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Subject: Re: [PATCH v2 0/6] Add tracepoints to trace all system IRQs
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Frederic Weisbecker <fweisbec@gmail.com>
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Date: Thu, 28 Jul 2011 15:28:22 +0200
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On Thu, 2011-07-28 at 15:09 +0200, Frederic Weisbecker wrote:
> On Thu, Jul 28, 2011 at 02:53:52PM +0200, Peter Zijlstra wrote:
> > On Thu, 2011-07-28 at 14:31 +0200, Frederic Weisbecker wrote:
> > > 
> > > Because that requires to put the tracepoints in every interrupt sources
> > > for every archs instead of putting one in the generic space. 
> > 
> > Yeah so, he needs to touch arch code anyway.
> 
> He needs to touch arch code for pure arch interrupts or some cases
> where we don't have the choice. But otherwise there are many
> cases where we can put that in the generic code.

Which I just pointed out you can't, some 'generic' handlers are in fact
multiplexed on a single arch interrupt. If you want all interrupts, use
pure arch hooks at the lowest level and stop mucking about.