public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Steven Rostedt <rostedt@goodmis.org>
To: linux-kernel@vger.kernel.org
Cc: Ingo Molnar <mingo@elte.hu>, Andrew Morton <akpm@linux-foundation.org>
Subject: [PATCH 1/2] ring-buffer: replace constants with time macros in ring-buffer-benchmark
Date: Fri, 08 May 2009 12:20:34 -0400	[thread overview]
Message-ID: <20090508162131.981675126@goodmis.org> (raw)
In-Reply-To: 20090508162033.397923239@goodmis.org

[-- Attachment #1: 0001-ring-buffer-replace-constants-with-time-macros-in-r.patch --]
[-- Type: text/plain, Size: 1805 bytes --]

From: Steven Rostedt <srostedt@redhat.com>

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>
---
 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

-- 

  reply	other threads:[~2009-05-08 16:21 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-05-08 16:20 [PATCH 0/2] [GIT PULL] ring-buffer: fixes suggested by Andrew Steven Rostedt
2009-05-08 16:20 ` Steven Rostedt [this message]
2009-05-08 16:20 ` [PATCH 2/2] ring-buffer: check for divide by zero in ring-buffer-benchmark Steven Rostedt

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20090508162131.981675126@goodmis.org \
    --to=rostedt@goodmis.org \
    --cc=akpm@linux-foundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox