Merge pull request #1127 in HDFFV/hdf5 from ~JHENDERSON/hdf5:develop to develop

* commit 'a8d6f100cdddbfc42d0c4abfeb4ceb8788b1b087':
  Add note about single chunk caching and serial library
  Add check for actually using the MPI file driver when caching one chunk
  Fix error message mentioning wrong MPI function used
  Fix for HDFFV-10509
  Revise H5D__mpio_array_gatherv() to not allocate memory needlessly
  Add test to continually grow and shrink chunks
  Changes to test with checksum filter as well as deflate filter
  Eliminate warning about signed to unsigned conversion
  Remove unused local variable
  Fix bug in parallel reads of compressed data
  Add data verification to parallel filtered compound write tests
  Add seven of fourteen parallel filtered data partial read tests

1 files changed, 98 insertions, 51 deletions

diff --git a/src/H5Dmpio.c b/src/H5Dmpio.c
index bc37840..d721ae6 100644
--- a/src/H5Dmpio.c
+++ b/src/H5Dmpio.c
@@ -234,7 +234,7 @@ static herr_t H5D__chunk_redistribute_shared_chunks(const H5D_io_info_t *io_info
     H5D_filtered_collective_io_info_t *local_chunk_array, size_t *local_chunk_array_num_entries);
 static herr_t H5D__mpio_array_gatherv(void *local_array, size_t local_array_num_entries,
     size_t array_entry_size, void **gathered_array, size_t *gathered_array_num_entries,
-    int nprocs, hbool_t allgather, int root, MPI_Comm comm, int (*sort_func)(const void *, const void *));
+    hbool_t allgather, int root, MPI_Comm comm, int (*sort_func)(const void *, const void *));
 static herr_t H5D__mpio_filtered_collective_write_type(
     H5D_filtered_collective_io_info_t *chunk_list, size_t num_entries,
     MPI_Datatype *new_mem_type, hbool_t *mem_type_derived,
@@ -418,19 +418,16 @@ done:
  * Function:    H5D__mpio_array_gatherv
  *
  * Purpose:     Given an array, specified in local_array, by each processor
- *              calling this function, gathers each array into a single
+ *              calling this function, collects each array into a single
  *              array which is then either gathered to the processor
  *              specified by root, when allgather is false, or is
  *              distributed back to all processors when allgather is true.
  *
- *              The size of each entry and number of entries in the array
- *              contributed by an individual processor should be specified
- *              in array_entry_size and local_array_num_entries,
+ *              The number of entries in the array contributed by an
+ *              individual processor and the size of each entry should be
+ *              specified in local_array_num_entries and array_entry_size,
  *              respectively.
  *
- *              The number of processors participating in the gather
- *              operation should be specified for nprocs.
- *
  *              The MPI communicator to use should be specified for comm.
  *
  *              If the sort_func argument is supplied, the array is sorted
@@ -448,14 +445,13 @@ done:
 static herr_t
 H5D__mpio_array_gatherv(void *local_array, size_t local_array_num_entries,
     size_t array_entry_size, void **_gathered_array, size_t *_gathered_array_num_entries,
-    int nprocs, hbool_t allgather, int root, MPI_Comm comm, int (*sort_func)(const void *, const void *))
+    hbool_t allgather, int root, MPI_Comm comm, int (*sort_func)(const void *, const void *))
 {
     size_t  gathered_array_num_entries = 0; /* The size of the newly-constructed array */
-    size_t  i;
     void   *gathered_array = NULL;          /* The newly-constructed array returned to the caller */
-    int    *receive_counts_array = NULL;    /* Array containing number of entries each process is contributing */
-    int    *displacements_array = NULL;     /* Array of displacements where each process places its data in the final array */
-    int     mpi_code;
+    int    *receive_counts_array = NULL;    /* Array containing number of entries each processor is contributing */
+    int    *displacements_array = NULL;     /* Array of displacements where each processor places its data in the final array */
+    int     mpi_code, mpi_rank, mpi_size;
     int     sendcount;
     herr_t  ret_value = SUCCEED;
 
@@ -464,34 +460,62 @@ H5D__mpio_array_gatherv(void *local_array, size_t local_array_num_entries,
     HDassert(_gathered_array);
     HDassert(_gathered_array_num_entries);
 
-    /* Determine the size of the end result array */
+    MPI_Comm_size(comm, &mpi_size);
+    MPI_Comm_rank(comm, &mpi_rank);
+
+    /*
+     * Determine the size of the end result array by collecting the number
+     * of entries contributed by each processor into a single total.
+     */
     if (MPI_SUCCESS != (mpi_code = MPI_Allreduce(&local_array_num_entries, &gathered_array_num_entries, 1, MPI_INT, MPI_SUM, comm)))
         HMPI_GOTO_ERROR(FAIL, "MPI_Allreduce failed", mpi_code)
 
-    /* If 0 entries resulted from the collective operation, no one is writing anything */
+    /* If 0 entries resulted from the collective operation, no processor is contributing anything and there is nothing to do */
     if (gathered_array_num_entries > 0) {
-        if (NULL == (gathered_array = H5MM_malloc(gathered_array_num_entries * array_entry_size)))
-            HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "couldn't allocate gathered array")
+        /*
+         * If gathering to all processors, all processors need to allocate space for the resulting array, as well as
+         * the receive counts and displacements arrays for the collective MPI_Allgatherv call. Otherwise, only the
+         * root processor needs to allocate the space for an MPI_Gatherv call.
+         */
+        if (allgather || (mpi_rank == root)) {
+            if (NULL == (gathered_array = H5MM_malloc(gathered_array_num_entries * array_entry_size)))
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "couldn't allocate gathered array")
 
-        if (NULL == (receive_counts_array = (int *) H5MM_malloc((size_t) nprocs * sizeof(int))))
-            HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "couldn't allocate receive counts array")
+            if (NULL == (receive_counts_array = (int *) H5MM_malloc((size_t) mpi_size * sizeof(int))))
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "couldn't allocate receive counts array")
 
-        if (NULL == (displacements_array = (int *) H5MM_malloc((size_t) nprocs * sizeof(int))))
-            HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "couldn't allocate receive displacements array")
+            if (NULL == (displacements_array = (int *) H5MM_malloc((size_t) mpi_size * sizeof(int))))
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "couldn't allocate receive displacements array")
+        } /* end if */
 
-        /* Inform each process of how many entries each other process is contributing to the resulting array */
-        if (MPI_SUCCESS != (mpi_code = MPI_Allgather(&local_array_num_entries, 1, MPI_INT, receive_counts_array, 1, MPI_INT, comm)))
-            HMPI_GOTO_ERROR(FAIL, "MPI_Allgather failed", mpi_code)
+        /*
+         * If gathering to all processors, inform each processor of how many entries each other processor is
+         * contributing to the resulting array by collecting the counts into each processor's "receive counts"
+         * array. Otherwise, inform only the root processor of how many entries each other processor is contributing.
+         */
+        if (allgather) {
+            if (MPI_SUCCESS != (mpi_code = MPI_Allgather(&local_array_num_entries, 1, MPI_INT, receive_counts_array, 1, MPI_INT, comm)))
+                HMPI_GOTO_ERROR(FAIL, "MPI_Allgather failed", mpi_code)
+        } /* end if */
+        else {
+            if (MPI_SUCCESS != (mpi_code = MPI_Gather(&local_array_num_entries, 1, MPI_INT, receive_counts_array, 1, MPI_INT, root, comm)))
+                HMPI_GOTO_ERROR(FAIL, "MPI_Gather failed", mpi_code)
+        } /* end else */
 
-        /* Multiply each receive count by the size of the array entry, since the data is sent as bytes */
-        for (i = 0; i < (size_t) nprocs; i++)
-            H5_CHECKED_ASSIGN(receive_counts_array[i], int, (size_t) receive_counts_array[i] * array_entry_size, size_t);
+        if (allgather || (mpi_rank == root)) {
+            size_t i;
 
-        /* Set receive buffer offsets for MPI_Allgatherv */
-        displacements_array[0] = 0;
-        for (i = 1; i < (size_t) nprocs; i++)
-            displacements_array[i] = displacements_array[i - 1] + receive_counts_array[i - 1];
+            /* Multiply each receive count by the size of the array entry, since the data is sent as bytes. */
+            for (i = 0; i < (size_t) mpi_size; i++)
+                H5_CHECKED_ASSIGN(receive_counts_array[i], int, (size_t) receive_counts_array[i] * array_entry_size, size_t);
 
+            /* Set receive buffer offsets for the collective MPI_Allgatherv/MPI_Gatherv call. */
+            displacements_array[0] = 0;
+            for (i = 1; i < (size_t) mpi_size; i++)
+                displacements_array[i] = displacements_array[i - 1] + receive_counts_array[i - 1];
+        } /* end if */
+
+        /* As the data is sent as bytes, calculate the true sendcount for the data. */
         H5_CHECKED_ASSIGN(sendcount, int, local_array_num_entries * array_entry_size, size_t);
 
         if (allgather) {
@@ -502,10 +526,11 @@ H5D__mpio_array_gatherv(void *local_array, size_t local_array_num_entries,
         else {
             if (MPI_SUCCESS != (mpi_code = MPI_Gatherv(local_array, sendcount, MPI_BYTE,
                     gathered_array, receive_counts_array, displacements_array, MPI_BYTE, root, comm)))
-                HMPI_GOTO_ERROR(FAIL, "MPI_Allgatherv failed", mpi_code)
+                HMPI_GOTO_ERROR(FAIL, "MPI_Gatherv failed", mpi_code)
         } /* end else */
 
-        if (sort_func) HDqsort(gathered_array, gathered_array_num_entries, array_entry_size, sort_func);
+        if (sort_func && (allgather || (mpi_rank == root)))
+            HDqsort(gathered_array, gathered_array_num_entries, array_entry_size, sort_func);
     } /* end if */
 
     *_gathered_array = gathered_array;
@@ -1295,8 +1320,7 @@ H5D__link_chunk_filtered_collective_io(H5D_io_info_t *io_info, const H5D_type_in
          * of the chunks in the file.
          */
         if (H5D__mpio_array_gatherv(chunk_list, chunk_list_num_entries, sizeof(H5D_filtered_collective_io_info_t),
-                (void **) &collective_chunk_list, &collective_chunk_list_num_entries, mpi_size,
-                true, 0, io_info->comm, NULL) < 0)
+                (void **) &collective_chunk_list, &collective_chunk_list_num_entries, true, 0, io_info->comm, NULL) < 0)
             HGOTO_ERROR(H5E_DATASET, H5E_CANTGATHER, FAIL, "couldn't gather new chunk sizes")
 
         /* Collectively re-allocate the modified chunks (from each process) in the file */
@@ -1768,8 +1792,7 @@ H5D__multi_chunk_filtered_collective_io(H5D_io_info_t *io_info, const H5D_type_i
              * of the chunks in the file
              */
             if (H5D__mpio_array_gatherv(&chunk_list[i], have_chunk_to_process ? 1 : 0, sizeof(H5D_filtered_collective_io_info_t),
-                    (void **) &collective_chunk_list, &collective_chunk_list_num_entries, mpi_size,
-                    true, 0, io_info->comm, NULL) < 0)
+                    (void **) &collective_chunk_list, &collective_chunk_list_num_entries, true, 0, io_info->comm, NULL) < 0)
                 HGOTO_ERROR(H5E_DATASET, H5E_CANTGATHER, FAIL, "couldn't gather new chunk sizes")
 
             /* Participate in the collective re-allocation of all chunks modified
@@ -2655,8 +2678,8 @@ H5D__chunk_redistribute_shared_chunks(const H5D_io_info_t *io_info, const H5D_ty
      * call, the gathered list will initially be sorted in increasing order of chunk offset in the file.
      */
     if (H5D__mpio_array_gatherv(local_chunk_array, *local_chunk_array_num_entries, sizeof(H5D_filtered_collective_io_info_t),
-            (void **) &shared_chunks_info_array, &shared_chunks_info_array_num_entries, mpi_size,
-            false, 0, io_info->comm, H5D__cmp_filtered_collective_io_info_entry) < 0)
+            (void **) &shared_chunks_info_array, &shared_chunks_info_array_num_entries, false, 0,
+            io_info->comm, H5D__cmp_filtered_collective_io_info_entry) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTGATHER, FAIL, "couldn't gather array")
 
     /* Rank 0 redistributes any shared chunks to new owners as necessary */
@@ -2981,7 +3004,7 @@ H5D__filtered_collective_chunk_entry_io(H5D_filtered_collective_io_info_t *chunk
 {
     H5D_chunk_info_t *chunk_info = NULL;
     H5S_sel_iter_t   *mem_iter = NULL; /* Memory iterator for H5D__scatter_mem/H5D__gather_mem */
-    unsigned char    *mod_data = NULL; /* Chunk modification data sent by a process to a chunk's owner */
+    H5S_sel_iter_t   *file_iter = NULL;
     H5Z_EDC_t         err_detect;       /* Error detection info */
     H5Z_cb_t          filter_cb;        /* I/O filter callback function */
     unsigned          filter_mask = 0;
@@ -2989,11 +3012,13 @@ H5D__filtered_collective_chunk_entry_io(H5D_filtered_collective_io_info_t *chunk
     hssize_t          extent_npoints;
     hsize_t           true_chunk_size;
     hbool_t           mem_iter_init = FALSE;
+    hbool_t           file_iter_init = FALSE;
     size_t            buf_size;
     size_t            i;
     H5S_t            *dataspace = NULL; /* Other process' dataspace for the chunk */
-    void             *tmp_gath_buf = NULL; /* Temporary gather buffer for owner of the chunk to gather into from
-                                            application write buffer before scattering out to the chunk data buffer */
+    void             *tmp_gath_buf = NULL; /* Temporary gather buffer to gather into from application buffer
+                                              before scattering out to the chunk data buffer (when writing data),
+                                              or vice versa (when reading data) */
     int               mpi_code;
     herr_t            ret_value = SUCCEED;
 
@@ -3073,9 +3098,6 @@ H5D__filtered_collective_chunk_entry_io(H5D_filtered_collective_io_info_t *chunk
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize memory selection information")
     mem_iter_init = TRUE;
 
-    if ((iter_nelmts = H5S_GET_SELECT_NPOINTS(chunk_info->mspace)) < 0)
-        HGOTO_ERROR(H5E_DATASET, H5E_CANTCOUNT, FAIL, "dataspace is invalid")
-
     /* If this is a read operation, scatter the read chunk data to the user's buffer.
      *
      * If this is a write operation, update the chunk data buffer with the modifications
@@ -3084,16 +3106,39 @@ H5D__filtered_collective_chunk_entry_io(H5D_filtered_collective_io_info_t *chunk
      */
     switch (io_info->op_type) {
         case H5D_IO_OP_READ:
-            if (H5D__scatter_mem(chunk_entry->buf, chunk_info->mspace, mem_iter, (size_t)iter_nelmts, io_info->u.rbuf) < 0)
-                HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "couldn't scatter to read buffer")
+            if (NULL == (file_iter = (H5S_sel_iter_t *) H5MM_malloc(sizeof(H5S_sel_iter_t))))
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "couldn't allocate file iterator")
+
+            if (H5S_select_iter_init(file_iter, chunk_info->fspace, type_info->src_type_size) < 0)
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize memory selection information")
+            file_iter_init = TRUE;
+
+            if ((iter_nelmts = H5S_GET_SELECT_NPOINTS(chunk_info->fspace)) < 0)
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTCOUNT, FAIL, "dataspace is invalid")
+
+            if (NULL == (tmp_gath_buf = H5MM_malloc((hsize_t) iter_nelmts * type_info->src_type_size)))
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "couldn't allocate temporary gather buffer")
+
+            if (!H5D__gather_mem(chunk_entry->buf, chunk_info->fspace, file_iter, (size_t) iter_nelmts, tmp_gath_buf))
+                HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL, "couldn't gather from chunk buffer")
+
+            if ((iter_nelmts = H5S_GET_SELECT_NPOINTS(chunk_info->mspace)) < 0)
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTCOUNT, FAIL, "dataspace is invalid")
+
+            if (H5D__scatter_mem(tmp_gath_buf, chunk_info->mspace, mem_iter, (size_t) iter_nelmts, io_info->u.rbuf) < 0)
+                   HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "couldn't scatter to read buffer")
+
             break;
 
         case H5D_IO_OP_WRITE:
+            if ((iter_nelmts = H5S_GET_SELECT_NPOINTS(chunk_info->mspace)) < 0)
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTCOUNT, FAIL, "dataspace is invalid")
+
             if (NULL == (tmp_gath_buf = H5MM_malloc((hsize_t) iter_nelmts * type_info->src_type_size)))
                 HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "couldn't allocate temporary gather buffer")
 
             /* Gather modification data from the application write buffer into a temporary buffer */
-            if(!H5D__gather_mem(io_info->u.wbuf, chunk_info->mspace, mem_iter, (size_t)iter_nelmts, tmp_gath_buf))
+            if(!H5D__gather_mem(io_info->u.wbuf, chunk_info->mspace, mem_iter, (size_t) iter_nelmts, tmp_gath_buf))
                 HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "couldn't gather from write buffer")
 
             if (H5S_SELECT_ITER_RELEASE(mem_iter) < 0)
@@ -3111,7 +3156,7 @@ H5D__filtered_collective_chunk_entry_io(H5D_filtered_collective_io_info_t *chunk
             /* Scatter the owner's modification data into the chunk data buffer according to
              * the file space.
              */
-            if(H5D__scatter_mem(tmp_gath_buf, chunk_info->fspace, mem_iter, (size_t)iter_nelmts, chunk_entry->buf) < 0)
+            if(H5D__scatter_mem(tmp_gath_buf, chunk_info->fspace, mem_iter, (size_t) iter_nelmts, chunk_entry->buf) < 0)
                 HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "couldn't scatter to chunk data buffer")
 
             if (H5S_SELECT_ITER_RELEASE(mem_iter) < 0)
@@ -3177,10 +3222,12 @@ done:
         H5MM_free(chunk_entry->async_info.receive_buffer_array);
     if (chunk_entry->async_info.receive_requests_array)
         H5MM_free(chunk_entry->async_info.receive_requests_array);
-    if (mod_data)
-        H5MM_free(mod_data);
     if (tmp_gath_buf)
         H5MM_free(tmp_gath_buf);
+    if (file_iter_init && H5S_SELECT_ITER_RELEASE(file_iter) < 0)
+        HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "couldn't release selection iterator")
+    if (file_iter)
+        H5MM_free(file_iter);
     if (mem_iter_init && H5S_SELECT_ITER_RELEASE(mem_iter) < 0)
         HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "couldn't release selection iterator")
     if (mem_iter)