xref: /petsc/src/ksp/pc/impls/bjacobi/bjkokkos/bjkokkos.kokkos.cxx (revision fdf6c4e30aafdbc795e4f76379caa977fd5cdf5a)
1 #include <petscvec_kokkos.hpp>
2 #include <petsc/private/pcimpl.h>
3 #include <petsc/private/kspimpl.h>
4 #include <petscksp.h>            /*I "petscksp.h" I*/
5 #include "petscsection.h"
6 #include <petscdmcomposite.h>
7 #include "Kokkos_Core.hpp"
8 
9 #include <../src/mat/impls/aij/seq/aij.h>
10 #include <../src/mat/impls/aij/seq/kokkos/aijkok.hpp>
11 
12 #if defined(PETSC_HAVE_CUDA_NVTX)
13 #include <nvToolsExt.h>
14 #endif
15 
16 #define PCBJKOKKOS_SHARED_LEVEL 0  // 0 is shared, 1 is global
17 #define PCBJKOKKOS_VEC_SIZE 16
18 #define PCBJKOKKOS_TEAM_SIZE 16
19 
20 #define PCBJKOKKOS_VERBOSE_LEVEL 2
21 
22 typedef Kokkos::DefaultExecutionSpace exec_space;
23 using layout = Kokkos::LayoutRight;
24 using IntView            = Kokkos::View<PetscInt**, layout, exec_space>;
25 using AMatrixValueView   = const Kokkos::View<PetscScalar **, layout, exec_space>;
26 using XYType             = const Kokkos::View<PetscScalar **, layout, exec_space>;
27 
28 typedef enum {BATCH_KSP_BICG_IDX,BATCH_KSP_TFQMR_IDX,BATCH_KSP_GMRES_IDX,NUM_BATCH_TYPES} KSPIndex;
29 typedef struct {
30   Vec                                              vec_diag;
31   PetscInt                                         nBlocks; /* total number of blocks */
32   PetscInt                                         n; // cache host version of d_bid_eqOffset_k[nBlocks]
33   KSP                                              ksp; // Used just for options. Should have one for each block
34   Kokkos::View<PetscInt*, Kokkos::LayoutRight>     *d_bid_eqOffset_k;
35   Kokkos::View<PetscScalar*, Kokkos::LayoutRight>  *d_idiag_k;
36   Kokkos::View<PetscInt*>                          *d_isrow_k;
37   Kokkos::View<PetscInt*>                          *d_isicol_k;
38   KSPIndex                                         ksp_type_idx;
39   PetscInt                                         nwork;
40   PetscInt                                         const_block_size; // used to decide to use shared memory for work vectors
41   PetscInt                                         *dm_Nf;  // Number of fields in each DM
42   PetscInt                                         num_dms;
43   // diagnostics
44   PetscBool                                        reason;
45   PetscBool                                        monitor;
46   PetscInt                                         batch_target;
47   PetscInt                                         nsolves_team;
48   PetscInt                                         max_nits;
49   // caches
50   IntView                                          *rowOffsets;
51   IntView                                          *colIndices;
52   XYType                                           *batch_b;
53   XYType                                           *batch_x;
54   AMatrixValueView                                 *batch_values;
55 } PC_PCBJKOKKOS;
56 
57 #if defined(PETSC_HAVE_KOKKOS_KERNELS_GMRES)
58 #include <fstream>
59 
60 #include "Kokkos_Timer.hpp"
61 #include "Kokkos_Random.hpp"
62 #include "Kokkos_UnorderedMap.hpp"
63 #include "Kokkos_Sort.hpp"
64 
65 /// KokkosKernels headers
66 #include "KokkosBatched_Util.hpp"
67 #include "KokkosBatched_Vector.hpp"
68 
69 #include <Kokkos_ArithTraits.hpp>
70 #include <KokkosBatched_Util.hpp>
71 #include <KokkosBatched_Vector.hpp>
72 #include <KokkosBatched_Copy_Decl.hpp>
73 #include <KokkosBatched_Copy_Impl.hpp>
74 #include <KokkosBatched_AddRadial_Decl.hpp>
75 #include <KokkosBatched_AddRadial_Impl.hpp>
76 #include <KokkosBatched_Gemm_Decl.hpp>
77 #include <KokkosBatched_Gemm_Serial_Impl.hpp>
78 #include <KokkosBatched_Gemm_Team_Impl.hpp>
79 #include <KokkosBatched_Gemv_Decl.hpp>
80 #include <KokkosBatched_Gemv_Serial_Impl.hpp>
81 #include <KokkosBatched_Gemv_Team_Impl.hpp>
82 #include <KokkosBatched_Trsm_Decl.hpp>
83 #include <KokkosBatched_Trsm_Serial_Impl.hpp>
84 #include <KokkosBatched_Trsm_Team_Impl.hpp>
85 #include <KokkosBatched_Trsv_Decl.hpp>
86 #include <KokkosBatched_Trsv_Serial_Impl.hpp>
87 #include <KokkosBatched_Trsv_Team_Impl.hpp>
88 #include <KokkosBatched_LU_Decl.hpp>
89 #include <KokkosBatched_LU_Serial_Impl.hpp>
90 #include <KokkosBatched_LU_Team_Impl.hpp>
91 #include <KokkosSparse_CrsMatrix.hpp>
92 #include "KokkosBatched_Spmv.hpp"
93 #include "KokkosBatched_CrsMatrix.hpp"
94 #include "KokkosBatched_Krylov_Handle.hpp"
95 #include "KokkosBatched_GMRES.hpp"
96 #include "KokkosBatched_JacobiPrec.hpp"
97 
98 template <typename DeviceType, typename ValuesViewType, typename IntView,
99           typename VectorViewType, typename KrylovHandleType>
100 struct Functor_TestBatchedTeamVectorGMRES {
101   const ValuesViewType _D;
102   const ValuesViewType _diag;
103   const IntView _r;
104   const IntView _c;
105   const VectorViewType _X;
106   const VectorViewType _B;
107   const int _N_team, _team_size, _vector_length;
108   const int _N_iteration;
109   const double _tol;
110   const int _ortho_strategy;
111   const int _scratch_pad_level;
112   KrylovHandleType _handle;
113 
114   KOKKOS_INLINE_FUNCTION
115   Functor_TestBatchedTeamVectorGMRES(const ValuesViewType &D, const IntView &r,
116                                   const IntView &c, const VectorViewType &X,
117                                   const VectorViewType &B, const int N_team,
118                                   const int team_size, const int vector_length,
119                                   const int N_iteration, const double tol,
120                                   const int ortho_strategy,
121                                   const int scratch_pad_level, KrylovHandleType &handle)
122       : _D(D), _r(r), _c(c), _X(X), _B(B), _N_team(N_team), _team_size(team_size), _vector_length(vector_length),
123       _N_iteration(N_iteration), _tol(tol), _ortho_strategy(ortho_strategy), _scratch_pad_level(scratch_pad_level),
124       _handle(handle) {
125   }
126 
127   KOKKOS_INLINE_FUNCTION
128   Functor_TestBatchedTeamVectorGMRES(const ValuesViewType &D, const ValuesViewType &diag, const IntView &r,
129                                   const IntView &c, const VectorViewType &X,
130                                   const VectorViewType &B, const int N_team,
131                                   const int team_size, const int vector_length,
132                                   const int N_iteration, const double tol,
133                                   int ortho_strategy,
134                                   const int scratch_pad_level, KrylovHandleType &handle)
135       : _D(D), _diag(diag), _r(r), _c(c), _X(X), _B(B), _N_team(N_team), _team_size(team_size), _vector_length(vector_length),
136       _N_iteration(N_iteration), _tol(tol), _ortho_strategy(ortho_strategy), _scratch_pad_level(scratch_pad_level),
137       _handle(handle) {
138   }
139 
140   template <typename MemberType>
141   KOKKOS_INLINE_FUNCTION void operator()(const MemberType &member) const {
142     const int first_matrix = static_cast<int>(member.league_rank()) * _N_team;
143     const int N            = _D.extent(0);
144     const int last_matrix =
145         (static_cast<int>(member.league_rank() + 1) * _N_team < N
146              ? static_cast<int>(member.league_rank() + 1) * _N_team
147              : N);
148     const int graphID = static_cast<int>(member.league_rank());
149     using TeamVectorCopy1D = KokkosBatched::TeamVectorCopy<MemberType, KokkosBatched::Trans::NoTranspose, 1>;
150 
151     auto d = Kokkos::subview(_D, Kokkos::make_pair(first_matrix, last_matrix),
152                              Kokkos::ALL);
153     auto x = Kokkos::subview(_X, Kokkos::make_pair(first_matrix, last_matrix),
154                              Kokkos::ALL);
155     auto b = Kokkos::subview(_B, Kokkos::make_pair(first_matrix, last_matrix),
156                              Kokkos::ALL);
157     using ScratchPadIntViewType = Kokkos::View<
158         typename IntView::non_const_value_type*,
159         typename IntView::array_layout,
160         typename IntView::execution_space::scratch_memory_space>;
161     using ScratchPadValuesViewType = Kokkos::View<
162         typename ValuesViewType::non_const_value_type**,
163         typename ValuesViewType::array_layout,
164         typename ValuesViewType::execution_space::scratch_memory_space>;
165 
166     using Operator = KokkosBatched::CrsMatrix<ValuesViewType, ScratchPadIntViewType>;
167     ScratchPadIntViewType r(member.team_scratch(1), _r.extent(1));
168     ScratchPadIntViewType c(member.team_scratch(1), _c.extent(1));
169 
170     TeamVectorCopy1D::invoke(member, Kokkos::subview(_r,graphID, Kokkos::ALL), r);
171     TeamVectorCopy1D::invoke(member, Kokkos::subview(_c,graphID, Kokkos::ALL), c);
172     Operator A(d, r, c);
173 
174     ScratchPadValuesViewType diag(member.team_scratch(1), last_matrix-first_matrix, _diag.extent(1));
175     using PrecOperator = KokkosBatched::JacobiPrec<ScratchPadValuesViewType>;
176 
177     KokkosBatched::TeamVectorCopy<MemberType>::invoke(member, Kokkos::subview(_diag, Kokkos::make_pair(first_matrix, last_matrix), Kokkos::ALL), diag);
178     PrecOperator P(diag);
179     P.setComputedInverse();
180 
181     KokkosBatched::TeamVectorGMRES<MemberType>::template invoke<Operator, VectorViewType, PrecOperator, KrylovHandleType>(member, A, b, x, P, _handle);
182   }
183   inline double run(PC pc)
184   {
185     typedef typename ValuesViewType::value_type value_type;
186     std::string name("KokkosBatched::Test::TeamVectorGMRES");
187     Kokkos::Timer timer;
188     Kokkos::Profiling::pushRegion(name.c_str());
189 
190     Kokkos::TeamPolicy<DeviceType> auto_policy(ceil(1.*_D.extent(0) / _N_team), Kokkos::AUTO(), Kokkos::AUTO());
191     Kokkos::TeamPolicy<DeviceType> tuned_policy(ceil(1.*_D.extent(0) / _N_team), _team_size, _vector_length);
192     Kokkos::TeamPolicy<DeviceType> policy;
193 
194     if (_team_size < 1)
195       policy = auto_policy;
196     else
197       policy = tuned_policy;
198 
199     _handle.set_max_iteration(_N_iteration);
200     _handle.set_tolerance(_tol);
201     _handle.set_ortho_strategy(_ortho_strategy);
202     _handle.set_scratch_pad_level(_scratch_pad_level);
203     _handle.set_compute_last_residual(true);
204 
205     int maximum_iteration = _handle.get_max_iteration();
206 
207     using ScalarType = typename ValuesViewType::non_const_value_type;
208     using Layout     = typename ValuesViewType::array_layout;
209     using EXSP       = typename ValuesViewType::execution_space;
210 
211     using MagnitudeType =
212           typename Kokkos::Details::ArithTraits<ScalarType>::mag_type;
213 
214     using ViewType1D = Kokkos::View<MagnitudeType *, Layout, EXSP>;
215     using ViewType2D = Kokkos::View<ScalarType **, Layout, EXSP>;
216     using ViewType3D = Kokkos::View<ScalarType ***, Layout, EXSP>;
217     using IntViewType1D = Kokkos::View<PetscInt *, Layout, EXSP>;
218 
219     size_t bytes_1D = ViewType2D::shmem_size(_N_team, 1);
220     size_t bytes_row_ptr = IntViewType1D::shmem_size(_r.extent(1));
221     size_t bytes_col_idc = IntViewType1D::shmem_size(_c.extent(1));
222     size_t bytes_2D_1 = ViewType2D::shmem_size(_N_team, _X.extent(1));
223     size_t bytes_2D_2 = ViewType2D::shmem_size(_N_team, maximum_iteration+1);
224 
225     size_t bytes_diag = bytes_2D_1;
226     size_t bytes_tmp = 2 * bytes_2D_1 + 2 * bytes_1D + bytes_2D_2;
227 
228     policy.set_scratch_size(0, Kokkos::PerTeam(bytes_tmp));
229     policy.set_scratch_size(1, Kokkos::PerTeam(bytes_col_idc + bytes_row_ptr + bytes_diag));
230     PetscInfo(pc,"%d scratch memory(0) = %d + %d + %d bytes_diag=%d; %d scratch memory(1); %d maximum_iterations\n",
231               (int)(bytes_tmp), 2 * (int)bytes_2D_1, 2 * (int)bytes_1D, (int)bytes_2D_2, (int)bytes_diag, (int)(bytes_row_ptr+bytes_col_idc+bytes_diag), (int)maximum_iteration);
232     exec_space().fence();
233     timer.reset();
234     Kokkos::parallel_for(name.c_str(), policy, *this);
235     exec_space().fence();
236     double sec = timer.seconds();
237 
238     return sec;
239   }
240 };
241 #endif  // KK GMRES
242 
243 typedef Kokkos::TeamPolicy<>::member_type team_member;
244 
245 static PetscErrorCode  PCBJKOKKOSCreateKSP_BJKOKKOS(PC pc)
246 {
247   const char    *prefix;
248   PC_PCBJKOKKOS *jac = (PC_PCBJKOKKOS*)pc->data;
249   DM             dm;
250 
251   PetscFunctionBegin;
252   PetscCall(KSPCreate(PetscObjectComm((PetscObject)pc),&jac->ksp));
253   PetscCall(KSPSetErrorIfNotConverged(jac->ksp,pc->erroriffailure));
254   PetscCall(PetscObjectIncrementTabLevel((PetscObject)jac->ksp,(PetscObject)pc,1));
255   PetscCall(PCGetOptionsPrefix(pc,&prefix));
256   PetscCall(KSPSetOptionsPrefix(jac->ksp,prefix));
257   PetscCall(KSPAppendOptionsPrefix(jac->ksp,"pc_bjkokkos_"));
258   PetscCall(PCGetDM(pc,&dm));
259   if (dm) {
260     PetscCall(KSPSetDM(jac->ksp, dm));
261     PetscCall(KSPSetDMActive(jac->ksp, PETSC_FALSE));
262   }
263   jac->reason       = PETSC_FALSE;
264   jac->monitor      = PETSC_FALSE;
265   jac->batch_target = -1;
266   jac->nsolves_team = 1;
267   jac->ksp->max_it = 50; // this is realy for GMRES w/o restarts
268   PetscFunctionReturn(0);
269 }
270 
271 // y <-- Ax
272 KOKKOS_INLINE_FUNCTION PetscErrorCode MatMult(const team_member team,  const PetscInt *glb_Aai, const PetscInt *glb_Aaj, const PetscScalar *glb_Aaa, const PetscInt *r, const PetscInt *ic, const PetscInt start, const PetscInt end, const PetscScalar *x_loc, PetscScalar *y_loc)
273 {
274   Kokkos::parallel_for(Kokkos::TeamThreadRange(team,start,end), [=] (const int rowb) {
275       int rowa = ic[rowb];
276       int n = glb_Aai[rowa+1] - glb_Aai[rowa];
277       const PetscInt    *aj  = glb_Aaj + glb_Aai[rowa];
278       const PetscScalar *aa  = glb_Aaa + glb_Aai[rowa];
279       PetscScalar sum;
280       Kokkos::parallel_reduce(Kokkos::ThreadVectorRange (team, n), [=] (const int i, PetscScalar& lsum) {
281           lsum += aa[i] * x_loc[r[aj[i]]-start];
282         }, sum);
283       Kokkos::single(Kokkos::PerThread (team),[=]() {y_loc[rowb-start] = sum;});
284     });
285   team.team_barrier();
286   return 0;
287 }
288 
289 // temp buffer per thread with reduction at end?
290 KOKKOS_INLINE_FUNCTION PetscErrorCode MatMultTranspose(const team_member team, const PetscInt *glb_Aai, const PetscInt *glb_Aaj, const PetscScalar *glb_Aaa, const PetscInt *r, const PetscInt *ic, const PetscInt start, const PetscInt end, const PetscScalar *x_loc, PetscScalar *y_loc)
291 {
292   Kokkos::parallel_for(Kokkos::TeamVectorRange(team,end-start), [=] (int i) { y_loc[i] = 0;});
293   team.team_barrier();
294   Kokkos::parallel_for(Kokkos::TeamThreadRange(team,start,end), [=] (const int rowb) {
295       int rowa = ic[rowb];
296       int n = glb_Aai[rowa+1] - glb_Aai[rowa];
297       const PetscInt    *aj  = glb_Aaj + glb_Aai[rowa];
298       const PetscScalar *aa  = glb_Aaa + glb_Aai[rowa];
299       const PetscScalar xx = x_loc[rowb-start]; // rowb = ic[rowa] = ic[r[rowb]]
300       Kokkos::parallel_for(Kokkos::ThreadVectorRange(team,n), [=] (const int &i) {
301           PetscScalar val = aa[i] * xx;
302           Kokkos::atomic_fetch_add(&y_loc[r[aj[i]]-start], val);
303         });
304     });
305   team.team_barrier();
306   return 0;
307 }
308 
309 typedef struct Batch_MetaData_TAG
310 {
311   PetscInt           flops;
312   PetscInt           its;
313   KSPConvergedReason reason;
314 }Batch_MetaData;
315 
316 // Solve A(BB^-1)x = y with TFQMR. Right preconditioned to get un-preconditioned residual
317 KOKKOS_INLINE_FUNCTION PetscErrorCode BJSolve_TFQMR(const team_member team, const PetscInt *glb_Aai, const PetscInt *glb_Aaj, const PetscScalar *glb_Aaa, const PetscInt *r, const PetscInt *ic, PetscScalar *work_space_global, const int stride_global,  const int nShareVec, PetscScalar *work_space_shared, const int stride_shared, PetscReal rtol, PetscReal atol, PetscReal dtol,PetscInt maxit, Batch_MetaData *metad, const PetscInt start, const PetscInt end, const PetscScalar glb_idiag[], const PetscScalar *glb_b, PetscScalar *glb_x, bool monitor)
318 {
319   using Kokkos::parallel_reduce;
320   using Kokkos::parallel_for;
321   int               Nblk = end-start, i,m, stride = stride_shared, idx=0;
322   PetscReal         dp,dpold,w,dpest,tau,psi,cm,r0;
323   const PetscScalar *Diag = &glb_idiag[start];
324   PetscScalar       *ptr = work_space_shared, rho,rhoold,a,s,b,eta,etaold,psiold,cf,dpi;
325 
326   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
327   PetscScalar       *XX = ptr; ptr += stride;
328   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
329   PetscScalar       *R = ptr; ptr += stride;
330   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
331   PetscScalar       *RP = ptr; ptr += stride;
332   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
333   PetscScalar       *V = ptr; ptr += stride;
334   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
335   PetscScalar       *T = ptr; ptr += stride;
336   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
337   PetscScalar       *Q = ptr; ptr += stride;
338   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
339   PetscScalar       *P = ptr; ptr += stride;
340   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
341   PetscScalar       *U = ptr; ptr += stride;
342   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
343   PetscScalar       *D = ptr; ptr += stride;
344   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
345   PetscScalar       *AUQ = V;
346 
347   // init: get b, zero x
348   parallel_for(Kokkos::TeamVectorRange(team, start, end), [=] (int rowb) {
349       int rowa = ic[rowb];
350       R[rowb-start] = glb_b[rowa];
351       XX[rowb-start] = 0;
352     });
353   team.team_barrier();
354   parallel_reduce(Kokkos::TeamVectorRange (team, Nblk), [=] (const int idx, PetscScalar& lsum) {lsum += R[idx]*PetscConj(R[idx]);}, dpi);
355   team.team_barrier();
356   r0 = dp = PetscSqrtReal(PetscRealPart(dpi));
357   // diagnostics
358 #if defined(PETSC_USE_DEBUG) && !defined(PETSC_HAVE_SYCL)
359   if (monitor) Kokkos::single (Kokkos::PerTeam (team), [=] () { printf("%3d KSP Residual norm %14.12e \n", 0, (double)dp);});
360 #endif
361   if (dp < atol) {metad->reason = KSP_CONVERGED_ATOL_NORMAL; return 0;}
362   if (0 == maxit) {metad->reason = KSP_DIVERGED_ITS; return 0;}
363 
364   /* Make the initial Rp = R */
365   parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {RP[idx] = R[idx];});
366   team.team_barrier();
367   /* Set the initial conditions */
368   etaold = 0.0;
369   psiold = 0.0;
370   tau    = dp;
371   dpold  = dp;
372 
373   /* rhoold = (r,rp)     */
374   parallel_reduce(Kokkos::TeamVectorRange (team, Nblk), [=] (const int idx, PetscScalar& dot) {dot += R[idx]*PetscConj(RP[idx]);}, rhoold);
375   team.team_barrier();
376   parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {U[idx] = R[idx]; P[idx] = R[idx]; T[idx] = Diag[idx]*P[idx]; D[idx] = 0;});
377   team.team_barrier();
378   MatMult         (team,glb_Aai,glb_Aaj,glb_Aaa,r,ic,start,end,T,V);
379 
380   i=0;
381   do {
382     /* s <- (v,rp)          */
383     parallel_reduce(Kokkos::TeamVectorRange (team, Nblk), [=] (const int idx, PetscScalar& dot) {dot += V[idx]*PetscConj(RP[idx]);}, s);
384     team.team_barrier();
385     a    = rhoold / s;                              /* a <- rho / s         */
386     /* q <- u - a v    VecWAXPY(w,alpha,x,y): w = alpha x + y.     */
387     /* t <- u + q           */
388     parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {Q[idx] = U[idx] - a*V[idx]; T[idx] = U[idx] + Q[idx];});
389     team.team_barrier();
390     // KSP_PCApplyBAorAB
391     parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {T[idx] = Diag[idx]*T[idx]; });
392     team.team_barrier();
393     MatMult         (team,glb_Aai,glb_Aaj,glb_Aaa,r,ic,start,end,T,AUQ);
394     /* r <- r - a K (u + q) */
395     parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {R[idx] = R[idx] - a*AUQ[idx]; });
396     team.team_barrier();
397     parallel_reduce(Kokkos::TeamVectorRange (team, Nblk), [=] (const int idx, PetscScalar& lsum) {lsum += R[idx]*PetscConj(R[idx]);}, dpi);
398     team.team_barrier();
399     dp = PetscSqrtReal(PetscRealPart(dpi));
400     for (m=0; m<2; m++) {
401       if (!m) w = PetscSqrtReal(dp*dpold);
402       else w = dp;
403       psi = w / tau;
404       cm  = 1.0 / PetscSqrtReal(1.0 + psi * psi);
405       tau = tau * psi * cm;
406       eta = cm * cm * a;
407       cf  = psiold * psiold * etaold / a;
408       if (!m) {
409         /* D = U + cf D */
410         parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {D[idx] = U[idx] + cf*D[idx]; });
411       } else {
412         /* D = Q + cf D */
413         parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {D[idx] = Q[idx] + cf*D[idx]; });
414       }
415       team.team_barrier();
416       parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {XX[idx] = XX[idx] + eta*D[idx]; });
417       team.team_barrier();
418       dpest = PetscSqrtReal(2*i + m + 2.0) * tau;
419 #if defined(PETSC_USE_DEBUG) && !defined(PETSC_HAVE_SYCL)
420       if (monitor && m==1) Kokkos::single (Kokkos::PerTeam (team), [=] () { printf("%3d KSP Residual norm %14.12e \n", i+1, (double)dpest);});
421 #endif
422       if (dpest < atol) {metad->reason = KSP_CONVERGED_ATOL_NORMAL; goto done;}
423       if (dpest/r0 < rtol) {metad->reason = KSP_CONVERGED_RTOL_NORMAL; goto done;}
424 #if defined(PETSC_USE_DEBUG) && !defined(PETSC_HAVE_SYCL)
425       if (dpest/r0 > dtol) {metad->reason = KSP_DIVERGED_DTOL; Kokkos::single (Kokkos::PerTeam (team), [=] () {printf("ERROR block %d diverged: %d it, res=%e, r_0=%e\n",team.league_rank(),i,dpest,r0);}); goto done;}
426 #else
427       if (dpest/r0 > dtol) {metad->reason = KSP_DIVERGED_DTOL; goto done;}
428 #endif
429       if (i+1 == maxit) {metad->reason = KSP_DIVERGED_ITS; goto done;}
430 
431       etaold = eta;
432       psiold = psi;
433     }
434 
435     /* rho <- (r,rp)       */
436     parallel_reduce(Kokkos::TeamVectorRange (team, Nblk), [=] (const int idx, PetscScalar& dot) {dot += R[idx]*PetscConj(RP[idx]);}, rho);
437     team.team_barrier();
438     b    = rho / rhoold;                            /* b <- rho / rhoold   */
439     /* u <- r + b q        */
440     /* p <- u + b(q + b p) */
441     parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {U[idx] = R[idx] + b*Q[idx]; Q[idx] = Q[idx] + b*P[idx]; P[idx] = U[idx] + b*Q[idx];});
442     /* v <- K p  */
443     team.team_barrier();
444     parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {T[idx] = Diag[idx]*P[idx]; });
445     team.team_barrier();
446     MatMult         (team,glb_Aai,glb_Aaj,glb_Aaa,r,ic,start,end,T,V);
447 
448     rhoold = rho;
449     dpold  = dp;
450 
451     i++;
452   } while (i<maxit);
453   done:
454   // KSPUnwindPreconditioner
455   parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {XX[idx] = Diag[idx]*XX[idx]; });
456   team.team_barrier();
457   // put x into Plex order
458   parallel_for(Kokkos::TeamVectorRange(team, start, end), [=] (int rowb) {
459       int rowa = ic[rowb];
460       glb_x[rowa] = XX[rowb-start];
461     });
462   metad->its = i+1;
463   if (1) {
464     int nnz;
465     parallel_reduce(Kokkos::TeamVectorRange (team, start, end), [=] (const int idx, int& lsum) {lsum += (glb_Aai[idx+1] - glb_Aai[idx]);}, nnz);
466     metad->flops = 2*(metad->its*(10*Nblk + 2*nnz) + 5*Nblk);
467   } else {
468     metad->flops = 2*(metad->its*(10*Nblk + 2*50*Nblk) + 5*Nblk); // guess
469   }
470   return 0;
471 }
472 
473 // Solve Ax = y with biCG
474 KOKKOS_INLINE_FUNCTION PetscErrorCode BJSolve_BICG(const team_member team, const PetscInt *glb_Aai, const PetscInt *glb_Aaj, const PetscScalar *glb_Aaa, const PetscInt *r, const PetscInt *ic, PetscScalar *work_space_global, const int stride_global, const int nShareVec, PetscScalar *work_space_shared, const int stride_shared, PetscReal rtol, PetscReal atol, PetscReal dtol,PetscInt maxit, Batch_MetaData *metad, const PetscInt start, const PetscInt end, const PetscScalar glb_idiag[], const PetscScalar *glb_b, PetscScalar *glb_x, bool monitor)
475 {
476   using Kokkos::parallel_reduce;
477   using Kokkos::parallel_for;
478   int               Nblk = end-start, i, stride = stride_shared, idx=0; // start in shared mem
479   PetscReal         dp, r0;
480   const PetscScalar *Di = &glb_idiag[start];
481   PetscScalar       *ptr = work_space_shared, dpi, a=1.0, beta, betaold=1.0, b, b2, ma, mac;
482 
483   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
484   PetscScalar       *XX = ptr; ptr += stride;
485   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
486   PetscScalar       *Rl = ptr; ptr += stride;
487   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
488   PetscScalar       *Zl = ptr; ptr += stride;
489   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
490   PetscScalar       *Pl = ptr; ptr += stride;
491   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
492   PetscScalar       *Rr = ptr; ptr += stride;
493   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
494   PetscScalar       *Zr = ptr; ptr += stride;
495   if (idx++ == nShareVec) {ptr = work_space_global; stride = stride_global;}
496   PetscScalar       *Pr = ptr; ptr += stride;
497 
498   /*     r <- b (x is 0) */
499   parallel_for(Kokkos::TeamVectorRange(team, start, end), [=] (int rowb) {
500       int rowa = ic[rowb];
501       //PetscCall(VecCopy(Rr,Rl));
502       Rl[rowb-start] = Rr[rowb-start] = glb_b[rowa];
503       XX[rowb-start] = 0;
504     });
505   team.team_barrier();
506   /*     z <- Br         */
507   parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {Zr[idx] = Di[idx]*Rr[idx]; Zl[idx] = Di[idx]*Rl[idx]; });
508   team.team_barrier();
509   /*    dp <- r'*r       */
510   parallel_reduce(Kokkos::TeamVectorRange (team, Nblk), [=] (const int idx, PetscScalar& lsum) {lsum += Rr[idx]*PetscConj(Rr[idx]);}, dpi);
511   team.team_barrier();
512   r0 = dp = PetscSqrtReal(PetscRealPart(dpi));
513 #if defined(PETSC_USE_DEBUG) && !defined(PETSC_HAVE_SYCL)
514   if (monitor) Kokkos::single (Kokkos::PerTeam (team), [=] () { printf("%3d KSP Residual norm %14.12e \n", 0, (double)dp);});
515 #endif
516   if (dp < atol) {metad->reason = KSP_CONVERGED_ATOL_NORMAL; return 0;}
517   if (0 == maxit) {metad->reason = KSP_DIVERGED_ITS; return 0;}
518   i = 0;
519   do {
520     /*     beta <- r'z     */
521     parallel_reduce(Kokkos::TeamVectorRange (team, Nblk), [=] (const int idx, PetscScalar& dot) {dot += Zr[idx]*PetscConj(Rl[idx]);}, beta);
522     team.team_barrier();
523 #if PCBJKOKKOS_VERBOSE_LEVEL >= 6
524 #if defined(PETSC_USE_DEBUG) && !defined(PETSC_HAVE_SYCL)
525     Kokkos::single (Kokkos::PerTeam (team), [=] () {printf("%7d beta = Z.R = %22.14e \n",i,(double)beta);});
526 #endif
527 #endif
528     if (!i) {
529       if (beta == 0.0) {
530         metad->reason = KSP_DIVERGED_BREAKDOWN_BICG;
531         goto done;
532       }
533       /*     p <- z          */
534       parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {Pr[idx] = Zr[idx]; Pl[idx] = Zl[idx];});
535     } else {
536       b    = beta/betaold;
537       /*     p <- z + b* p   */
538       b2    = PetscConj(b);
539       parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {Pr[idx] = b*Pr[idx] + Zr[idx]; Pl[idx] = b2*Pl[idx] + Zl[idx];});
540     }
541     team.team_barrier();
542     betaold = beta;
543     /*     z <- Kp         */
544     MatMult         (team,glb_Aai,glb_Aaj,glb_Aaa,r,ic,start,end,Pr,Zr);
545     MatMultTranspose(team,glb_Aai,glb_Aaj,glb_Aaa,r,ic,start,end,Pl,Zl);
546     /*     dpi <- z'p      */
547     parallel_reduce(Kokkos::TeamVectorRange (team, Nblk), [=] (const int idx, PetscScalar& lsum) {lsum += Zr[idx]*PetscConj(Pl[idx]);}, dpi);
548     team.team_barrier();
549     //
550     a       = beta/dpi;                           /*     a = beta/p'z    */
551     ma      = -a;
552     mac      = PetscConj(ma);
553     /*     x <- x + ap     */
554     parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {XX[idx] = XX[idx] + a*Pr[idx]; Rr[idx] = Rr[idx] + ma*Zr[idx]; Rl[idx] = Rl[idx] + mac*Zl[idx];});team.team_barrier();
555     team.team_barrier();
556     /*    dp <- r'*r       */
557     parallel_reduce(Kokkos::TeamVectorRange (team, Nblk), [=] (const int idx, PetscScalar& lsum) {lsum +=  Rr[idx]*PetscConj(Rr[idx]);}, dpi);
558     team.team_barrier();
559     dp = PetscSqrtReal(PetscRealPart(dpi));
560 #if defined(PETSC_USE_DEBUG) && !defined(PETSC_HAVE_SYCL)
561     if (monitor) Kokkos::single (Kokkos::PerTeam (team), [=] () { printf("%3d KSP Residual norm %14.12e \n", i+1, (double)dp);});
562 #endif
563     if (dp < atol) {metad->reason = KSP_CONVERGED_ATOL_NORMAL; goto done;}
564     if (dp/r0 < rtol) {metad->reason = KSP_CONVERGED_RTOL_NORMAL; goto done;}
565 #if defined(PETSC_USE_DEBUG) && !defined(PETSC_HAVE_SYCL)
566     if (dp/r0 > dtol) {metad->reason = KSP_DIVERGED_DTOL; Kokkos::single (Kokkos::PerTeam (team), [=] () {printf("ERROR block %d diverged: %d it, res=%e, r_0=%e\n",team.league_rank(),i,dp,r0);}); goto done;}
567 #else
568     if (dp/r0 > dtol) {metad->reason = KSP_DIVERGED_DTOL; goto done;}
569 #endif
570     if (i+1 == maxit) {metad->reason = KSP_DIVERGED_ITS; goto done;}
571     /* z <- Br  */
572     parallel_for(Kokkos::TeamVectorRange(team,Nblk), [=] (int idx) {Zr[idx] = Di[idx]*Rr[idx]; Zl[idx] = Di[idx]*Rl[idx];});
573     i++;
574     team.team_barrier();
575   } while (i<maxit);
576  done:
577   // put x back into Plex order
578   parallel_for(Kokkos::TeamVectorRange(team, start, end), [=] (int rowb) {
579       int rowa = ic[rowb];
580       glb_x[rowa] = XX[rowb-start];
581     });
582   metad->its = i+1;
583   if (1) {
584     int nnz;
585     parallel_reduce(Kokkos::TeamVectorRange (team, start, end), [=] (const int idx, int& lsum) {lsum += (glb_Aai[idx+1] - glb_Aai[idx]);}, nnz);
586     metad->flops = 2*(metad->its*(10*Nblk + 2*nnz) + 5*Nblk);
587   } else {
588     metad->flops = 2*(metad->its*(10*Nblk + 2*50*Nblk) + 5*Nblk); // guess
589   }
590   return 0;
591 }
592 
593 // KSP solver solve Ax = b; x is output, bin is input
594 static PetscErrorCode PCApply_BJKOKKOS(PC pc,Vec bin,Vec xout)
595 {
596   PC_PCBJKOKKOS    *jac = (PC_PCBJKOKKOS*)pc->data;
597   Mat               A   = pc->pmat;
598   Mat_SeqAIJKokkos *aijkok;
599 
600   PetscFunctionBegin;
601   PetscCheck(jac->vec_diag && A,PetscObjectComm((PetscObject)pc),PETSC_ERR_USER,"Not setup???? %p %p",jac->vec_diag,A);
602   aijkok = static_cast<Mat_SeqAIJKokkos*>(A->spptr);
603   if (!aijkok) {
604     SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_USER,"No aijkok");
605   } else {
606     PetscInt          maxit = jac->ksp->max_it;
607     const PetscInt    conc = Kokkos::DefaultExecutionSpace().concurrency(), openmp = !!(conc < 1000), team_size = (openmp==0 && PCBJKOKKOS_VEC_SIZE != 1) ? PCBJKOKKOS_TEAM_SIZE : 1;
608     const PetscInt    nwork = jac->nwork, nBlk = jac->nBlocks;
609     PetscScalar       *glb_xdata=NULL;
610     PetscReal         rtol = jac->ksp->rtol, atol = jac->ksp->abstol, dtol = jac->ksp->divtol;
611     const PetscScalar *glb_idiag =jac->d_idiag_k->data(), *glb_bdata=NULL;
612     const PetscInt    *glb_Aai = aijkok->i_device_data(), *glb_Aaj = aijkok->j_device_data(), *d_bid_eqOffset = jac->d_bid_eqOffset_k->data();
613     const PetscScalar *glb_Aaa = aijkok->a_device_data();
614     const PetscInt    *d_isicol = jac->d_isicol_k->data(), *d_isrow = jac->d_isrow_k->data();
615     PCFailedReason    pcreason;
616     KSPIndex          ksp_type_idx = jac->ksp_type_idx;
617     PetscMemType      mtype;
618     PetscContainer    container;
619     PetscInt          batch_sz;
620     VecScatter        plex_batch=NULL; // not used
621     Vec               bvec; // a copy of b for scatter (just alias to bin now)
622     PetscBool         monitor = jac->monitor; // captured
623     PetscInt          view_bid = jac->batch_target;
624     MatInfo           info;
625     jac->max_nits = 0;
626     if (view_bid<0) view_bid = 0;
627     PetscCall(MatGetInfo(A,MAT_LOCAL,&info));
628     // get field major is to map plex IO to/from block/field major
629     PetscCall(PetscObjectQuery((PetscObject) A, "plex_batch_is", (PetscObject *) &container));
630     if (container) {
631       PetscCall(VecDuplicate(bin,&bvec));
632       PetscCall(PetscContainerGetPointer(container, (void **) &plex_batch));
633       PetscCall(VecScatterBegin(plex_batch,bin,bvec,INSERT_VALUES,SCATTER_FORWARD));
634       PetscCall(VecScatterEnd(plex_batch,bin,bvec,INSERT_VALUES,SCATTER_FORWARD));
635       SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_USER,"No plex_batch_is -- require NO field major ordering for now");
636     } else {
637       bvec = bin;
638     }
639     // get x
640     PetscCall(VecGetArrayAndMemType(xout,&glb_xdata,&mtype));
641 #if defined(PETSC_HAVE_CUDA)
642     PetscCheck(PetscMemTypeDevice(mtype),PetscObjectComm((PetscObject) pc),PETSC_ERR_ARG_WRONG,"No GPU data for x %" PetscInt_FMT " != %" PetscInt_FMT,mtype,PETSC_MEMTYPE_DEVICE);
643 #endif
644     PetscCall(VecGetArrayReadAndMemType(bvec,&glb_bdata,&mtype));
645 #if defined(PETSC_HAVE_CUDA)
646     PetscCheck(PetscMemTypeDevice(mtype),PetscObjectComm((PetscObject) pc),PETSC_ERR_ARG_WRONG,"No GPU data for b");
647 #endif
648     // get batch size
649     PetscCall(PetscObjectQuery((PetscObject) A, "batch size", (PetscObject *) &container));
650     if (container) {
651       PetscInt *pNf=NULL;
652       PetscCall(PetscContainerGetPointer(container, (void **) &pNf));
653       batch_sz = *pNf;
654     } else batch_sz = 1;
655     PetscCheck(nBlk%batch_sz==0,PetscObjectComm((PetscObject) pc),PETSC_ERR_ARG_WRONG,"batch_sz = %" PetscInt_FMT ", nBlk = %" PetscInt_FMT,batch_sz,nBlk);
656     if (ksp_type_idx==BATCH_KSP_GMRES_IDX) { // KK solver - move PETSc data into Kokkos Views, setup solver, solve, move data out of Kokkos, process metadata (convergence tests, etc.)
657 #if defined(PETSC_HAVE_KOKKOS_KERNELS_GMRES)
658       int Nsolves_team = jac->nsolves_team, fill_idx=0;
659       int Nloc = jac->const_block_size; // same grids
660       const int Nsolves = nBlk;
661       const int nnz = (int)info.nz_used / Nsolves; // fix for variable grid size
662       if (Nsolves_team > batch_sz) Nsolves_team = batch_sz; // silently fix this
663       PetscCheck(jac->const_block_size,PetscObjectComm((PetscObject) pc),PETSC_ERR_ARG_WRONG,"Kokkos (GMRES) solver requires constant block size (but can be made to work with species ordering or N_team==1)");
664       PetscCheck(Nsolves%Nsolves_team==0, PetscObjectComm((PetscObject) pc), PETSC_ERR_ARG_WRONG, "Nsolves.mod(Nsolves_team) != 0: Nsolves = %d, Nsolves_team = %d", Nsolves, Nsolves_team);
665       PetscCheck(((int)info.nz_used)%Nsolves==0, PetscObjectComm((PetscObject) pc), PETSC_ERR_ARG_WRONG, "info.nz_used.mod(Nsolves) != 0: info.nz_used = %g, Nsolves = %d", info.nz_used, Nsolves);
666 #if defined(PETSC_HAVE_CUDA_NVTX)
667       nvtxRangePushA("gmres-kk");
668 #endif
669       Kokkos::View<PetscScalar **, layout, exec_space, Kokkos::MemoryTraits<Kokkos::Unmanaged>> inv_diag((PetscScalar*)glb_idiag, Nsolves, Nloc); // in correct order
670       if (!jac->rowOffsets) {
671         jac->rowOffsets          = new IntView("rowOffsets", Nsolves/Nsolves_team, Nloc+1);    // same grids
672         jac->colIndices          = new IntView("colIndices", Nsolves/Nsolves_team, nnz);
673         jac->batch_b             = new XYType("batch rhs", Nsolves, Nloc);
674         jac->batch_x             = new XYType("batch sol", Nsolves, Nloc);
675         jac->batch_values        = new AMatrixValueView("batch values", Nsolves, nnz);
676         fill_idx = 1;
677         PetscInfo(pc,"Setup indices Nloc=%d, nnz=%d\n",Nloc,nnz);
678       }
679       IntView &rowOffsets = *jac->rowOffsets;
680       IntView &colIndices = *jac->colIndices;
681       XYType &batch_b = *jac->batch_b;
682       XYType &batch_x = *jac->batch_x;
683       AMatrixValueView &batch_values = *jac->batch_values;
684 
685       Kokkos::deep_copy(batch_x, 0.);
686       PetscInfo(pc,"\tjac->n = %" PetscInt_FMT ", Nloc = %d, Nsolves = %d, nnz = %d, Nsolves_team = %d, league size = %d, maxit = %" PetscInt_FMT "\n",jac->n,Nloc,Nsolves,nnz,Nsolves_team,Nsolves/Nsolves_team,maxit);
687       Kokkos::parallel_for
688         ("rowOffsets+map", Kokkos::TeamPolicy<>(Nsolves, team_size, PCBJKOKKOS_VEC_SIZE),
689          KOKKOS_LAMBDA (const team_member team) {
690           const int blkID = team.league_rank(), start = d_bid_eqOffset[blkID], end = d_bid_eqOffset[blkID+1];
691           if (fill_idx) {
692             if (blkID%Nsolves_team == 0) { // first matrix on this member
693               Kokkos::parallel_for(Kokkos::TeamVectorRange(team,start,end), [=] (const int rowb) { // Nloc
694                   int rowa = d_isicol[rowb];
695                   int n    = glb_Aai[rowa+1] - glb_Aai[rowa];
696                   rowOffsets(blkID/Nsolves_team,rowb+1-start) = n; // save sizes
697                 });
698             }
699           }
700           // map b into field major space
701           Kokkos::parallel_for(Kokkos::TeamVectorRange(team, start, end), [=] (int rowb) {
702               int rowa = d_isicol[rowb];
703               batch_b(blkID, rowb-start) = glb_bdata[rowa];
704             });
705         });
706       Kokkos::fence();
707       if (fill_idx) {
708         Kokkos::parallel_for
709           ("prefix sum", Kokkos::TeamPolicy<>(Nsolves/Nsolves_team, 1, 1),
710            KOKKOS_LAMBDA (const team_member team) {
711             const int graphID = team.league_rank();
712             rowOffsets(graphID,0) = 0;
713             for (size_t i = 0; i < Nloc; ++i) rowOffsets(graphID,i+1) += rowOffsets(graphID,i);
714           });
715         Kokkos::fence();
716       }
717       Kokkos::parallel_for
718         ("copy matrix", Kokkos::TeamPolicy<>(Nsolves /* /batch_sz */, team_size, PCBJKOKKOS_VEC_SIZE),
719          KOKKOS_LAMBDA (const team_member team) {
720           const int blkID = team.league_rank(), start = d_bid_eqOffset[blkID], end = d_bid_eqOffset[blkID+1], graphID = blkID/Nsolves_team;
721           Kokkos::parallel_for(Kokkos::TeamThreadRange(team,start,end), [=] (const int rowb) {
722               int rowa = d_isicol[rowb]; // global index
723               int n    = glb_Aai[rowa+1] - glb_Aai[rowa];
724               const PetscInt    *aj = glb_Aaj + glb_Aai[rowa];
725               const PetscScalar *aa = glb_Aaa + glb_Aai[rowa];
726               Kokkos::parallel_for(Kokkos::ThreadVectorRange(team,n), [=] (const int &i) {
727                   PetscScalar val  = aa[i];
728                   if (fill_idx && blkID%Nsolves_team==0) colIndices(graphID, rowOffsets(graphID,rowb-start) + i) = d_isrow[aj[i]] - blkID*Nloc; // local" global - block start
729                   batch_values(                                     blkID,   rowOffsets(graphID,rowb-start) + i) = val;
730                 });
731             });
732         });
733       Kokkos::fence();
734       // setup solver
735       using ScalarType = typename AMatrixValueView::non_const_value_type;
736       using MagnitudeType = typename Kokkos::Details::ArithTraits<ScalarType>::mag_type;
737       using NormViewType = Kokkos::View<MagnitudeType *, layout, exec_space>;
738       using Norm2DViewType = Kokkos::View<MagnitudeType **, layout, exec_space>;
739       using Scalar3DViewType = Kokkos::View<ScalarType ***, layout, exec_space>;
740       using IntViewType = Kokkos::View<int*, layout, exec_space>;
741       using KrylovHandleType = KokkosBatched::KrylovHandle<Norm2DViewType, IntViewType, Scalar3DViewType>;
742       const int n_iterations = maxit;
743       const int team_size = -1;
744       const int vector_length = -1;
745       const double tol = rtol;
746       const int ortho_strategy = 0;
747       KrylovHandleType handle(Nsolves, Nsolves_team, n_iterations, true);
748       handle.Arnoldi_view = Scalar3DViewType("", Nsolves, n_iterations, Nloc+n_iterations+3);
749       // solve
750       double time = Functor_TestBatchedTeamVectorGMRES<exec_space, AMatrixValueView, IntView, XYType, KrylovHandleType>
751         (batch_values, inv_diag, rowOffsets, colIndices, batch_x, batch_b, Nsolves_team, team_size, vector_length, n_iterations, tol, ortho_strategy, 0, handle).run(pc);
752       Kokkos::fence();
753       // get data back
754       Kokkos::parallel_for
755         ("map", Kokkos::TeamPolicy<>(Nsolves /* /batch_sz */, team_size, PCBJKOKKOS_VEC_SIZE),
756          KOKKOS_LAMBDA (const team_member team) {
757           const int blkID = team.league_rank(), start = d_bid_eqOffset[blkID], end = d_bid_eqOffset[blkID+1]; // 0
758           // map x into Plex/PETSc
759           Kokkos::parallel_for(Kokkos::TeamVectorRange(team, start, end), [=] (int rowb) {
760               int rowa = d_isicol[rowb];
761               glb_xdata[rowa] = batch_x(blkID, rowb-start);
762             });
763         });
764       // output assume species major - clone from Kokkos solvers
765 #if PCBJKOKKOS_VERBOSE_LEVEL >= 3
766 #if PCBJKOKKOS_VERBOSE_LEVEL >= 4
767       PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),"Iterations\n"));
768 #else
769       PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),"max iterations per species (gmres) :"));
770 #endif
771       for (PetscInt dmIdx=0, s=0, head=0 ; dmIdx < jac->num_dms; dmIdx += batch_sz) {
772         for (PetscInt f=0, idx=head ; f < jac->dm_Nf[dmIdx] ; f++,s++,idx++) {
773 #if PCBJKOKKOS_VERBOSE_LEVEL >= 4
774           PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),"%2D:", s));
775           for (int bid=0 ; bid<batch_sz ; bid++) {
776             PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),"%3D ", handle.get_iteration_host(idx + bid*jac->dm_Nf[dmIdx])));
777           }
778           PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),"\n"));
779 #else
780           int count=0, ii;
781           for (int bid=0 ; bid<batch_sz ; bid++) {
782             if ((ii=handle.get_iteration_host(idx + bid*jac->dm_Nf[dmIdx])) > count) count = ii;
783           }
784           PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),"%3d", count));
785 #endif
786         }
787         head += batch_sz*jac->dm_Nf[dmIdx];
788       }
789 #if PCBJKOKKOS_VERBOSE_LEVEL == 3
790       PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),"\n"));
791 #endif
792 #endif
793       // return error code, get max it
794       PetscInt count=0, mbid=0;
795       if (handle.is_converged_host()) {
796         pcreason = PC_NOERROR;
797         if (!jac->max_nits) {
798           for (int blkID=0;blkID<nBlk;blkID++) {
799             if (handle.get_iteration_host(blkID) > jac->max_nits) {
800               jac->max_nits = handle.get_iteration_host(blkID);
801               mbid = blkID;
802             }
803           }
804         }
805       } else {
806         PetscCall(PetscPrintf(PETSC_COMM_SELF,"There is at least one system that did not converge."));
807         pcreason = PC_SUBPC_ERROR;
808       }
809       // output - assume species major order
810       for (int blkID=0;blkID<nBlk;blkID++) {
811         if (jac->reason) { // -pc_bjkokkos_ksp_converged_reason
812           if (jac->batch_target==blkID) {
813             PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),  "    Linear solve %s in %d iterations, batch %" PetscInt_FMT ", species %" PetscInt_FMT "\n", handle.is_converged_host(blkID) ? "converged" : "diverged", handle.get_iteration_host(blkID), blkID%batch_sz, blkID/batch_sz));
814           } else if (jac->batch_target==-1 && handle.get_iteration_host(blkID) > count) {
815             jac->max_nits = count = handle.get_iteration_host(blkID);
816             mbid = blkID;
817           }
818           if (!handle.is_converged_host(blkID)) {
819             PetscCall(PetscPrintf(PETSC_COMM_SELF,"ERROR species %d, batch %d did not converge with %d iterations\n",(int)(blkID/batch_sz),(int)blkID%batch_sz,handle.get_iteration_host(blkID)));
820           }
821         }
822       }
823       if (jac->batch_target==-1 && jac->reason) {
824         PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),  "    Linear solve %s in %d iteration, batch %" PetscInt_FMT ", specie %" PetscInt_FMT "\n", handle.is_converged_host(mbid) ? "converged" : "diverged",jac->max_nits,mbid%batch_sz,mbid/batch_sz));
825       }
826 #if defined(PETSC_HAVE_CUDA_NVTX)
827       nvtxRangePop();
828 #endif
829 #else
830       SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_USER,"batch GMRES not supported");
831 #endif
832     } else { // Kokkos Krylov
833       using scr_mem_t  = Kokkos::DefaultExecutionSpace::scratch_memory_space;
834       using vect2D_scr_t = Kokkos::View<PetscScalar**, Kokkos::LayoutLeft, scr_mem_t>;
835       Kokkos::View<Batch_MetaData*, Kokkos::DefaultExecutionSpace> d_metadata("solver meta data", nBlk);
836       int stride_shared, stride_global, global_buff_words;
837       d_bid_eqOffset = jac->d_bid_eqOffset_k->data();
838       // solve each block independently
839       int scr_bytes_team_shared = 0, nShareVec = 0, nGlobBVec = 0;
840       if (jac->const_block_size) { // use shared memory for work vectors only if constant block size - todo: test efficiency loss
841         int maximum_shared_mem_size;
842         stride_shared = jac->const_block_size; // captured
843 #if defined(PETSC_HAVE_CUDA)
844         int device;
845         cudaError_t ier = cudaGetDevice(&device);
846         ier = cudaDeviceGetAttribute(&maximum_shared_mem_size, cudaDevAttrMaxSharedMemoryPerBlock, device);
847 #elif defined(PETSC_HAVE_HIP)
848         int device;
849         hipGetDevice(&device);
850         hipDeviceGetAttribute(&maximum_shared_mem_size, hipDeviceAttributeMaxSharedMemoryPerBlock, device);
851 #elif defined(PETSC_HAVE_SYCL)
852         maximum_shared_mem_size = 64000;
853 #else
854         maximum_shared_mem_size = 72000;
855 #endif
856         nShareVec = maximum_shared_mem_size / (jac->const_block_size*sizeof(PetscScalar)); // integer floor, number of vectors that fit in shared
857         if (nShareVec > nwork) nShareVec = nwork;
858         else nGlobBVec = nwork - nShareVec;
859         global_buff_words = jac->n*nGlobBVec;
860         scr_bytes_team_shared = jac->const_block_size*nShareVec*sizeof(PetscScalar);
861         //PetscCall(PetscPrintf(PETSC_COMM_WORLD,"maximum_shared_mem_size=%d scr_bytes_shared=%d nShareVec=%d, nGlobBVec=%d vec size=%d jac->const_block_size=%d\n",maximum_shared_mem_size,scr_bytes_team_shared,nShareVec,nGlobBVec,jac->const_block_size*sizeof(PetscScalar),jac->const_block_size));
862       } else {
863         scr_bytes_team_shared = 0;
864         stride_shared = 0;
865         global_buff_words = jac->n*nwork;
866         nGlobBVec = nwork; // not needed == fix
867       }
868       stride_global = jac->n; // captured
869 #if defined(PETSC_HAVE_CUDA_NVTX)
870       nvtxRangePushA("batch-kokkos-solve");
871 #endif
872       Kokkos::View<PetscScalar*, Kokkos::DefaultExecutionSpace> d_work_vecs_k("workvectors", global_buff_words); // global work vectors
873       PetscInfo(pc,"\tn = %d. %d shared bytes/team, %d global mem bytes, rtol=%e, num blocks %d, team_size=%d, %d vector threads, %d shared vectors, %d global vectors\n",(int)jac->n, scr_bytes_team_shared, global_buff_words, rtol, (int)nBlk, (int)team_size, PCBJKOKKOS_VEC_SIZE,nShareVec,nGlobBVec);
874       PetscScalar  *d_work_vecs = d_work_vecs_k.data();
875       Kokkos::parallel_for
876         ("Solve", Kokkos::TeamPolicy<>(nBlk, team_size, PCBJKOKKOS_VEC_SIZE).set_scratch_size(PCBJKOKKOS_SHARED_LEVEL, Kokkos::PerTeam(scr_bytes_team_shared)),
877          KOKKOS_LAMBDA (const team_member team) {
878           const int    blkID = team.league_rank(), start = d_bid_eqOffset[blkID], end = d_bid_eqOffset[blkID+1];
879           vect2D_scr_t work_vecs_shared(team.team_scratch(PCBJKOKKOS_SHARED_LEVEL), end-start, nShareVec);
880           PetscScalar  *work_buff_shared = work_vecs_shared.data();
881           PetscScalar  *work_buff_global = &d_work_vecs[start]; // start inc'ed in
882           bool         print = monitor && (blkID==view_bid);
883           switch (ksp_type_idx) {
884           case BATCH_KSP_BICG_IDX:
885             BJSolve_BICG(team, glb_Aai, glb_Aaj, glb_Aaa, d_isrow, d_isicol, work_buff_global, stride_global, nShareVec, work_buff_shared, stride_shared, rtol, atol, dtol, maxit, &d_metadata[blkID], start, end, glb_idiag, glb_bdata, glb_xdata, print);
886             break;
887           case BATCH_KSP_TFQMR_IDX:
888             BJSolve_TFQMR(team, glb_Aai, glb_Aaj, glb_Aaa, d_isrow, d_isicol,work_buff_global, stride_global, nShareVec, work_buff_shared, stride_shared, rtol, atol, dtol, maxit, &d_metadata[blkID], start, end, glb_idiag, glb_bdata, glb_xdata, print);
889             break;
890           case BATCH_KSP_GMRES_IDX:
891             //BJSolve_GMRES();
892             break;
893           default:
894 #if defined(PETSC_USE_DEBUG) && !defined(PETSC_HAVE_SYCL)
895             printf("Unknown KSP type %d\n",ksp_type_idx);
896 #else
897             /* void */;
898 #endif
899           }
900         });
901       Kokkos::fence();
902 #if defined(PETSC_HAVE_CUDA_NVTX)
903       nvtxRangePop();
904       nvtxRangePushA("Post-solve-metadata");
905 #endif
906       auto h_metadata = Kokkos::create_mirror(Kokkos::HostSpace::memory_space(), d_metadata);
907       Kokkos::deep_copy (h_metadata, d_metadata);
908 #if PCBJKOKKOS_VERBOSE_LEVEL >= 3
909 #if PCBJKOKKOS_VERBOSE_LEVEL >= 4
910       PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Iterations\n"));
911 #endif
912       // assume species major
913 #if PCBJKOKKOS_VERBOSE_LEVEL < 4
914       PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),"max iterations per species (%s) :",ksp_type_idx==BATCH_KSP_BICG_IDX ? "bicg" : "tfqmr"));
915 #endif
916       for (PetscInt dmIdx=0, s=0, head=0 ; dmIdx < jac->num_dms; dmIdx += batch_sz) {
917         for (PetscInt f=0, idx=head ; f < jac->dm_Nf[dmIdx] ; f++,s++,idx++) {
918 #if PCBJKOKKOS_VERBOSE_LEVEL >= 4
919           PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),"%2" PetscInt_FMT ":", s));
920           for (int bid=0 ; bid<batch_sz ; bid++) {
921             PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),"%3" PetscInt_FMT " ", h_metadata[idx + bid*jac->dm_Nf[dmIdx]].its));
922           }
923           PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),"\n"));
924 #else
925           PetscInt count=0;
926           for (int bid=0 ; bid<batch_sz ; bid++) {
927             if (h_metadata[idx + bid*jac->dm_Nf[dmIdx]].its > count) count = h_metadata[idx + bid*jac->dm_Nf[dmIdx]].its;
928           }
929           PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),"%3" PetscInt_FMT " ", count));
930 #endif
931         }
932         head += batch_sz*jac->dm_Nf[dmIdx];
933       }
934 #if PCBJKOKKOS_VERBOSE_LEVEL == 3
935       PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),"\n"));
936 #endif
937 #endif
938       PetscInt count=0, mbid=0;
939       for (int blkID=0;blkID<nBlk;blkID++) {
940         PetscCall(PetscLogGpuFlops((PetscLogDouble)h_metadata[blkID].flops));
941         if (jac->reason) { // -pc_bjkokkos_ksp_converged_reason
942           if (jac->batch_target==blkID) {
943             PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),  "    Linear solve converged due to %s iterations %d, batch %" PetscInt_FMT ", species %" PetscInt_FMT "\n", KSPConvergedReasons[h_metadata[blkID].reason], h_metadata[blkID].its, blkID%batch_sz, blkID/batch_sz));
944           } else if (jac->batch_target==-1 && h_metadata[blkID].its > count) {
945             jac->max_nits = count = h_metadata[blkID].its;
946             mbid = blkID;
947           }
948           if (h_metadata[blkID].reason < 0) {
949             PetscCall(PetscPrintf(PETSC_COMM_SELF, "ERROR reason=%s, its=%" PetscInt_FMT ". species %" PetscInt_FMT ", batch %" PetscInt_FMT "\n",
950                                   KSPConvergedReasons[h_metadata[blkID].reason],h_metadata[blkID].its,blkID/batch_sz,blkID%batch_sz));
951           }
952         }
953       }
954       if (jac->batch_target==-1 && jac->reason) {
955         PetscCall(PetscPrintf(PetscObjectComm((PetscObject)A),"    Linear solve converged due to %s iterations %d, batch %" PetscInt_FMT ", specie %" PetscInt_FMT "\n", KSPConvergedReasons[h_metadata[mbid].reason], h_metadata[mbid].its, mbid%batch_sz, mbid/batch_sz));
956       }
957       {
958         int errsum;
959         Kokkos::parallel_reduce(nBlk, KOKKOS_LAMBDA (const int idx, int& lsum) {
960             if (d_metadata[idx].reason < 0) ++lsum;
961           }, errsum);
962         pcreason = errsum ? PC_SUBPC_ERROR : PC_NOERROR;
963         if (!errsum && !jac->max_nits) { // set max its to give back to top KSP
964           for (int blkID=0;blkID<nBlk;blkID++) {
965             if (h_metadata[blkID].its > jac->max_nits) jac->max_nits = h_metadata[blkID].its;
966           }
967         } else if (errsum) {
968           PetscCall(PetscPrintf(PETSC_COMM_SELF,"ERROR Kokkos batch solver did not converge in all solves\n"));
969         }
970       }
971 #if defined(PETSC_HAVE_CUDA_NVTX)
972       nvtxRangePop();
973 #endif
974     } // end of Kokkos (not Kernels) solvers block
975     PetscCall(VecRestoreArrayAndMemType(xout,&glb_xdata));
976     PetscCall(VecRestoreArrayReadAndMemType(bvec,&glb_bdata));
977     PetscCall(PCSetFailedReason(pc,pcreason));
978     // map back to Plex space - not used
979     if (plex_batch) {
980       PetscCall(VecCopy(xout, bvec));
981       PetscCall(VecScatterBegin(plex_batch,bvec,xout,INSERT_VALUES,SCATTER_REVERSE));
982       PetscCall(VecScatterEnd(plex_batch,bvec,xout,INSERT_VALUES,SCATTER_REVERSE));
983       PetscCall(VecDestroy(&bvec));
984     }
985   } // whole 'have aijkok' block
986   PetscFunctionReturn(0);
987 }
988 
989 static PetscErrorCode PCSetUp_BJKOKKOS(PC pc)
990 {
991   PC_PCBJKOKKOS    *jac = (PC_PCBJKOKKOS*)pc->data;
992   Mat               A   = pc->pmat;
993   Mat_SeqAIJKokkos *aijkok;
994   PetscBool         flg;
995 
996   PetscFunctionBegin;
997   PetscCheck(!pc->useAmat,PetscObjectComm((PetscObject)pc),PETSC_ERR_SUP,"No support for using 'use_amat'");
998   PetscCheck(A,PetscObjectComm((PetscObject)A),PETSC_ERR_USER,"No matrix - A is used above");
999   PetscCall(PetscObjectTypeCompareAny((PetscObject)A,&flg,MATSEQAIJKOKKOS,MATMPIAIJKOKKOS,MATAIJKOKKOS,""));
1000   PetscCheck(flg,PetscObjectComm((PetscObject)A),PETSC_ERR_ARG_WRONG,"must use '-dm_mat_type aijkokkos -dm_vec_type kokkos' for -pc_type bjkokkos");
1001   if (!(aijkok = static_cast<Mat_SeqAIJKokkos*>(A->spptr))) {
1002     SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_USER,"No aijkok");
1003   } else {
1004     if (!jac->vec_diag) {
1005       Vec               *subX;
1006       DM                pack,*subDM;
1007       PetscInt          nDMs, n;
1008       PetscContainer    container;
1009       PetscCall(PetscObjectQuery((PetscObject) A, "plex_batch_is", (PetscObject *) &container));
1010       { // Permute the matrix to get a block diagonal system: d_isrow_k, d_isicol_k
1011         MatOrderingType   rtype;
1012         IS                isrow,isicol;
1013         const PetscInt    *rowindices,*icolindices;
1014         rtype = MATORDERINGRCM;
1015         // get permutation. Not what I expect so inverted here
1016         PetscCall(MatGetOrdering(A,rtype,&isrow,&isicol));
1017         PetscCall(ISDestroy(&isrow));
1018         PetscCall(ISInvertPermutation(isicol,PETSC_DECIDE,&isrow)); // THIS IS BACKWARD -- isrow is inverse -- FIX!!!!!
1019 
1020         Mat mat_block_order;
1021         PetscCall(MatCreateSubMatrix(A,isicol,isicol,MAT_INITIAL_MATRIX,&mat_block_order));
1022         PetscCall(MatViewFromOptions(mat_block_order, NULL, "-ksp_batch_reorder_view"));
1023         PetscCall(MatDestroy(&mat_block_order));
1024 
1025         PetscCall(ISGetIndices(isrow,&rowindices));
1026         PetscCall(ISGetIndices(isicol,&icolindices));
1027         const Kokkos::View<PetscInt*, Kokkos::HostSpace, Kokkos::MemoryTraits<Kokkos::Unmanaged> > h_isrow_k((PetscInt*)rowindices,A->rmap->n);
1028         const Kokkos::View<PetscInt*, Kokkos::HostSpace, Kokkos::MemoryTraits<Kokkos::Unmanaged> > h_isicol_k ((PetscInt*)icolindices,A->rmap->n);
1029         jac->d_isrow_k = new Kokkos::View<PetscInt*>(Kokkos::create_mirror(DefaultMemorySpace(),h_isrow_k));
1030         jac->d_isicol_k = new Kokkos::View<PetscInt*>(Kokkos::create_mirror(DefaultMemorySpace(),h_isicol_k));
1031         Kokkos::deep_copy (*jac->d_isrow_k, h_isrow_k);
1032         Kokkos::deep_copy (*jac->d_isicol_k, h_isicol_k);
1033         PetscCall(ISRestoreIndices(isrow,&rowindices));
1034         PetscCall(ISRestoreIndices(isicol,&icolindices));
1035         PetscCall(ISDestroy(&isrow));
1036         PetscCall(ISDestroy(&isicol));
1037       }
1038       // get block sizes
1039       PetscCall(PCGetDM(pc, &pack));
1040       PetscCheck(pack,PetscObjectComm((PetscObject)A),PETSC_ERR_USER,"no DM. Requires a composite DM");
1041       PetscCall(PetscObjectTypeCompare((PetscObject)pack,DMCOMPOSITE,&flg));
1042       PetscCheck(flg,PetscObjectComm((PetscObject)pack),PETSC_ERR_USER,"Not for type %s",((PetscObject)pack)->type_name);
1043       PetscCall(DMCompositeGetNumberDM(pack,&nDMs));
1044       jac->num_dms = nDMs;
1045       PetscCall(DMCreateGlobalVector(pack, &jac->vec_diag));
1046       PetscCall(VecGetLocalSize(jac->vec_diag,&n));
1047       jac->n = n;
1048       jac->d_idiag_k = new Kokkos::View<PetscScalar*, Kokkos::LayoutRight>("idiag", n);
1049       // options
1050       PetscCall(PCBJKOKKOSCreateKSP_BJKOKKOS(pc));
1051       PetscCall(KSPSetFromOptions(jac->ksp));
1052       PetscCall(PetscObjectTypeCompareAny((PetscObject)jac->ksp,&flg,KSPBICG,""));
1053       if (flg) {jac->ksp_type_idx = BATCH_KSP_BICG_IDX; jac->nwork = 7;}
1054       else {
1055         PetscCall(PetscObjectTypeCompareAny((PetscObject)jac->ksp,&flg,KSPTFQMR,""));
1056         if (flg) {jac->ksp_type_idx = BATCH_KSP_TFQMR_IDX; jac->nwork = 10;}
1057         else {
1058           PetscCall(PetscObjectTypeCompareAny((PetscObject)jac->ksp,&flg,KSPGMRES,""));
1059           if (flg) {jac->ksp_type_idx = BATCH_KSP_GMRES_IDX; jac->nwork = 0;}
1060           else {
1061             SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_ARG_WRONG,"Unsupported batch ksp type");
1062           }
1063         }
1064       }
1065       PetscOptionsBegin(PetscObjectComm((PetscObject)jac->ksp), ((PetscObject)jac->ksp)->prefix, "Options for Kokkos batch solver", "none");
1066       PetscCall(PetscOptionsBool("-ksp_converged_reason","","bjkokkos.kokkos.cxx.c",jac->reason, &jac->reason, NULL));
1067       PetscCall(PetscOptionsBool("-ksp_monitor","","bjkokkos.kokkos.cxx.c",jac->monitor,&jac->monitor, NULL));
1068       PetscCall(PetscOptionsInt("-ksp_batch_target", "", "bjkokkos.kokkos.cxx.c", jac->batch_target, &jac->batch_target, NULL));
1069       PetscCall(PetscOptionsInt("-ksp_batch_nsolves_team", "", "bjkokkos.kokkos.cxx.c", jac->nsolves_team, &jac->nsolves_team, NULL));
1070       PetscCheck(jac->batch_target < jac->num_dms,PETSC_COMM_WORLD,PETSC_ERR_ARG_WRONG,"-ksp_batch_target (%" PetscInt_FMT ") >= number of DMs (%" PetscInt_FMT ")",jac->batch_target,jac->num_dms);
1071       PetscOptionsEnd();
1072       // get blocks - jac->d_bid_eqOffset_k
1073       PetscCall(PetscMalloc(sizeof(*subX)*nDMs, &subX));
1074       PetscCall(PetscMalloc(sizeof(*subDM)*nDMs, &subDM));
1075       PetscCall(PetscMalloc(sizeof(*jac->dm_Nf)*nDMs, &jac->dm_Nf));
1076       PetscCall(PetscInfo(pc, "Have %" PetscInt_FMT " DMs, n=%" PetscInt_FMT " rtol=%g type = %s\n", nDMs, n, (double)jac->ksp->rtol, ((PetscObject)jac->ksp)->type_name));
1077       PetscCall(DMCompositeGetEntriesArray(pack,subDM));
1078       jac->nBlocks = 0;
1079       for (PetscInt ii=0;ii<nDMs;ii++) {
1080         PetscSection section;
1081         PetscInt Nf;
1082         DM dm = subDM[ii];
1083         PetscCall(DMGetLocalSection(dm, &section));
1084         PetscCall(PetscSectionGetNumFields(section, &Nf));
1085         jac->nBlocks += Nf;
1086 #if PCBJKOKKOS_VERBOSE_LEVEL <= 2
1087         if (ii==0) PetscCall(PetscInfo(pc,"%" PetscInt_FMT ") %" PetscInt_FMT " blocks (%" PetscInt_FMT " total)\n",ii,Nf,jac->nBlocks));
1088 #else
1089         PetscCall(PetscInfo(pc,"%" PetscInt_FMT ") %" PetscInt_FMT " blocks (%" PetscInt_FMT " total)\n",ii,Nf,jac->nBlocks));
1090 #endif
1091         jac->dm_Nf[ii] = Nf;
1092       }
1093       { // d_bid_eqOffset_k
1094         Kokkos::View<PetscInt*, Kokkos::LayoutRight, Kokkos::HostSpace> h_block_offsets("block_offsets", jac->nBlocks+1);
1095         PetscCall(DMCompositeGetAccessArray(pack, jac->vec_diag, nDMs, NULL, subX));
1096         h_block_offsets[0] = 0;
1097         jac->const_block_size = -1;
1098         for (PetscInt ii=0, idx = 0;ii<nDMs;ii++) {
1099           PetscInt nloc,nblk;
1100           PetscCall(VecGetSize(subX[ii],&nloc));
1101           nblk = nloc/jac->dm_Nf[ii];
1102           PetscCheck(nloc%jac->dm_Nf[ii] == 0,PetscObjectComm((PetscObject)pc),PETSC_ERR_USER,"nloc%%jac->dm_Nf[ii] (%" PetscInt_FMT ") != 0 DMs",nloc%jac->dm_Nf[ii]);
1103           for (PetscInt jj=0;jj<jac->dm_Nf[ii];jj++, idx++) {
1104             h_block_offsets[idx+1] = h_block_offsets[idx] + nblk;
1105 #if PCBJKOKKOS_VERBOSE_LEVEL <= 2
1106             if (idx==0) PetscCall(PetscInfo(pc,"\t%" PetscInt_FMT ") Add block with %" PetscInt_FMT " equations of %" PetscInt_FMT "\n",idx+1,nblk,jac->nBlocks));
1107 #else
1108             PetscCall(PetscInfo(pc,"\t%" PetscInt_FMT ") Add block with %" PetscInt_FMT " equations of %" PetscInt_FMT "\n",idx+1,nblk,jac->nBlocks));
1109 #endif
1110             if (jac->const_block_size == -1) jac->const_block_size = nblk;
1111             else if (jac->const_block_size > 0 && jac->const_block_size != nblk) jac->const_block_size = 0;
1112           }
1113         }
1114         PetscCall(DMCompositeRestoreAccessArray(pack, jac->vec_diag, jac->nBlocks, NULL, subX));
1115         PetscCall(PetscFree(subX));
1116         PetscCall(PetscFree(subDM));
1117         jac->d_bid_eqOffset_k = new Kokkos::View<PetscInt*, Kokkos::LayoutRight>(Kokkos::create_mirror(Kokkos::DefaultExecutionSpace::memory_space(),h_block_offsets));
1118         Kokkos::deep_copy (*jac->d_bid_eqOffset_k, h_block_offsets);
1119       }
1120     }
1121     { // get jac->d_idiag_k (PC setup),
1122       const PetscInt    *d_ai=aijkok->i_device_data(), *d_aj=aijkok->j_device_data();
1123       const PetscScalar *d_aa = aijkok->a_device_data();
1124       const PetscInt    conc = Kokkos::DefaultExecutionSpace().concurrency(), openmp = !!(conc < 1000), team_size = (openmp==0 && PCBJKOKKOS_VEC_SIZE != 1) ? PCBJKOKKOS_TEAM_SIZE : 1;
1125       PetscInt          *d_bid_eqOffset = jac->d_bid_eqOffset_k->data(), *r = jac->d_isrow_k->data(), *ic = jac->d_isicol_k->data();
1126       PetscScalar       *d_idiag = jac->d_idiag_k->data();
1127       Kokkos::parallel_for("Diag", Kokkos::TeamPolicy<>(jac->nBlocks, team_size, PCBJKOKKOS_VEC_SIZE), KOKKOS_LAMBDA (const team_member team) {
1128           const PetscInt blkID = team.league_rank();
1129           Kokkos::parallel_for
1130             (Kokkos::TeamThreadRange(team,d_bid_eqOffset[blkID],d_bid_eqOffset[blkID+1]),
1131              [=] (const int rowb) {
1132                const PetscInt    rowa = ic[rowb], ai = d_ai[rowa], *aj = d_aj + ai; // grab original data
1133                const PetscScalar *aa  = d_aa + ai;
1134                const PetscInt    nrow = d_ai[rowa + 1] - ai;
1135                int found;
1136                Kokkos::parallel_reduce
1137                  (Kokkos::ThreadVectorRange (team, nrow),
1138                   [=] (const int& j, int &count) {
1139                     const PetscInt colb = r[aj[j]];
1140                     if (colb==rowb) {
1141                       d_idiag[rowb] = 1./aa[j];
1142                       count++;
1143                     }}, found);
1144 #if defined(PETSC_USE_DEBUG) && !defined(PETSC_HAVE_SYCL)
1145                if (found!=1) Kokkos::single (Kokkos::PerThread (team), [=] () {printf("ERRORrow %d) found = %d\n",rowb,found);});
1146 #endif
1147              });
1148         });
1149     }
1150   }
1151   PetscFunctionReturn(0);
1152 }
1153 
1154 /* Default destroy, if it has never been setup */
1155 static PetscErrorCode PCReset_BJKOKKOS(PC pc)
1156 {
1157   PC_PCBJKOKKOS *jac = (PC_PCBJKOKKOS*)pc->data;
1158 
1159   PetscFunctionBegin;
1160   PetscCall(KSPDestroy(&jac->ksp));
1161   PetscCall(VecDestroy(&jac->vec_diag));
1162   if (jac->d_bid_eqOffset_k) delete jac->d_bid_eqOffset_k;
1163   if (jac->d_idiag_k) delete jac->d_idiag_k;
1164   if (jac->d_isrow_k) delete jac->d_isrow_k;
1165   if (jac->d_isicol_k) delete jac->d_isicol_k;
1166   jac->d_bid_eqOffset_k = NULL;
1167   jac->d_idiag_k = NULL;
1168   jac->d_isrow_k = NULL;
1169   jac->d_isicol_k = NULL;
1170   PetscCall(PetscObjectComposeFunction((PetscObject)pc,"PCBJKOKKOSGetKSP_C",NULL)); // not published now (causes configure errors)
1171   PetscCall(PetscObjectComposeFunction((PetscObject)pc,"PCBJKOKKOSSetKSP_C",NULL));
1172   PetscCall(PetscFree(jac->dm_Nf));
1173   jac->dm_Nf = NULL;
1174   if (jac->rowOffsets) delete jac->rowOffsets;
1175   if (jac->colIndices) delete jac->colIndices;
1176   if (jac->batch_b) delete jac->batch_b;
1177   if (jac->batch_x) delete jac->batch_x;
1178   if (jac->batch_values) delete jac->batch_values;
1179   jac->rowOffsets          = NULL;
1180   jac->colIndices          = NULL;
1181   jac->batch_b             = NULL;
1182   jac->batch_x             = NULL;
1183   jac->batch_values        = NULL;
1184 
1185   PetscFunctionReturn(0);
1186 }
1187 
1188 static PetscErrorCode PCDestroy_BJKOKKOS(PC pc)
1189 {
1190   PetscFunctionBegin;
1191   PetscCall(PCReset_BJKOKKOS(pc));
1192   PetscCall(PetscFree(pc->data));
1193   PetscFunctionReturn(0);
1194 }
1195 
1196 static PetscErrorCode PCView_BJKOKKOS(PC pc,PetscViewer viewer)
1197 {
1198   PC_PCBJKOKKOS *jac = (PC_PCBJKOKKOS*)pc->data;
1199   PetscBool      iascii;
1200 
1201   PetscFunctionBegin;
1202   if (!jac->ksp) PetscCall(PCBJKOKKOSCreateKSP_BJKOKKOS(pc));
1203   PetscCall(PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii));
1204   if (iascii) {
1205     PetscCall(PetscViewerASCIIPrintf(viewer,"  Batched device linear solver: Krylov (KSP) method with Jacobi preconditioning\n"));
1206     PetscCall(PetscViewerASCIIPrintf(viewer,"\t\tnwork = %" PetscInt_FMT ", rel tol = %e, abs tol = %e, div tol = %e, max it =%" PetscInt_FMT ", type = %s\n",jac->nwork,jac->ksp->rtol,
1207                                    jac->ksp->abstol, jac->ksp->divtol, jac->ksp->max_it,
1208                                    ((PetscObject)jac->ksp)->type_name));
1209   }
1210   PetscFunctionReturn(0);
1211 }
1212 
1213 static PetscErrorCode PCSetFromOptions_BJKOKKOS(PetscOptionItems *PetscOptionsObject,PC pc)
1214 {
1215   PetscFunctionBegin;
1216   PetscOptionsHeadBegin(PetscOptionsObject,"PC BJKOKKOS options");
1217   PetscOptionsHeadEnd();
1218   PetscFunctionReturn(0);
1219 }
1220 
1221 static PetscErrorCode  PCBJKOKKOSSetKSP_BJKOKKOS(PC pc,KSP ksp)
1222 {
1223   PC_PCBJKOKKOS *jac = (PC_PCBJKOKKOS*)pc->data;
1224 
1225   PetscFunctionBegin;
1226   PetscCall(PetscObjectReference((PetscObject)ksp));
1227   PetscCall(KSPDestroy(&jac->ksp));
1228   jac->ksp = ksp;
1229   PetscFunctionReturn(0);
1230 }
1231 
1232 /*@C
1233    PCBJKOKKOSSetKSP - Sets the KSP context for a KSP PC.
1234 
1235    Collective on PC
1236 
1237    Input Parameters:
1238 +  pc - the preconditioner context
1239 -  ksp - the KSP solver
1240 
1241    Notes:
1242    The PC and the KSP must have the same communicator
1243 
1244    Level: advanced
1245 
1246 @*/
1247 PetscErrorCode  PCBJKOKKOSSetKSP(PC pc,KSP ksp)
1248 {
1249   PetscFunctionBegin;
1250   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
1251   PetscValidHeaderSpecific(ksp,KSP_CLASSID,2);
1252   PetscCheckSameComm(pc,1,ksp,2);
1253   PetscTryMethod(pc,"PCBJKOKKOSSetKSP_C",(PC,KSP),(pc,ksp));
1254   PetscFunctionReturn(0);
1255 }
1256 
1257 static PetscErrorCode  PCBJKOKKOSGetKSP_BJKOKKOS(PC pc,KSP *ksp)
1258 {
1259   PC_PCBJKOKKOS *jac = (PC_PCBJKOKKOS*)pc->data;
1260 
1261   PetscFunctionBegin;
1262   if (!jac->ksp) PetscCall(PCBJKOKKOSCreateKSP_BJKOKKOS(pc));
1263   *ksp = jac->ksp;
1264   PetscFunctionReturn(0);
1265 }
1266 
1267 /*@C
1268    PCBJKOKKOSGetKSP - Gets the KSP context for a KSP PC.
1269 
1270    Not Collective but KSP returned is parallel if PC was parallel
1271 
1272    Input Parameter:
1273 .  pc - the preconditioner context
1274 
1275    Output Parameters:
1276 .  ksp - the KSP solver
1277 
1278    Notes:
1279    You must call KSPSetUp() before calling PCBJKOKKOSGetKSP().
1280 
1281    If the PC is not a PCBJKOKKOS object it raises an error
1282 
1283    Level: advanced
1284 
1285 @*/
1286 PetscErrorCode  PCBJKOKKOSGetKSP(PC pc,KSP *ksp)
1287 {
1288   PetscFunctionBegin;
1289   PetscValidHeaderSpecific(pc,PC_CLASSID,1);
1290   PetscValidPointer(ksp,2);
1291   PetscUseMethod(pc,"PCBJKOKKOSGetKSP_C",(PC,KSP*),(pc,ksp));
1292   PetscFunctionReturn(0);
1293 }
1294 
1295 static PetscErrorCode PCPostSolve_BJKOKKOS(PC pc,KSP ksp,Vec b,Vec x)
1296 {
1297   PC_PCBJKOKKOS *jac = (PC_PCBJKOKKOS*)pc->data;
1298 
1299   PetscFunctionBegin;
1300   ksp->its = jac->max_nits;
1301   PetscFunctionReturn(0);
1302 }
1303 
1304 /* ----------------------------------------------------------------------------------*/
1305 
1306 /*MC
1307      PCBJKOKKOS -  Defines a preconditioner that applies a Krylov solver and preconditioner to the blocks in a AIJASeq matrix on the GPU.
1308 
1309    Options Database Key:
1310 .     -pc_bjkokkos_ - options prefix with ksp options
1311 
1312    Level: intermediate
1313 
1314    Notes:
1315     For use with -ksp_type preonly to bypass any CPU work
1316 
1317    Developer Notes:
1318 
1319 .seealso: `PCCreate()`, `PCSetType()`, `PCType`, `PC`,
1320           `PCSHELL`, `PCCOMPOSITE`, `PCSetUseAmat()`, `PCBJKOKKOSGetKSP()`
1321 
1322 M*/
1323 
1324 PETSC_EXTERN PetscErrorCode PCCreate_BJKOKKOS(PC pc)
1325 {
1326   PC_PCBJKOKKOS *jac;
1327 
1328   PetscFunctionBegin;
1329   PetscCall(PetscNewLog(pc,&jac));
1330   pc->data = (void*)jac;
1331 
1332   jac->ksp              = NULL;
1333   jac->vec_diag         = NULL;
1334   jac->d_bid_eqOffset_k = NULL;
1335   jac->d_idiag_k        = NULL;
1336   jac->d_isrow_k        = NULL;
1337   jac->d_isicol_k       = NULL;
1338   jac->nBlocks          = 1;
1339   jac->max_nits         = 0;
1340 
1341   PetscCall(PetscMemzero(pc->ops,sizeof(struct _PCOps)));
1342   pc->ops->apply           = PCApply_BJKOKKOS;
1343   pc->ops->applytranspose  = NULL;
1344   pc->ops->setup           = PCSetUp_BJKOKKOS;
1345   pc->ops->reset           = PCReset_BJKOKKOS;
1346   pc->ops->destroy         = PCDestroy_BJKOKKOS;
1347   pc->ops->setfromoptions  = PCSetFromOptions_BJKOKKOS;
1348   pc->ops->view            = PCView_BJKOKKOS;
1349   pc->ops->postsolve       = PCPostSolve_BJKOKKOS;
1350 
1351   jac->rowOffsets          = NULL;
1352   jac->colIndices          = NULL;
1353   jac->batch_b             = NULL;
1354   jac->batch_x             = NULL;
1355   jac->batch_values        = NULL;
1356 
1357   PetscCall(PetscObjectComposeFunction((PetscObject)pc,"PCBJKOKKOSGetKSP_C",PCBJKOKKOSGetKSP_BJKOKKOS));
1358   PetscCall(PetscObjectComposeFunction((PetscObject)pc,"PCBJKOKKOSSetKSP_C",PCBJKOKKOSSetKSP_BJKOKKOS));
1359   PetscFunctionReturn(0);
1360 }
1361