common/ompio: fix a floating point division problem

This commit fixes  a problem reported on the mailing list with
individual writes larger than 512 MB.

The culprit is a floating point division of two large, close values.
Changing the datatypes from float to double (which is what is being
used in the fcoll components) fixes the problem.

See issue #6285 and

 https://forum.hdfgroup.org/t/cannot-write-more-than-512-mb-in-1d/5118

Thanks for Axel Huebl and René Widera for reporting the issue.

Signed-off-by: Edgar Gabriel <[email protected]>
(cherry picked from commit c0f8ce0)

Author: edgargabriel

ompi/mca/common/ompio/common_ompio_file_read.c

@@ -9,7 +9,9 @@
  *                          University of Stuttgart.  All rights reserved.
  *  Copyright (c) 2004-2005 The Regents of the University of California.
  *                          All rights reserved.
- *  Copyright (c) 2008-2016 University of Houston. All rights reserved.
+ *  Copyright (c) 2008-2019 University of Houston. All rights reserved.
+ *  Copyright (c) 2018      Research Organization for Information Science
+ *                          and Technology (RIST). All rights reserved.
  *  $COPYRIGHT$
  *
  *  Additional copyrights may follow
@@ -34,6 +36,7 @@
 #include "ompi/mca/io/ompio/io_ompio_request.h"
 #include "math.h"
 #include <unistd.h>
+#include <math.h>
 
 /* Read and write routines are split into two interfaces.
 **   The
@@ -99,8 +102,8 @@ int mca_common_ompio_file_read (mca_io_ompio_file_t *fh,
     else {
 	bytes_per_cycle = mca_io_ompio_cycle_buffer_size;
     }
-    cycles = ceil((float)max_data/bytes_per_cycle);
-
+    cycles = ceil((double)max_data/bytes_per_cycle);
+    
 #if 0
 	printf ("Bytes per Cycle: %d   Cycles: %d max_data:%d \n",bytes_per_cycle, cycles, max_data);
 #endif

ompi/mca/common/ompio/common_ompio_file_write.c

@@ -9,8 +9,8 @@
  *                         University of Stuttgart.  All rights reserved.
  * Copyright (c) 2004-2005 The Regents of the University of California.
  *                         All rights reserved.
- * Copyright (c) 2008-2016 University of Houston. All rights reserved.
- * Copyright (c) 2015-2017 Research Organization for Information Science
+ * Copyright (c) 2008-2019 University of Houston. All rights reserved.
+ * Copyright (c) 2015-2018 Research Organization for Information Science
  *                         and Technology (RIST). All rights reserved.
  * $COPYRIGHT$
  *
@@ -34,6 +34,7 @@
 #include "ompi/mca/io/ompio/io_ompio_request.h"
 #include "math.h"
 #include <unistd.h>
+#include <math.h>
 
 int mca_common_ompio_file_write (mca_io_ompio_file_t *fh,
 			       const void *buf,
@@ -76,7 +77,7 @@ int mca_common_ompio_file_write (mca_io_ompio_file_t *fh,
     else {
 	bytes_per_cycle = mca_io_ompio_cycle_buffer_size;
     }
-    cycles = ceil((float)max_data/bytes_per_cycle);
+    cycles = ceil((double)max_data/bytes_per_cycle);
 
 #if 0
     printf ("Bytes per Cycle: %d   Cycles: %d\n", bytes_per_cycle, cycles);