[PATCH 1/2] ring-buffer: replace constants with time macros in ring-buffer-benchmark

From: Steven Rostedt
Date: Fri May 08 2009 - 12:22:01 EST


From: Steven Rostedt <srostedt@xxxxxxxxxx>

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@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
---
kernel/trace/ring_buffer_benchmark.c | 12 +++++++-----
1 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c
index a21aa7b..7d3aef9 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);
}
}
--
1.6.2.4

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