = platform_ids[0];
779:   /* Init Device */
780:   PetscCall(clGetDeviceIDs(ocl->pf_id, CL_DEVICE_TYPE_ALL, 42, device_ids, &num_devices));
781:   PetscCheck(num_devices, PetscObjectComm((PetscObject)fem), PETSC_ERR_SUP, "No OpenCL device found.");
782:   ocl->dev_id = device_ids[0];
783:   /* Create context with one command queue */
784:   ocl->ctx_id = clCreateContext(0, 1, &(ocl->dev_id), NULL, NULL, &err);
785:   PetscCall(err);
786:   ocl->queue_id = clCreateCommandQueue(ocl->ctx_id, ocl->dev_id, CL_QUEUE_PROFILING_ENABLE, &err);
787:   PetscCall(err);
788:   /* Types */
789:   ocl->realType = PETSC_FLOAT;
790:   /* Register events */
791:   PetscCall(PetscLogEventRegister("OpenCL FEResidual", PETSCFE_CLASSID, &ocl->residualEvent));
792:   /* Equation handling */
793:   ocl->op = LAPLACIAN;

795:   PetscCall(PetscFEInitialize_OpenCL(fem));
796:   PetscFunctionReturn(PETSC_SUCCESS);
797: }

799: /*@
800:   PetscFEOpenCLSetRealType - Set the scalar type for running on the OpenCL accelerator

802:   Input Parameters:
803: + fem      - The `PetscFE`
804: - realType - The scalar type

806:   Level: developer

808: .seealso: `PetscFE`, `PetscFEOpenCLGetRealType()`
809: @*/
810: PetscErrorCode PetscFEOpenCLSetRealType(PetscFE fem, PetscDataType realType)
811: {
812:   PetscFE_OpenCL *ocl = (PetscFE_OpenCL *)fem->data;

814:   PetscFunctionBegin;
816:   ocl->realType = realType;
817:   PetscFunctionReturn(PETSC_SUCCESS);
818: }

820: /*@
821:   PetscFEOpenCLGetRealType - Get the scalar type for running on the OpenCL accelerator

823:   Input Parameter:
824: . fem - The `PetscFE`

826:   Output Parameter:
827: . realType - The scalar type

829:   Level: developer

831: .seealso: `PetscFE`, `PetscFEOpenCLSetRealType()`
832: @*/
833: PetscErrorCode PetscFEOpenCLGetRealType(PetscFE fem, PetscDataType *realType)
834: {
835:   PetscFE_OpenCL *ocl = (PetscFE_OpenCL *)fem->data;

837:   PetscFunctionBegin;
840:   *realType = ocl->realType;
841:   PetscFunctionReturn(PETSC_SUCCESS);
842: }

844: #endif /* PETSC_HAVE_OPENCL */