From mboxrd@z Thu Jan  1 00:00:00 1970
From: will.deacon@arm.com (Will Deacon)
Date: Mon, 30 Jan 2012 17:24:38 +0000
Subject: oprofile and ARM A9 hardware counter
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To: linux-arm-kernel@lists.infradead.org
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On Mon, Jan 30, 2012 at 05:15:53PM +0000, stephane eranian wrote:
> Still need to investigate why the frequency mode does
> not yield the correct number of samples even with low frequency.
> 
> 
> $ taskset -c 1 perf record -e cycles -F 100 noploop 10
> $ perf report -D | tail -20
> Aggregated stats:
>            TOTAL events:        475
>             MMAP events:         11
>             COMM events:          2
>             EXIT events:          2
>           SAMPLE events:        460
> cycles stats:
>            TOTAL events:        475
>             MMAP events:         11
>             COMM events:          2
>             EXIT events:          2
>           SAMPLE events:        460
> 
> 460 samples is way too low. Should be 100x10 = 1000 samples or close to it.

Can you stick noploop.c somewhere (I'm lazy :) and I'll try it on one of my
A9 boards?

Thanks,

Will