Refine benchmark output.

Change output measurement from time to bandwidth, so we can compare
all benchmark results easily. And change return type of benchmark
from int to double, because int is not precise enough.

v2: Change output measurement from time to bandwidth.

Signed-off-by: Chuanbo Weng <chuanbo.weng@intel.com>
Reviewed-by: Zhigang Gong <zhigang.gong@linux.intel.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/benchmark/benchmark_read_image.cpp b/benchmark/benchmark_read_image.cpp
index 48aa9871..e3aa5bd0 100644
--- a/benchmark/benchmark_read_image.cpp
+++ b/benchmark/benchmark_read_image.cpp
@@ -2,7 +2,7 @@
 #include "utests/utest_helper.hpp"
 #include <sys/time.h>
 
-int benchmark_read_image(void)
+double benchmark_read_image(void)
 {
   struct timeval start,stop;
 
@@ -61,7 +61,9 @@ int benchmark_read_image(void)
   free(buf_data[0]);
   buf_data[0] = NULL;
 
-  return time_subtract(&stop, &start, 0);
+  double elapsed = time_subtract(&stop, &start, 0);
+
+  return BANDWIDTH(sz * sizeof(float) * 2 * 100, elapsed);
 }
 
 MAKE_BENCHMARK_FROM_FUNCTION(benchmark_read_image);