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Date: Thu, 2 Apr 2009 20:18:49 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>,
       Corey Ashford <cjashfor@linux.vnet.ibm.com>,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH 5/6] perf_counter: add more context information
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* Peter Zijlstra <a.p.zijlstra@chello.nl> wrote:

> On Thu, 2009-04-02 at 13:36 +0200, Ingo Molnar wrote:
> 
> > > -#define MAX_STACK_DEPTH		255
> > > +#define MAX_STACK_DEPTH		254
> > >  
> > >  struct perf_callchain_entry {
> > > -	u64	nr;
> > > +	u32	nr, hv, kernel, user;
> > >  	u64	ip[MAX_STACK_DEPTH];
> > >  };
> 
> Oh, and Paul suggested using u16s right after I send it out. So 
> I'll either send an update or send a incremental in case you 
> already applied it.

yes, that's probably a good idea. Although u8 might be even better - 
do we ever want to do more than 256 deep stack vectors? Even those 
would take quite some time to construct and pass down.

	Ingo