[PATCH 4/6] perf-events: export enable/disable event symbols to kernel modules

[Peter Zijlstra]

On Wed, 2010-03-10 at 11:47 +0000, Will Deacon wrote:
> Hello Peter,
> 
> > On Wed, 2010-03-10 at 10:41 +0000, Will Deacon wrote:
> > > The perf_event_enable and perf_event_disable functions are used to
> > > control the activation of perf-events for a given context or CPU.
> > >
> > > This patch exports these symbols so that they can be used by kernel
> > > modules. Without these symbols, an event must be destroyed and recreated
> > > to disable or enable it respectively. The maximum number of perf-events
> > > is also made available to modules via the perf_get_max_events function.
> > 
> > Where is the module that uses all this?
> 
> It's part of the same patchset:
> 
> http://lists.infradead.org/pipermail/linux-arm-kernel/2010-March/011126.html
> 
> The idea is to use perf-events as the backend for OProfile to avoid replicating
> the PMU accessor code.

Ah, very nice. Can something like that be done in general, like an
arch-independent oprofile backend using perf, or is there too much
arch-specific bits to the oprofile stuff?

I know Robert talked about doing something like this, I just have no
clue how arch specific this would be.