[svn-r14096] There're 3 changes in this checkin as below:

  1. In H5Dwrite and H5Dread, let the data buffer point to a fake address if the application passes
     in an empty buffer.  This is mainly for MPIO programs that some processes may not have any 
     data to write or read but still participate the I/O.  This solution solves some MPI's problem
     like the ChaMPIon on tungsten which doesn't support empty buffer.
  2. The ChaMPIon on tungsten doesn't support complex derived MPI data type correctly and collective
     I/O when some processes don't have any data to write or read correctly.  Detect the compiler
     "cmpicc" in the system-specific config file and set the variables for these two cases to false.
     The PHDF5 library already has set up a way to switch collective chunked I/O to independent 
     under these two cases.
  3. A bug fix - During the work of the optimization for compound data I/O, the case for switching
     collective chunked I/O to independent I/O was leftout.  Fixed it by adding I/O caching to it in
     H5D_multi_chunk_collective_io in H5Dmpio.c.

Tested on tungsten, cobalt, and kagiso for parallel; on linew and smirom for serial.
  

1 files changed, 212 insertions, 0 deletions

diff --git a/testpar/t_dset.c b/testpar/t_dset.c
index 3c18d82..91349fc 100644
--- a/testpar/t_dset.c
+++ b/testpar/t_dset.c
@@ -2286,3 +2286,215 @@ compress_readAll(void)
 }
 #endif /* H5_HAVE_FILTER_DEFLATE */
 
+/*
+ * Part 4--Non-selection for chunked dataset
+ */
+
+/*
+ * Example of using the parallel HDF5 library to create chunked
+ * dataset in one HDF5 file with collective and independent parallel
+ * MPIO access support.  The Datasets are of sizes dim0 x dim1.
+ * Each process controls only a slab of size dim0 x dim1 within the
+ * dataset with the exception that one processor selects no element.
+ */
+
+void
+none_selection_chunk(void)
+{
+    hid_t fid;                  /* HDF5 file ID */
+    hid_t acc_tpl;		/* File access templates */
+    hid_t xfer_plist;		/* Dataset transfer properties list */
+    hid_t sid;   		/* Dataspace ID */
+    hid_t file_dataspace;	/* File dataspace ID */
+    hid_t mem_dataspace;	/* memory dataspace ID */
+    hid_t dataset1, dataset2;	/* Dataset ID */
+    hbool_t use_gpfs = FALSE;   /* Use GPFS hints */
+    const char *filename;
+    hsize_t dims[RANK];   	/* dataset dim sizes */
+    DATATYPE	*data_origin = NULL;		/* data buffer */
+    DATATYPE	*data_array = NULL;		/* data buffer */
+    hsize_t	chunk_dims[RANK];		/* chunk sizes */
+    hid_t	dataset_pl;			/* dataset create prop. list */
+
+    hsize_t	start[RANK];			/* for hyperslab setting */
+    hsize_t	count[RANK];			/* for hyperslab setting */
+    hsize_t	stride[RANK];			/* for hyperslab setting */
+    hsize_t 	block[RANK];			/* for hyperslab setting */
+    hsize_t	mstart[RANK];			/* for data buffer in memory */
+
+    herr_t ret;         	/* Generic return value */
+    int mpi_size, mpi_rank;
+
+    MPI_Comm comm = MPI_COMM_WORLD;
+    MPI_Info info = MPI_INFO_NULL;
+
+    filename = GetTestParameters();
+    if (VERBOSE_MED)
+	printf("Extend independent write test on file %s\n", filename);
+
+    /* set up MPI parameters */
+    MPI_Comm_size(MPI_COMM_WORLD,&mpi_size);
+    MPI_Comm_rank(MPI_COMM_WORLD,&mpi_rank);
+
+    /* setup chunk-size. Make sure sizes are > 0 */
+    chunk_dims[0] = chunkdim0;
+    chunk_dims[1] = chunkdim1;
+
+    /* -------------------
+     * START AN HDF5 FILE
+     * -------------------*/
+    /* setup file access template */
+    acc_tpl = create_faccess_plist(comm, info, facc_type, use_gpfs);
+    VRFY((acc_tpl >= 0), "");
+
+    /* create the file collectively */
+    fid=H5Fcreate(filename,H5F_ACC_TRUNC,H5P_DEFAULT,acc_tpl);
+    VRFY((fid >= 0), "H5Fcreate succeeded");
+
+    /* Release file-access template */
+    ret=H5Pclose(acc_tpl);
+    VRFY((ret >= 0), "");
+
+    /* --------------------------------------------------------------
+     * Define the dimensions of the overall datasets and create them.
+     * ------------------------------------------------------------- */
+
+    /* set up dataset storage chunk sizes and creation property list */
+    if (VERBOSE_MED)
+	printf("chunks[]=%lu,%lu\n", (unsigned long)chunk_dims[0], (unsigned long)chunk_dims[1]);
+    dataset_pl = H5Pcreate(H5P_DATASET_CREATE);
+    VRFY((dataset_pl >= 0), "H5Pcreate succeeded");
+    ret = H5Pset_chunk(dataset_pl, RANK, chunk_dims);
+    VRFY((ret >= 0), "H5Pset_chunk succeeded");
+
+    /* setup dimensionality object */
+    dims[0] = dim0;
+    dims[1] = dim1;
+    sid = H5Screate_simple (RANK, dims, NULL);
+    VRFY((sid >= 0), "H5Screate_simple succeeded");
+
+    /* create an extendible dataset collectively */
+    dataset1 = H5Dcreate(fid, DATASETNAME1, H5T_NATIVE_INT, sid, dataset_pl);
+    VRFY((dataset1 >= 0), "H5Dcreate succeeded");
+
+    /* create another extendible dataset collectively */
+    dataset2 = H5Dcreate(fid, DATASETNAME2, H5T_NATIVE_INT, sid, dataset_pl);
+    VRFY((dataset2 >= 0), "H5Dcreate succeeded");
+
+    /* release resource */
+    H5Sclose(sid);
+    H5Pclose(dataset_pl);
+
+    /* -------------------------
+     * Test collective writing to dataset1
+     * -------------------------*/
+    /* set up dimensions of the slab this process accesses */
+    slab_set(mpi_rank, mpi_size, start, count, stride, block, BYROW);
+
+    /* allocate memory for data buffer. Only allocate enough buffer for
+     * each processor's data. */
+    if (mpi_rank) {
+        data_origin = (DATATYPE *)malloc(block[0]*block[1]*sizeof(DATATYPE));
+        VRFY((data_origin != NULL), "data_origin malloc succeeded");
+
+        data_array = (DATATYPE *)malloc(block[0]*block[1]*sizeof(DATATYPE));
+        VRFY((data_array != NULL), "data_array malloc succeeded");
+
+        /* put some trivial data in the data_array */
+        mstart[0] = mstart[1] = 0;
+        dataset_fill(mstart, block, data_origin);
+        MESG("data_array initialized");
+        if (VERBOSE_MED){
+	    MESG("data_array created");
+	    dataset_print(mstart, block, data_origin);
+        }
+    }
+
+    /* create a memory dataspace independently */
+    mem_dataspace = H5Screate_simple (RANK, block, NULL);
+    VRFY((mem_dataspace >= 0), "");
+
+    /* Process 0 has no selection */
+    if (!mpi_rank) {
+        ret = H5Sselect_none(mem_dataspace);
+        VRFY((ret >= 0), "H5Sselect_none succeeded");
+    }
+
+    /* create a file dataspace independently */
+    file_dataspace = H5Dget_space (dataset1);
+    VRFY((file_dataspace >= 0), "H5Dget_space succeeded");
+    ret=H5Sselect_hyperslab(file_dataspace, H5S_SELECT_SET, start, stride, count, block);
+    VRFY((ret >= 0), "H5Sset_hyperslab succeeded");
+
+    /* Process 0 has no selection */
+    if (!mpi_rank) {
+        ret = H5Sselect_none(file_dataspace);
+        VRFY((ret >= 0), "H5Sselect_none succeeded");
+    }
+
+    /* set up the collective transfer properties list */
+    xfer_plist = H5Pcreate (H5P_DATASET_XFER);
+    VRFY((xfer_plist >= 0), "H5Pcreate xfer succeeded");
+    ret=H5Pset_dxpl_mpio(xfer_plist, H5FD_MPIO_COLLECTIVE);
+    VRFY((ret >= 0), "H5Pset_dxpl_mpio succeeded");
+
+    /* write data collectively */
+    ret = H5Dwrite(dataset1, H5T_NATIVE_INT, mem_dataspace, file_dataspace,
+	    xfer_plist, data_origin);
+    VRFY((ret >= 0), "H5Dwrite succeeded");
+
+    /* read data independently */
+    ret = H5Dread(dataset1, H5T_NATIVE_INT, mem_dataspace, file_dataspace,
+	    H5P_DEFAULT, data_array);
+    VRFY((ret >= 0), "");
+
+    /* verify the read data with original expected data */
+    if (mpi_rank) {
+        ret = dataset_vrfy(mstart, count, stride, block, data_array, data_origin);
+        if (ret) nerrors++;
+    }
+
+    /* -------------------------
+     * Test independent writing to dataset2
+     * -------------------------*/
+    ret=H5Pset_dxpl_mpio(xfer_plist, H5FD_MPIO_INDEPENDENT);
+    VRFY((ret >= 0), "H5Pset_dxpl_mpio succeeded");
+
+    /* write data collectively */
+    ret = H5Dwrite(dataset2, H5T_NATIVE_INT, mem_dataspace, file_dataspace,
+	    xfer_plist, data_origin);
+    VRFY((ret >= 0), "H5Dwrite succeeded");
+
+    /* read data independently */
+    ret = H5Dread(dataset2, H5T_NATIVE_INT, mem_dataspace, file_dataspace,
+	    H5P_DEFAULT, data_array);
+    VRFY((ret >= 0), "");
+
+    /* verify the read data with original expected data */
+    if (mpi_rank) {
+        ret = dataset_vrfy(mstart, count, stride, block, data_array, data_origin);
+        if (ret) nerrors++;
+    }
+
+    /* release resource */
+    ret=H5Sclose(file_dataspace);
+    VRFY((ret >= 0), "H5Sclose succeeded");
+    ret=H5Sclose(mem_dataspace);
+    VRFY((ret >= 0), "H5Sclose succeeded");
+    ret=H5Pclose(xfer_plist);
+    VRFY((ret >= 0), "H5Pclose succeeded");
+
+
+    /* close dataset collectively */
+    ret=H5Dclose(dataset1);
+    VRFY((ret >= 0), "H5Dclose1 succeeded");
+    ret=H5Dclose(dataset2);
+    VRFY((ret >= 0), "H5Dclose2 succeeded");
+
+    /* close the file collectively */
+    H5Fclose(fid);
+
+    /* release data buffers */
+    if (data_origin) free(data_origin);
+    if (data_array) free(data_array);
+}