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Date: Tue, 06 Nov 2012 16:12:47 +0530
From: Anshuman Khandual <khandual@linux.vnet.ibm.com>
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To: Michael Neuling <mikey@neuling.org>
Subject: Re: [PATCH 1/2] powerpc/perf: Fix finding overflowed PMC in interrupt
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On 11/06/2012 03:49 PM, Michael Neuling wrote:
>>
>>
>> I have couple of questions. 
>>
>> Can the buggy overflow happen on any of the available counters PMC1-PMC4 ?
> 
> No.  It's limited to certain events and I believe it can only happen on
> PMC2 and 4.  This code doesn't bother trying to make this distinction
> though.
> 
>> Will this approach never reset an actual user defined event (with
>> sample period < 256) ? Is this related to the counter or the event
>> which it is counting ? Just wondering if we have to do something more
>> than checking for the count < 256. Just a thought.
> 
> 
> I don't understand what you mean by these questions.  Can you explain a
> bit more?
> 

Thats fine. The previous answer explains it well. Thanks !