ring-buffer: replace constants with time macros in ring-buffer-benchmark

The use of numeric constants is discouraged. It is cleaner and more
descriptive to use macros for constant time conversions.

This patch also removes an extra new line.

[ Impact: more descriptive time conversions ]

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 7 insertions, 5 deletions

diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c
index a21aa7b3d05e..7d3aef93c49f 100644
--- a/kernel/trace/ring_buffer_benchmark.c
+++ b/kernel/trace/ring_buffer_benchmark.c
@@ -253,7 +253,7 @@ static void ring_buffer_producer(void)
 	}
 
 	time = end_tv.tv_sec - start_tv.tv_sec;
-	time *= 1000000;
+	time *= USEC_PER_SEC;
 	time += (long long)((long)end_tv.tv_usec - (long)start_tv.tv_usec);
 
 	entries = ring_buffer_entries(buffer);
@@ -273,7 +273,8 @@ static void ring_buffer_producer(void)
 	pr_info("Missed:   %ld\n", missed);
 	pr_info("Hit:      %ld\n", hit);
 
-	do_div(time, 1000);
+	/* Convert time from usecs to millisecs */
+	do_div(time, USEC_PER_MSEC);
 	if (time)
 		hit /= (long)time;
 	else
@@ -282,18 +283,19 @@ static void ring_buffer_producer(void)
 	pr_info("Entries per millisec: %ld\n", hit);
 
 	if (hit) {
-		avg = 1000000 / hit;
+		/* Calculate the average time in nanosecs */
+		avg = NSEC_PER_MSEC / hit;
 		pr_info("%ld ns per entry\n", avg);
 	}
 
-
 	if (missed) {
 		if (time)
 			missed /= (long)time;
 
 		pr_info("Total iterations per millisec: %ld\n", hit + missed);
 
-		avg = 1000000 / (hit + missed);
+		/* Caculate the average time in nanosecs */
+		avg = NSEC_PER_MSEC / (hit + missed);
 		pr_info("%ld ns per entry\n", avg);
 	}
 }