Date: Thu, 27 Nov 2008 12:49:37 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: David Miller <davem@davemloft.net>
cc: eranian@gmail.com, eranian@googlemail.com, andi@firstfloor.org,
       linux-kernel@vger.kernel.org, akpm@linux-foundation.org, mingo@elte.hu,
       x86@kernel.org, sfr@canb.auug.org.au
Subject: Re: [patch 05/24] perfmon: X86 generic code (x86)
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On Thu, 27 Nov 2008, David Miller wrote:

> From: "stephane eranian" <eranian@googlemail.com>
> Date: Thu, 27 Nov 2008 12:35:54 +0100
> 
> > I am still wondering how Oprofile handles the case where multiple
> > processes or threads access the same file descriptor.
> 
> There's only one profiling buffer active on a given cpu,
> so it's pure per-cpu value insertion.
> 
> In any event I think that NMI profiling is a must, especially
> for the kernel.  You get total unusable crap otherwise.  I
> just learned this the hard way having gotten an NMI'ish scheme
> working on sparc64 just the other day.

Not arguing about that, I'm just not agreeing with the implementation.

So for the moment we can go w/o the NMI and implement it cleanly after
we got the initial lot in.

Thanks,

	tglx

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