Suggested changes from code review

5 files changed, 60 insertions, 12 deletions

diff --git a/src/H5Dio.c b/src/H5Dio.c
index 8d41960..470520e 100644
--- a/src/H5Dio.c
+++ b/src/H5Dio.c
@@ -1190,7 +1190,7 @@ H5D__ioinfo_adjust(H5D_io_info_t *io_info, const H5D_t *dset, hid_t dxpl_id,
             HGOTO_ERROR(H5E_DATASPACE, H5E_CANTGET, FAIL, "can't retrieve MPI communicator")
 
         /* Check if we can set direct MPI-IO read/write functions */
-        if((opt = H5D__mpio_opt_possible(io_info, file_space, mem_space, type_info, fm, dx_plist)) < 0)
+        if((opt = H5D__mpio_opt_possible(io_info, file_space, mem_space, type_info, dx_plist)) < 0)
             HGOTO_ERROR(H5E_DATASPACE, H5E_BADRANGE, FAIL, "invalid check for direct IO dataspace ")
 
         /* Check if we can use the optimized parallel I/O routines */
@@ -1206,8 +1206,62 @@ H5D__ioinfo_adjust(H5D_io_info_t *io_info, const H5D_t *dset, hid_t dxpl_id,
              * we cannot break to independent I/O if this is a write operation;
              * otherwise there will be metadata inconsistencies in the file.
              */
-            if (io_info->op_type == H5D_IO_OP_WRITE && io_info->dset->shared->dcpl_cache.pline.nused > 0)
-                HGOTO_ERROR(H5E_IO, H5E_NO_INDEPENDENT, FAIL, "can't perform independent write with filters in pipeline")
+            if (io_info->op_type == H5D_IO_OP_WRITE && io_info->dset->shared->dcpl_cache.pline.nused > 0) {
+                H5D_mpio_no_collective_cause_t  cause;
+                uint32_t                        local_no_collective_cause;
+                uint32_t                        global_no_collective_cause;
+                hbool_t                         local_error_message_previously_written = FALSE;
+                hbool_t                         global_error_message_previously_written = FALSE;
+                size_t                          index;
+                char                            local_no_collective_cause_string[256] = "";
+                char                            global_no_collective_cause_string[256] = "";
+                const char                     *cause_strings[] = { "independent I/O was requested",
+                                                                    "datatype conversions were required",
+                                                                    "data transforms needed to be applied",
+                                                                    "optimized MPI types flag wasn't set",
+                                                                    "one of the dataspaces was neither simple nor scalar",
+                                                                    "dataset was not contiguous or chunked" };
+
+                if (H5P_get(dx_plist, H5D_MPIO_LOCAL_NO_COLLECTIVE_CAUSE_NAME, &local_no_collective_cause) < 0)
+                    HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "unable to get local no collective cause value")
+                if (H5P_get(dx_plist, H5D_MPIO_GLOBAL_NO_COLLECTIVE_CAUSE_NAME, &global_no_collective_cause) < 0)
+                    HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "unable to get global no collective cause value")
+
+                /* Append each of the reason for breaking collective I/O error messages to the
+                 * local and global no collective cause strings */
+                for (cause = 1, index = 0; cause < H5D_MPIO_NO_COLLECTIVE_MAX_CAUSE; cause <<= 1, index++) {
+                    size_t cause_strlen = strlen(cause_strings[index]);
+
+                    if (cause & local_no_collective_cause) {
+                        /* Check if there were any previous error messages included. If so, prepend a semicolon
+                         * to separate the messages.
+                         */
+                        if (local_error_message_previously_written) strncat(local_no_collective_cause_string, "; ", 2);
+
+                        strncat(local_no_collective_cause_string, cause_strings[index], cause_strlen);
+
+                        local_error_message_previously_written = TRUE;
+                    } /* end if */
+
+                    if (cause & global_no_collective_cause) {
+                        /* Check if there were any previous error messages included. If so, prepend a semicolon
+                         * to separate the messages.
+                         */
+                        if (global_error_message_previously_written) strncat(global_no_collective_cause_string, "; ", 2);
+
+                        strncat(global_no_collective_cause_string, cause_strings[index], cause_strlen);
+
+                        global_error_message_previously_written = TRUE;
+                    } /* end if */
+                } /* end for */
+
+                HGOTO_ERROR(H5E_IO, H5E_NO_INDEPENDENT, FAIL, "Can't perform independent write with filters in pipeline.\n"
+                                                              "    The following caused a break from collective I/O:\n"
+                                                              "        Local causes: %s\n"
+                                                              "        Global causes: %s",
+                                                              local_no_collective_cause_string,
+                                                              global_no_collective_cause_string);
+            } /* end if */
 
             /* If we won't be doing collective I/O, but the user asked for
              * collective I/O, change the request to use independent I/O, but
diff --git a/src/H5Dmpio.c b/src/H5Dmpio.c
index e70f51e..393e155 100644
--- a/src/H5Dmpio.c
+++ b/src/H5Dmpio.c
@@ -202,8 +202,7 @@ static int H5D__cmp_filtered_collective_io_info_entry_owner(const void *filtered
  */
 htri_t
 H5D__mpio_opt_possible(const H5D_io_info_t *io_info, const H5S_t *file_space,
-    const H5S_t *mem_space, const H5D_type_info_t *type_info,
-    const H5D_chunk_map_t H5_ATTR_UNUSED *fm, H5P_genplist_t *dx_plist)
+    const H5S_t *mem_space, const H5D_type_info_t *type_info, H5P_genplist_t *dx_plist)
 {
     int local_cause = 0;        /* Local reason(s) for breaking collective mode */
     int global_cause = 0;       /* Global reason(s) for breaking collective mode */
diff --git a/src/H5Dpkg.h b/src/H5Dpkg.h
index 5e3a70d..097fab7 100644
--- a/src/H5Dpkg.h
+++ b/src/H5Dpkg.h
@@ -773,8 +773,7 @@ H5_DLL herr_t H5D__chunk_collective_write(H5D_io_info_t *io_info,
  * memory and the file */
 H5_DLL htri_t H5D__mpio_opt_possible(const H5D_io_info_t *io_info,
     const H5S_t *file_space, const H5S_t *mem_space,
-    const H5D_type_info_t *type_info, const H5D_chunk_map_t *fm,
-    H5P_genplist_t *dx_plist);
+    const H5D_type_info_t *type_info, H5P_genplist_t *dx_plist);
 
 #endif /* H5_HAVE_PARALLEL */
 
diff --git a/src/H5Ppublic.h b/src/H5Ppublic.h
index 55b3877..854b1ef 100644
--- a/src/H5Ppublic.h
+++ b/src/H5Ppublic.h
@@ -166,7 +166,7 @@ typedef enum H5D_mpio_no_collective_cause_t {
     H5D_MPIO_MPI_OPT_TYPES_ENV_VAR_DISABLED = 0x08,
     H5D_MPIO_NOT_SIMPLE_OR_SCALAR_DATASPACES = 0x10,
     H5D_MPIO_NOT_CONTIGUOUS_OR_CHUNKED_DATASET = 0x20,
-    H5D_MPIO_FILTERS = 0x40
+    H5D_MPIO_NO_COLLECTIVE_MAX_CAUSE = 0x40
 } H5D_mpio_no_collective_cause_t;
 
 /********************/
diff --git a/src/H5trace.c b/src/H5trace.c
index 9fb8a72..930002f 100644
--- a/src/H5trace.c
+++ b/src/H5trace.c
@@ -621,10 +621,6 @@ H5_trace(const double *returning, const char *func, const char *type, ...)
                                 fprintf(out, "%sH5D_MPIO_NOT_CONTIGUOUS_OR_CHUNKED_DATASET", flag_already_displayed ? " | " : "");
                                 flag_already_displayed = TRUE;
                             } /* end if */
-                            if(nocol_cause_mode & H5D_MPIO_FILTERS) {
-                                fprintf(out, "%sH5D_MPIO_FILTERS", flag_already_displayed ? " | " : "");
-                                flag_already_displayed = TRUE;
-                            } /* end if */
 
                             /* Display '<none>' if there's no flags set */
                             if(!flag_already_displayed)