common/ompio: incorporate George's comments

incorporate a couple of comments by George as part of the
review on github.

Signed-off-by: Edgar Gabriel <egabriel@central.uh.edu>

ompi/mca/common/ompio/common_ompio_cuda.c

@@ -22,6 +22,7 @@
 #include "opal/datatype/opal_convertor.h"
 #include "opal/datatype/opal_datatype_cuda.h"
 #include "opal/mca/common/cuda/common_cuda.h"
+#include "opal/util/sys_limits.h"
 
 #include "opal/mca/allocator/allocator.h"
 #include "opal/mca/allocator/base/base.h"
@@ -60,13 +61,9 @@ void mca_common_ompio_check_gpu_buf ( ompio_file_t *fh, const void *buf, int *is
 static void* mca_common_ompio_cuda_alloc_seg ( void*ctx, size_t *size )
 {
     char *buf=NULL;
-    size_t realsize, numpages, rest;
+    size_t realsize, numpages;
 
-    numpages = *size / mca_common_ompio_pagesize;
-    rest = *size % mca_common_ompio_pagesize;
-    if ( rest ) {
-        numpages++;
-    }
+    numpages = (*size + mca_common_ompio_pagesize -1 )/mca_common_ompio_pagesize;
     realsize = numpages * mca_common_ompio_pagesize;
 
     buf = malloc ( realsize);
@@ -81,8 +78,8 @@ static void mca_common_ompio_cuda_free_seg ( void *ctx, void *buf )
 {
     if ( NULL != buf ) {
         mca_common_cuda_unregister ( (char *) buf, NULL );
+        free ( buf );
     }
-    free ( buf );
     return;
 }
 
@@ -113,7 +110,8 @@ int mca_common_ompio_cuda_alloc_init ( void )
         return OMPI_ERR_BUFFER;
     }
 
-    mca_common_ompio_pagesize = sysconf(_SC_PAGESIZE);
+//    mca_common_ompio_pagesize = sysconf(_SC_PAGESIZE);
+    mca_common_ompio_pagesize = opal_getpagesize();
 
     OPAL_THREAD_UNLOCK(&mca_common_ompio_cuda_mutex);
     return OMPI_SUCCESS;

ompi/mca/common/ompio/common_ompio_cuda.h

@@ -27,6 +27,10 @@
     opal_convertor_prepare_for_send ( _convertor, &(_datatype->super), _count, _buf );\
     opal_convertor_get_packed_size( _convertor, &_max_data );           \
     _tbuf = mca_common_ompio_alloc_buf (_fh, _max_data);                \
+    if ( NULL == _tbuf ) {                                              \
+        opal_output(1, "common_ompio: error allocating memory\n");      \
+        return OMPI_ERR_OUT_OF_RESOURCE;                                \
+    }                                                                   \
     _decoded_iov = (struct iovec *) malloc ( sizeof ( struct iovec ));  \
     if ( NULL == _decoded_iov ) {                                       \
         opal_output(1, "common_ompio: could not allocate memory.\n");   \

ompi/mca/common/ompio/common_ompio_file_read.c

@@ -91,7 +91,7 @@ int mca_common_ompio_file_read (ompio_file_t *fh,
     }
 
 #if OPAL_CUDA_SUPPORT
-    int is_gpu=0, is_managed=0;
+    int is_gpu, is_managed;
     opal_convertor_t convertor;
     mca_common_ompio_check_gpu_buf ( fh, buf, &is_gpu, &is_managed);
     if ( is_gpu && !is_managed ) {
@@ -243,7 +243,7 @@ int mca_common_ompio_file_iread (ompio_file_t *fh,
         int j = 0; /* index into the file vie iovec */
         
 #if OPAL_CUDA_SUPPORT
-        int is_gpu=0, is_managed=0;
+        int is_gpu, is_managed;
         mca_common_ompio_check_gpu_buf ( fh, buf, &is_gpu, &is_managed);
         if ( is_gpu && !is_managed ) {
             char *tbuf=NULL;

ompi/mca/common/ompio/common_ompio_file_write.c

@@ -66,7 +66,7 @@ int mca_common_ompio_file_write (ompio_file_t *fh,
     }
 
 #if OPAL_CUDA_SUPPORT
-    int is_gpu=0, is_managed=0;
+    int is_gpu, is_managed;
     mca_common_ompio_check_gpu_buf ( fh, buf, &is_gpu, &is_managed);
     if ( is_gpu && !is_managed ) {
         size_t pos=0;
@@ -209,7 +209,7 @@ int mca_common_ompio_file_iwrite (ompio_file_t *fh,
         int j = 0; /* index into the file vie iovec */
 
 #if OPAL_CUDA_SUPPORT
-        int is_gpu=0, is_managed=0;
+        int is_gpu, is_managed;
         mca_common_ompio_check_gpu_buf ( fh, buf, &is_gpu, &is_managed);
         if ( is_gpu && !is_managed ) {
             size_t pos=0;