Re: [RFC 1/3] Unified NMI delayed call mechanism

[Ingo Molnar <mingo@elte.hu>]

* Andi Kleen <andi@firstfloor.org> wrote:

> > I think the perf event subsytem can log events in NMI context already and 
> > deliver them to userspace when the NMI is done.  This is why I think Ingo 
> > wants MCE to be updated to sit on top of the perf event subsytem to avoid 
> > re-invent everything again.
> 
> perf is not solving the problem this is trying to solve.

That is why i requested to extend the events backend. That will unify more of 
the code than the first few steps achieved by these three patches - and offers 
the functionality to all code that uses the events framework.

> [...]
>
> perf does not fit into this because it has no way to process such an event 
> inside the kernel.

It 'does not fit' into the events backend only if you pretend that it is 
impossible or undesirable to have a delayed, in-context callback mechanism 
implemented there.

If you look at it more closely you'll notice that in reality it's not only 
possible but that it is also a pretty natural fit.

Thanks,

	Ingo