301 lines
		
	
	
		
			9.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			301 lines
		
	
	
		
			9.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * Copyright (c) 2003, 2007-14 Matteo Frigo | ||
|  |  * Copyright (c) 2003, 2007-14 Massachusetts Institute of Technology | ||
|  |  * | ||
|  |  * This program is free software; you can redistribute it and/or modify | ||
|  |  * it under the terms of the GNU General Public License as published by | ||
|  |  * the Free Software Foundation; either version 2 of the License, or | ||
|  |  * (at your option) any later version. | ||
|  |  * | ||
|  |  * This program is distributed in the hope that it will be useful, | ||
|  |  * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
|  |  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | ||
|  |  * GNU General Public License for more details. | ||
|  |  * | ||
|  |  * You should have received a copy of the GNU General Public License | ||
|  |  * along with this program; if not, write to the Free Software | ||
|  |  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA | ||
|  |  * | ||
|  |  */ | ||
|  | 
 | ||
|  | /* Recursive "radix-r" distributed transpose, which breaks a transpose
 | ||
|  |    over p processes into p/r transposes over r processes plus r | ||
|  |    transposes over p/r processes.  If performed recursively, this | ||
|  |    produces a total of O(p log p) messages vs. O(p^2) messages for a | ||
|  |    direct approach. | ||
|  | 
 | ||
|  |    However, this is not necessarily an improvement.  The total size of | ||
|  |    all the messages is actually increased from O(N) to O(N log p) | ||
|  |    where N is the total data size.  Also, the amount of local data | ||
|  |    rearrangement is increased.  So, it's not clear, a priori, what the | ||
|  |    best algorithm will be, and we'll leave it to the planner.  (In | ||
|  |    theory and practice, it looks like this becomes advantageous for | ||
|  |    large p, in the limit where the message sizes are small and | ||
|  |    latency-dominated.) | ||
|  | */ | ||
|  | 
 | ||
|  | #include "mpi-transpose.h"
 | ||
|  | #include <string.h>
 | ||
|  | 
 | ||
|  | typedef struct { | ||
|  |      solver super; | ||
|  |      int (*radix)(int np); | ||
|  |      const char *nam; | ||
|  |      int preserve_input; /* preserve input even if DESTROY_INPUT was passed */ | ||
|  | } S; | ||
|  | 
 | ||
|  | typedef struct { | ||
|  |      plan_mpi_transpose super; | ||
|  | 
 | ||
|  |      plan *cld1, *cldtr, *cldtm; | ||
|  |      int preserve_input; | ||
|  | 
 | ||
|  |      int r; /* "radix" */ | ||
|  |      const char *nam; | ||
|  | } P; | ||
|  | 
 | ||
|  | static void apply(const plan *ego_, R *I, R *O) | ||
|  | { | ||
|  |      const P *ego = (const P *) ego_; | ||
|  |      plan_rdft *cld1, *cldtr, *cldtm; | ||
|  | 
 | ||
|  |      cld1 = (plan_rdft *) ego->cld1; | ||
|  |      if (cld1) cld1->apply((plan *) cld1, I, O); | ||
|  | 
 | ||
|  |      if (ego->preserve_input) I = O; | ||
|  | 
 | ||
|  |      cldtr = (plan_rdft *) ego->cldtr; | ||
|  |      if (cldtr) cldtr->apply((plan *) cldtr, O, I); | ||
|  | 
 | ||
|  |      cldtm = (plan_rdft *) ego->cldtm; | ||
|  |      if (cldtm) cldtm->apply((plan *) cldtm, I, O); | ||
|  | } | ||
|  | 
 | ||
|  | static int radix_sqrt(int np) | ||
|  | { | ||
|  |      int r; | ||
|  |      for (r = (int) (X(isqrt)(np)); np % r != 0; ++r) | ||
|  | 	  ; | ||
|  |      return r; | ||
|  | } | ||
|  | 
 | ||
|  | static int radix_first(int np) | ||
|  | { | ||
|  |      int r = (int) (X(first_divisor)(np)); | ||
|  |      return (r >= (int) (X(isqrt)(np)) ? 0 : r); | ||
|  | } | ||
|  | 
 | ||
|  | /* the local allocated space on process pe required for the given transpose
 | ||
|  |    dimensions and block sizes */ | ||
|  | static INT transpose_space(INT nx, INT ny, INT block, INT tblock, int pe) | ||
|  | { | ||
|  |      return X(imax)(XM(block)(nx, block, pe) * ny, | ||
|  | 		    nx * XM(block)(ny, tblock, pe)); | ||
|  | } | ||
|  | 
 | ||
|  | /* check whether the recursive transposes fit within the space
 | ||
|  |    that must have been allocated on each process for this transpose; | ||
|  |    this must be modified if the subdivision in mkplan is changed! */ | ||
|  | static int enough_space(INT nx, INT ny, INT block, INT tblock, | ||
|  | 			int r, int n_pes) | ||
|  | { | ||
|  |      int pe; | ||
|  |      int m = n_pes / r; | ||
|  |      for (pe = 0; pe < n_pes; ++pe) { | ||
|  | 	  INT space = transpose_space(nx, ny, block, tblock, pe); | ||
|  | 	  INT b1 = XM(block)(nx, r * block, pe / r); | ||
|  | 	  INT b2 = XM(block)(ny, m * tblock, pe % r); | ||
|  | 	  if (transpose_space(b1, ny, block, m*tblock, pe % r) > space | ||
|  | 	      || transpose_space(nx, b2, r*block, tblock, pe / r) > space) | ||
|  | 	       return 0; | ||
|  |      } | ||
|  |      return 1; | ||
|  | } | ||
|  | 
 | ||
|  | /* In theory, transpose-recurse becomes advantageous for message sizes
 | ||
|  |    below some minimum, assuming that the time is dominated by | ||
|  |    communications.  In practice, we want to constrain the minimum | ||
|  |    message size for transpose-recurse to keep the planning time down. | ||
|  |    I've set this conservatively according to some simple experiments | ||
|  |    on a Cray XT3 where the crossover message size was 128, although on | ||
|  |    a larger-latency machine the crossover will be larger. */ | ||
|  | #define SMALL_MESSAGE 2048
 | ||
|  | 
 | ||
|  | static int applicable(const S *ego, const problem *p_, | ||
|  | 		      const planner *plnr, int *r) | ||
|  | { | ||
|  |      const problem_mpi_transpose *p = (const problem_mpi_transpose *) p_; | ||
|  |      int n_pes; | ||
|  |      MPI_Comm_size(p->comm, &n_pes); | ||
|  |      return (1 | ||
|  | 	     && p->tblock * n_pes == p->ny | ||
|  | 	     && (!ego->preserve_input || (!NO_DESTROY_INPUTP(plnr) | ||
|  |                                           && p->I != p->O)) | ||
|  | 	     && (*r = ego->radix(n_pes)) && *r < n_pes && *r > 1 | ||
|  | 	     && enough_space(p->nx, p->ny, p->block, p->tblock, *r, n_pes) | ||
|  | 	     && (!CONSERVE_MEMORYP(plnr) || *r > 8 | ||
|  | 		 || !X(toobig)((p->nx * (p->ny / n_pes) * p->vn) / *r)) | ||
|  | 	     && (!NO_SLOWP(plnr) ||  | ||
|  | 		 (p->nx * (p->ny / n_pes) * p->vn) / n_pes <= SMALL_MESSAGE) | ||
|  | 	     && ONLY_TRANSPOSEDP(p->flags) | ||
|  | 	  ); | ||
|  | } | ||
|  | 
 | ||
|  | static void awake(plan *ego_, enum wakefulness wakefulness) | ||
|  | { | ||
|  |      P *ego = (P *) ego_; | ||
|  |      X(plan_awake)(ego->cld1, wakefulness); | ||
|  |      X(plan_awake)(ego->cldtr, wakefulness); | ||
|  |      X(plan_awake)(ego->cldtm, wakefulness); | ||
|  | } | ||
|  | 
 | ||
|  | static void destroy(plan *ego_) | ||
|  | { | ||
|  |      P *ego = (P *) ego_; | ||
|  |      X(plan_destroy_internal)(ego->cldtm); | ||
|  |      X(plan_destroy_internal)(ego->cldtr); | ||
|  |      X(plan_destroy_internal)(ego->cld1); | ||
|  | } | ||
|  | 
 | ||
|  | static void print(const plan *ego_, printer *p) | ||
|  | { | ||
|  |      const P *ego = (const P *) ego_; | ||
|  |      p->print(p, "(mpi-transpose-recurse/%s/%d%s%(%p%)%(%p%)%(%p%))", | ||
|  | 	      ego->nam, ego->r, ego->preserve_input==2 ?"/p":"", | ||
|  | 	      ego->cld1, ego->cldtr, ego->cldtm); | ||
|  | } | ||
|  | 
 | ||
|  | static plan *mkplan(const solver *ego_, const problem *p_, planner *plnr) | ||
|  | { | ||
|  |      const S *ego = (const S *) ego_; | ||
|  |      const problem_mpi_transpose *p; | ||
|  |      P *pln; | ||
|  |      plan *cld1 = 0, *cldtr = 0, *cldtm = 0; | ||
|  |      R *I, *O; | ||
|  |      int me, np, r, m; | ||
|  |      INT b; | ||
|  |      MPI_Comm comm2; | ||
|  |      static const plan_adt padt = { | ||
|  |           XM(transpose_solve), awake, print, destroy | ||
|  |      }; | ||
|  | 
 | ||
|  |      UNUSED(ego); | ||
|  | 
 | ||
|  |      if (!applicable(ego, p_, plnr, &r)) | ||
|  |           return (plan *) 0; | ||
|  | 
 | ||
|  |      p = (const problem_mpi_transpose *) p_; | ||
|  | 
 | ||
|  |      MPI_Comm_size(p->comm, &np); | ||
|  |      MPI_Comm_rank(p->comm, &me); | ||
|  |      m = np / r; | ||
|  |      A(r * m == np); | ||
|  | 
 | ||
|  |      I = p->I; O = p->O; | ||
|  | 
 | ||
|  |      b = XM(block)(p->nx, p->block, me); | ||
|  |      A(p->tblock * np == p->ny); /* this is currently required for cld1 */ | ||
|  |      if (p->flags & TRANSPOSED_IN) {  | ||
|  |           /* m x r x (bt x b x vn) -> r x m x (bt x b x vn) */ | ||
|  | 	  INT vn = p->vn * b * p->tblock; | ||
|  | 	  cld1 = X(mkplan_f_d)(plnr, | ||
|  |                                X(mkproblem_rdft_0_d)(X(mktensor_3d) | ||
|  | 						     (m, r*vn, vn, | ||
|  | 						      r, vn, m*vn, | ||
|  | 						      vn, 1, 1), | ||
|  |                                                      I, O), | ||
|  |                                0, 0, NO_SLOW); | ||
|  |      } | ||
|  |      else if (I != O) { /* combine cld1 with TRANSPOSED_IN permutation */ | ||
|  |           /* b x m x r x bt x vn -> r x m x bt x b x vn */ | ||
|  | 	  INT vn = p->vn; | ||
|  | 	  INT bt = p->tblock; | ||
|  | 	  cld1 = X(mkplan_f_d)(plnr, | ||
|  |                                X(mkproblem_rdft_0_d)(X(mktensor_5d) | ||
|  | 						     (b, m*r*bt*vn, vn, | ||
|  | 						      m, r*bt*vn, bt*b*vn, | ||
|  | 						      r, bt*vn, m*bt*b*vn, | ||
|  | 						      bt, vn, b*vn, | ||
|  | 						      vn, 1, 1), | ||
|  |                                                      I, O), | ||
|  |                                0, 0, NO_SLOW); | ||
|  |      } | ||
|  |      else { /* TRANSPOSED_IN permutation must be separate for in-place */ | ||
|  | 	  /* b x (m x r) x bt x vn -> b x (r x m) x bt x vn */ | ||
|  | 	  INT vn = p->vn * p->tblock; | ||
|  | 	  cld1 = X(mkplan_f_d)(plnr, | ||
|  |                                X(mkproblem_rdft_0_d)(X(mktensor_4d) | ||
|  | 						     (m, r*vn, vn, | ||
|  | 						      r, vn, m*vn, | ||
|  | 						      vn, 1, 1, | ||
|  | 						      b, np*vn, np*vn), | ||
|  |                                                      I, O), | ||
|  |                                0, 0, NO_SLOW); | ||
|  |      } | ||
|  |      if (XM(any_true)(!cld1, p->comm)) goto nada; | ||
|  | 
 | ||
|  |      if (ego->preserve_input || NO_DESTROY_INPUTP(plnr)) I = O; | ||
|  | 
 | ||
|  |      b = XM(block)(p->nx, r * p->block, me / r); | ||
|  |      MPI_Comm_split(p->comm, me / r, me, &comm2); | ||
|  |      if (b) | ||
|  | 	  cldtr = X(mkplan_d)(plnr, XM(mkproblem_transpose) | ||
|  | 			      (b, p->ny, p->vn, | ||
|  | 			       O, I, p->block, m * p->tblock, comm2,  | ||
|  | 			       p->I != p->O | ||
|  | 			       ? TRANSPOSED_IN : (p->flags & TRANSPOSED_IN))); | ||
|  |      MPI_Comm_free(&comm2); | ||
|  |      if (XM(any_true)(b && !cldtr, p->comm)) goto nada; | ||
|  |       | ||
|  |      b = XM(block)(p->ny, m * p->tblock, me % r); | ||
|  |      MPI_Comm_split(p->comm, me % r, me, &comm2); | ||
|  |      if (b) | ||
|  | 	  cldtm = X(mkplan_d)(plnr, XM(mkproblem_transpose) | ||
|  | 			      (p->nx, b, p->vn, | ||
|  | 			       I, O, r * p->block, p->tblock, comm2,  | ||
|  | 			       TRANSPOSED_IN | (p->flags & TRANSPOSED_OUT))); | ||
|  |      MPI_Comm_free(&comm2); | ||
|  |      if (XM(any_true)(b && !cldtm, p->comm)) goto nada; | ||
|  | 
 | ||
|  |      pln = MKPLAN_MPI_TRANSPOSE(P, &padt, apply); | ||
|  | 
 | ||
|  |      pln->cld1 = cld1; | ||
|  |      pln->cldtr = cldtr; | ||
|  |      pln->cldtm = cldtm; | ||
|  |      pln->preserve_input = ego->preserve_input ? 2 : NO_DESTROY_INPUTP(plnr); | ||
|  |      pln->r = r; | ||
|  |      pln->nam = ego->nam; | ||
|  | 
 | ||
|  |      pln->super.super.ops = cld1->ops; | ||
|  |      if (cldtr) X(ops_add2)(&cldtr->ops, &pln->super.super.ops); | ||
|  |      if (cldtm) X(ops_add2)(&cldtm->ops, &pln->super.super.ops); | ||
|  | 
 | ||
|  |      return &(pln->super.super); | ||
|  | 
 | ||
|  |  nada: | ||
|  |      X(plan_destroy_internal)(cldtm); | ||
|  |      X(plan_destroy_internal)(cldtr); | ||
|  |      X(plan_destroy_internal)(cld1); | ||
|  |      return (plan *) 0; | ||
|  | } | ||
|  | 
 | ||
|  | static solver *mksolver(int preserve_input, | ||
|  | 			int (*radix)(int np), const char *nam) | ||
|  | { | ||
|  |      static const solver_adt sadt = { PROBLEM_MPI_TRANSPOSE, mkplan, 0 }; | ||
|  |      S *slv = MKSOLVER(S, &sadt); | ||
|  |      slv->preserve_input = preserve_input; | ||
|  |      slv->radix = radix; | ||
|  |      slv->nam = nam; | ||
|  |      return &(slv->super); | ||
|  | } | ||
|  | 
 | ||
|  | void XM(transpose_recurse_register)(planner *p) | ||
|  | { | ||
|  |      int preserve_input; | ||
|  |      for (preserve_input = 0; preserve_input <= 1; ++preserve_input) { | ||
|  | 	  REGISTER_SOLVER(p, mksolver(preserve_input, radix_sqrt, "sqrt")); | ||
|  | 	  REGISTER_SOLVER(p, mksolver(preserve_input, radix_first, "first")); | ||
|  |      } | ||
|  | } |