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Date: Thu, 7 May 2009 21:52:58 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>
Subject: Re: [PATCH 3/4] ring-buffer: add total count in
 ring-buffer-benchmark
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On Fri, 08 May 2009 00:32:53 -0400 Steven Rostedt <rostedt@goodmis.org> wrote:

> --- a/kernel/trace/ring_buffer_benchmark.c
> +++ b/kernel/trace/ring_buffer_benchmark.c
> @@ -285,6 +285,17 @@ static void ring_buffer_producer(void)
>  		avg = 1000000 / hit;
>  		pr_info("%ld ns per entry\n", avg);
>  	}
> +
> +

s/\n\n/\n/

> +	if (missed) {
> +		if (time)
> +			missed /= (long)time;
> +
> +		pr_info("Total iterations per millisec: %ld\n", hit + missed);
> +
> +		avg = 1000000 / (hit + missed);

s/1000000/USEC_PER_SEC/?

Hopefully we can't have hit+missed==0.

They're counters and hence should have unsigned types.

But even unsigned up-counters can add to zero if wrapping occurs.


> +		pr_info("%ld ns per entry\n", avg);
> +	}
>  }