Re: kernel api for application profiling

[John Levon <levon@movementarian.org>]

On Mon, Oct 14, 2002 at 12:17:23AM +0200, Mikael Pettersson wrote:

> The HW resources in question are the local APIC LVTPC entry
> and the performance counter MSRs. Agreed?

Right.

> The NMI watchdog can either be special-cased so that the resource
> manager knows that it is a low-priority default owner of the HW,
> or we can try to encode this in the interface to the manager, using
> callbacks like "are you willing to release the HW?" and results
> like "yes, but please call this FUNC when you're done with the HW".

I've been thinking along the exact same lines. I even started to
implement something like this originally, but ended up doing a simpler
save/restore thing in oprofile. It would be fairly easy to implement,
the biggest difficulty being the hand-off of the power management
routines and the NMI handler where appropriate.

I agree that it doesn't make sense to split up the resources (though at
some point I'd like to maintain the watchdog functionality even with
oprofile running). In fact, for now, I think the simple exclusive CONFIG
solution is the simplest - the things don't get on together, after all.

regards
john
-- 
"That's just kitten-eating wrong."
	- Richard Henderson