X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/076aada113aa0566c059211416cd9214a54d763d..8293a833f9c68986f8bd174d5bf3d04eb62918d7:/src/smpi/colls/reduce_scatter-mpich.c

diff --git a/src/smpi/colls/reduce_scatter-mpich.c b/src/smpi/colls/reduce_scatter-mpich.c
new file mode 100644
index 0000000000..77eaef5bf8
--- /dev/null
+++ b/src/smpi/colls/reduce_scatter-mpich.c
@@ -0,0 +1,493 @@
+#include "colls_private.h"
+#define MPIR_REDUCE_SCATTER_TAG 222
+
+static inline int MPIU_Mirror_permutation(unsigned int x, int bits)
+{
+    /* a mask for the high order bits that should be copied as-is */
+    int high_mask = ~((0x1 << bits) - 1);
+    int retval = x & high_mask;
+    int i;
+
+    for (i = 0; i < bits; ++i) {
+        unsigned int bitval = (x & (0x1 << i)) >> i; /* 0x1 or 0x0 */
+        retval |= bitval << ((bits - i) - 1);
+    }
+
+    return retval;
+}
+
+
+int smpi_coll_tuned_reduce_scatter_mpich_pair(void *sendbuf, void *recvbuf, int recvcounts[],
+                              MPI_Datatype datatype, MPI_Op op, MPI_Comm comm)
+{
+    int   rank, comm_size, i;
+    MPI_Aint extent, true_extent, true_lb; 
+    int  *disps;
+    void *tmp_recvbuf;
+    int mpi_errno = MPI_SUCCESS;
+    int type_size, total_count, nbytes, dst, src;
+    int is_commutative;
+    comm_size = smpi_comm_size(comm);
+    rank = smpi_comm_rank(comm);
+
+    extent =smpi_datatype_get_extent(datatype);
+    smpi_datatype_extent(datatype, &true_lb, &true_extent);
+    
+    if (smpi_op_is_commute(op)) {
+        is_commutative = 1;
+    }
+
+    disps = (int*)xbt_malloc( comm_size * sizeof(int));
+
+    total_count = 0;
+    for (i=0; i<comm_size; i++) {
+        disps[i] = total_count;
+        total_count += recvcounts[i];
+    }
+    
+    if (total_count == 0) {
+        return MPI_ERR_COUNT;
+    }
+
+    type_size= smpi_datatype_size(datatype);
+    nbytes = total_count * type_size;
+    
+
+        if (sendbuf != MPI_IN_PLACE) {
+            /* copy local data into recvbuf */
+            smpi_datatype_copy(((char *)sendbuf+disps[rank]*extent),
+                                       recvcounts[rank], datatype, recvbuf,
+                                       recvcounts[rank], datatype);
+        }
+        
+        /* allocate temporary buffer to store incoming data */
+        tmp_recvbuf = (void*)xbt_malloc(recvcounts[rank]*(max(true_extent,extent))+1);
+        /* adjust for potential negative lower bound in datatype */
+        tmp_recvbuf = (void *)((char*)tmp_recvbuf - true_lb);
+        
+        for (i=1; i<comm_size; i++) {
+            src = (rank - i + comm_size) % comm_size;
+            dst = (rank + i) % comm_size;
+            
+            /* send the data that dst needs. recv data that this process
+               needs from src into tmp_recvbuf */
+            if (sendbuf != MPI_IN_PLACE) 
+                smpi_mpi_sendrecv(((char *)sendbuf+disps[dst]*extent), 
+                                             recvcounts[dst], datatype, dst,
+                                             MPIR_REDUCE_SCATTER_TAG, tmp_recvbuf,
+                                             recvcounts[rank], datatype, src,
+                                             MPIR_REDUCE_SCATTER_TAG, comm,
+                                             MPI_STATUS_IGNORE);
+            else
+                smpi_mpi_sendrecv(((char *)recvbuf+disps[dst]*extent), 
+                                             recvcounts[dst], datatype, dst,
+                                             MPIR_REDUCE_SCATTER_TAG, tmp_recvbuf,
+                                             recvcounts[rank], datatype, src,
+                                             MPIR_REDUCE_SCATTER_TAG, comm,
+                                             MPI_STATUS_IGNORE);
+            
+            if (is_commutative || (src < rank)) {
+                if (sendbuf != MPI_IN_PLACE) {
+		     smpi_op_apply( op,
+			                          tmp_recvbuf, recvbuf, &recvcounts[rank],
+                               &datatype); 
+                }
+                else {
+		    smpi_op_apply(op, 
+			tmp_recvbuf, ((char *)recvbuf+disps[rank]*extent), 
+			&recvcounts[rank], &datatype);
+                    /* we can't store the result at the beginning of
+                       recvbuf right here because there is useful data
+                       there that other process/processes need. at the
+                       end, we will copy back the result to the
+                       beginning of recvbuf. */
+                }
+            }
+            else {
+                if (sendbuf != MPI_IN_PLACE) {
+		    smpi_op_apply(op, 
+		       recvbuf, tmp_recvbuf, &recvcounts[rank], &datatype);
+                    /* copy result back into recvbuf */
+                    mpi_errno = smpi_datatype_copy(tmp_recvbuf, recvcounts[rank],
+                                               datatype, recvbuf,
+                                               recvcounts[rank], datatype);
+                    if (mpi_errno) return(mpi_errno);
+                }
+                else {
+		    smpi_op_apply(op, 
+                        ((char *)recvbuf+disps[rank]*extent),
+			tmp_recvbuf, &recvcounts[rank], &datatype);
+                    /* copy result back into recvbuf */
+                    mpi_errno = smpi_datatype_copy(tmp_recvbuf, recvcounts[rank],
+                                               datatype, 
+                                               ((char *)recvbuf +
+                                                disps[rank]*extent), 
+                                               recvcounts[rank], datatype);
+                    if (mpi_errno) return(mpi_errno);
+                }
+            }
+        }
+        
+        /* if MPI_IN_PLACE, move output data to the beginning of
+           recvbuf. already done for rank 0. */
+        if ((sendbuf == MPI_IN_PLACE) && (rank != 0)) {
+            mpi_errno = smpi_datatype_copy(((char *)recvbuf +
+                                        disps[rank]*extent),  
+                                       recvcounts[rank], datatype,
+                                       recvbuf, 
+                                       recvcounts[rank], datatype );
+            if (mpi_errno) return(mpi_errno);
+        }
+    
+return MPI_SUCCESS;
+}
+    
+
+int smpi_coll_tuned_reduce_scatter_mpich_noncomm(void *sendbuf, void *recvbuf, int recvcounts[],
+                              MPI_Datatype datatype, MPI_Op op, MPI_Comm comm)
+{
+    int mpi_errno = MPI_SUCCESS;
+    int comm_size = smpi_comm_size(comm) ;
+    int rank = smpi_comm_rank(comm);
+    int pof2;
+    int log2_comm_size;
+    int i, k;
+    int recv_offset, send_offset;
+    int block_size, total_count, size;
+    MPI_Aint true_extent, true_lb;
+    int buf0_was_inout;
+    void *tmp_buf0;
+    void *tmp_buf1;
+    void *result_ptr;
+
+    smpi_datatype_extent(datatype, &true_lb, &true_extent);
+
+    pof2 = 1;
+    log2_comm_size = 0;
+    while (pof2 < comm_size) {
+        pof2 <<= 1;
+        ++log2_comm_size;
+    }
+
+    /* begin error checking */
+    xbt_assert(pof2 == comm_size); /* FIXME this version only works for power of 2 procs */
+
+    for (i = 0; i < (comm_size - 1); ++i) {
+        xbt_assert(recvcounts[i] == recvcounts[i+1]);
+    }
+    /* end error checking */
+
+    /* size of a block (count of datatype per block, NOT bytes per block) */
+    block_size = recvcounts[0];
+    total_count = block_size * comm_size;
+
+    tmp_buf0=( void *)xbt_malloc( true_extent * total_count);
+    tmp_buf1=( void *)xbt_malloc( true_extent * total_count);
+    /* adjust for potential negative lower bound in datatype */
+    tmp_buf0 = (void *)((char*)tmp_buf0 - true_lb);
+    tmp_buf1 = (void *)((char*)tmp_buf1 - true_lb);
+
+    /* Copy our send data to tmp_buf0.  We do this one block at a time and
+       permute the blocks as we go according to the mirror permutation. */
+    for (i = 0; i < comm_size; ++i) {
+        mpi_errno = smpi_datatype_copy((char *)(sendbuf == MPI_IN_PLACE ? recvbuf : sendbuf) + (i * true_extent * block_size), block_size, datatype,
+                                   (char *)tmp_buf0 + (MPIU_Mirror_permutation(i, log2_comm_size) * true_extent * block_size), block_size, datatype);
+        if (mpi_errno) return(mpi_errno);
+    }
+    buf0_was_inout = 1;
+
+    send_offset = 0;
+    recv_offset = 0;
+    size = total_count;
+    for (k = 0; k < log2_comm_size; ++k) {
+        /* use a double-buffering scheme to avoid local copies */
+        char *incoming_data = (buf0_was_inout ? tmp_buf1 : tmp_buf0);
+        char *outgoing_data = (buf0_was_inout ? tmp_buf0 : tmp_buf1);
+        int peer = rank ^ (0x1 << k);
+        size /= 2;
+
+        if (rank > peer) {
+            /* we have the higher rank: send top half, recv bottom half */
+            recv_offset += size;
+        }
+        else {
+            /* we have the lower rank: recv top half, send bottom half */
+            send_offset += size;
+        }
+
+        smpi_mpi_sendrecv(outgoing_data + send_offset*true_extent,
+                                     size, datatype, peer, MPIR_REDUCE_SCATTER_TAG,
+                                     incoming_data + recv_offset*true_extent,
+                                     size, datatype, peer, MPIR_REDUCE_SCATTER_TAG,
+                                     comm, MPI_STATUS_IGNORE);
+        /* always perform the reduction at recv_offset, the data at send_offset
+           is now our peer's responsibility */
+        if (rank > peer) {
+            /* higher ranked value so need to call op(received_data, my_data) */
+            smpi_op_apply(op, 
+                   incoming_data + recv_offset*true_extent,
+                     outgoing_data + recv_offset*true_extent,
+                     &size, &datatype );
+            buf0_was_inout = buf0_was_inout;
+        }
+        else {
+            /* lower ranked value so need to call op(my_data, received_data) */
+	    smpi_op_apply( op,
+		     outgoing_data + recv_offset*true_extent,
+                     incoming_data + recv_offset*true_extent,
+                     &size, &datatype);
+            buf0_was_inout = !buf0_was_inout;
+        }
+
+        /* the next round of send/recv needs to happen within the block (of size
+           "size") that we just received and reduced */
+        send_offset = recv_offset;
+    }
+
+    xbt_assert(size == recvcounts[rank]);
+
+    /* copy the reduced data to the recvbuf */
+    result_ptr = (char *)(buf0_was_inout ? tmp_buf0 : tmp_buf1) + recv_offset * true_extent;
+    mpi_errno = smpi_datatype_copy(result_ptr, size, datatype,
+                               recvbuf, size, datatype);
+    if (mpi_errno) return(mpi_errno);
+    return MPI_SUCCESS;
+}
+
+
+
+int smpi_coll_tuned_reduce_scatter_mpich_rdb(void *sendbuf, void *recvbuf, int recvcounts[],
+                              MPI_Datatype datatype, MPI_Op op, MPI_Comm comm)
+{
+    int   rank, comm_size, i;
+    MPI_Aint extent, true_extent, true_lb; 
+    int  *disps;
+    void *tmp_recvbuf, *tmp_results;
+    int mpi_errno = MPI_SUCCESS;
+    int type_size, dis[2], blklens[2], total_count, nbytes, dst;
+    int mask, dst_tree_root, my_tree_root, j, k;
+    int received;
+    MPI_Datatype sendtype, recvtype;
+    int nprocs_completed, tmp_mask, tree_root, is_commutative;
+    comm_size = smpi_comm_size(comm);
+    rank = smpi_comm_rank(comm);
+
+    extent =smpi_datatype_get_extent(datatype);
+    smpi_datatype_extent(datatype, &true_lb, &true_extent);
+    
+    if (smpi_op_is_commute(op)) {
+        is_commutative = 1;
+    }
+
+    disps = (int*)xbt_malloc( comm_size * sizeof(int));
+
+    total_count = 0;
+    for (i=0; i<comm_size; i++) {
+        disps[i] = total_count;
+        total_count += recvcounts[i];
+    }
+    
+    type_size= smpi_datatype_size(datatype);
+    nbytes = total_count * type_size;
+    
+
+            /* noncommutative and (non-pof2 or block irregular), use recursive doubling. */
+
+            /* need to allocate temporary buffer to receive incoming data*/
+            tmp_recvbuf= (void *) xbt_malloc( total_count*(max(true_extent,extent)));
+            /* adjust for potential negative lower bound in datatype */
+            tmp_recvbuf = (void *)((char*)tmp_recvbuf - true_lb);
+
+            /* need to allocate another temporary buffer to accumulate
+               results */
+            tmp_results = (void *)xbt_malloc( total_count*(max(true_extent,extent)));
+            /* adjust for potential negative lower bound in datatype */
+            tmp_results = (void *)((char*)tmp_results - true_lb);
+
+            /* copy sendbuf into tmp_results */
+            if (sendbuf != MPI_IN_PLACE)
+                mpi_errno = smpi_datatype_copy(sendbuf, total_count, datatype,
+                                           tmp_results, total_count, datatype);
+            else
+                mpi_errno = smpi_datatype_copy(recvbuf, total_count, datatype,
+                                           tmp_results, total_count, datatype);
+
+            if (mpi_errno) return(mpi_errno);
+
+            mask = 0x1;
+            i = 0;
+            while (mask < comm_size) {
+                dst = rank ^ mask;
+
+                dst_tree_root = dst >> i;
+                dst_tree_root <<= i;
+
+                my_tree_root = rank >> i;
+                my_tree_root <<= i;
+
+                /* At step 1, processes exchange (n-n/p) amount of
+                   data; at step 2, (n-2n/p) amount of data; at step 3, (n-4n/p)
+                   amount of data, and so forth. We use derived datatypes for this.
+
+                   At each step, a process does not need to send data
+                   indexed from my_tree_root to
+                   my_tree_root+mask-1. Similarly, a process won't receive
+                   data indexed from dst_tree_root to dst_tree_root+mask-1. */
+
+                /* calculate sendtype */
+                blklens[0] = blklens[1] = 0;
+                for (j=0; j<my_tree_root; j++)
+                    blklens[0] += recvcounts[j];
+                for (j=my_tree_root+mask; j<comm_size; j++)
+                    blklens[1] += recvcounts[j];
+
+                dis[0] = 0;
+                dis[1] = blklens[0];
+                for (j=my_tree_root; (j<my_tree_root+mask) && (j<comm_size); j++)
+                    dis[1] += recvcounts[j];
+
+                mpi_errno = smpi_datatype_indexed(2, blklens, dis, datatype, &sendtype);
+                if (mpi_errno) return(mpi_errno);
+                
+                smpi_datatype_commit(&sendtype);
+
+                /* calculate recvtype */
+                blklens[0] = blklens[1] = 0;
+                for (j=0; j<dst_tree_root && j<comm_size; j++)
+                    blklens[0] += recvcounts[j];
+                for (j=dst_tree_root+mask; j<comm_size; j++)
+                    blklens[1] += recvcounts[j];
+
+                dis[0] = 0;
+                dis[1] = blklens[0];
+                for (j=dst_tree_root; (j<dst_tree_root+mask) && (j<comm_size); j++)
+                    dis[1] += recvcounts[j];
+
+                mpi_errno = smpi_datatype_indexed(2, blklens, dis, datatype, &recvtype);
+                if (mpi_errno) return(mpi_errno);
+                
+                smpi_datatype_commit(&recvtype);
+
+                received = 0;
+                if (dst < comm_size) {
+                    /* tmp_results contains data to be sent in each step. Data is
+                       received in tmp_recvbuf and then accumulated into
+                       tmp_results. accumulation is done later below.   */ 
+
+                    smpi_mpi_sendrecv(tmp_results, 1, sendtype, dst,
+                                                 MPIR_REDUCE_SCATTER_TAG, 
+                                                 tmp_recvbuf, 1, recvtype, dst,
+                                                 MPIR_REDUCE_SCATTER_TAG, comm,
+                                                 MPI_STATUS_IGNORE);
+                    received = 1;
+                }
+
+                /* if some processes in this process's subtree in this step
+                   did not have any destination process to communicate with
+                   because of non-power-of-two, we need to send them the
+                   result. We use a logarithmic recursive-halfing algorithm
+                   for this. */
+
+                if (dst_tree_root + mask > comm_size) {
+                    nprocs_completed = comm_size - my_tree_root - mask;
+                    /* nprocs_completed is the number of processes in this
+                       subtree that have all the data. Send data to others
+                       in a tree fashion. First find root of current tree
+                       that is being divided into two. k is the number of
+                       least-significant bits in this process's rank that
+                       must be zeroed out to find the rank of the root */ 
+                    j = mask;
+                    k = 0;
+                    while (j) {
+                        j >>= 1;
+                        k++;
+                    }
+                    k--;
+
+                    tmp_mask = mask >> 1;
+                    while (tmp_mask) {
+                        dst = rank ^ tmp_mask;
+
+                        tree_root = rank >> k;
+                        tree_root <<= k;
+
+                        /* send only if this proc has data and destination
+                           doesn't have data. at any step, multiple processes
+                           can send if they have the data */
+                        if ((dst > rank) && 
+                            (rank < tree_root + nprocs_completed)
+                            && (dst >= tree_root + nprocs_completed)) {
+                            /* send the current result */
+                            smpi_mpi_send(tmp_recvbuf, 1, recvtype,
+                                                     dst, MPIR_REDUCE_SCATTER_TAG,
+                                                     comm);
+                        }
+                        /* recv only if this proc. doesn't have data and sender
+                           has data */
+                        else if ((dst < rank) && 
+                                 (dst < tree_root + nprocs_completed) &&
+                                 (rank >= tree_root + nprocs_completed)) {
+                            smpi_mpi_recv(tmp_recvbuf, 1, recvtype, dst,
+                                                     MPIR_REDUCE_SCATTER_TAG,
+                                                     comm, MPI_STATUS_IGNORE); 
+                            received = 1;
+                        }
+                        tmp_mask >>= 1;
+                        k--;
+                    }
+                }
+
+                /* The following reduction is done here instead of after 
+                   the MPIC_Sendrecv_ft or MPIC_Recv_ft above. This is
+                   because to do it above, in the noncommutative 
+                   case, we would need an extra temp buffer so as not to
+                   overwrite temp_recvbuf, because temp_recvbuf may have
+                   to be communicated to other processes in the
+                   non-power-of-two case. To avoid that extra allocation,
+                   we do the reduce here. */
+                if (received) {
+                    if (is_commutative || (dst_tree_root < my_tree_root)) {
+                        {
+			         smpi_op_apply(op, 
+                               tmp_recvbuf, tmp_results, &blklens[0],
+			       &datatype); 
+			        smpi_op_apply(op, 
+                               ((char *)tmp_recvbuf + dis[1]*extent),
+			       ((char *)tmp_results + dis[1]*extent),
+			       &blklens[1], &datatype); 
+                        }
+                    }
+                    else {
+                        {
+			         smpi_op_apply(op,
+                                   tmp_results, tmp_recvbuf, &blklens[0],
+                                   &datatype); 
+			         smpi_op_apply(op,
+                                   ((char *)tmp_results + dis[1]*extent),
+                                   ((char *)tmp_recvbuf + dis[1]*extent),
+                                   &blklens[1], &datatype); 
+                        }
+                        /* copy result back into tmp_results */
+                        mpi_errno = smpi_datatype_copy(tmp_recvbuf, 1, recvtype, 
+                                                   tmp_results, 1, recvtype);
+                        if (mpi_errno) return(mpi_errno);
+                    }
+                }
+
+                //smpi_datatype_free(&sendtype);
+                //smpi_datatype_free(&recvtype);
+
+                mask <<= 1;
+                i++;
+            }
+
+            /* now copy final results from tmp_results to recvbuf */
+            mpi_errno = smpi_datatype_copy(((char *)tmp_results+disps[rank]*extent),
+                                       recvcounts[rank], datatype, recvbuf,
+                                       recvcounts[rank], datatype);
+            if (mpi_errno) return(mpi_errno);
+
+    return MPI_SUCCESS;
+        }
+
+