Re: [PATCH RFC -tip 0/6] perf: IRQ-bound performance events

[Jiri Olsa <jolsa@redhat.com>]

On Mon, Jun 03, 2013 at 09:41:21PM +0200, Frederic Weisbecker wrote:
> On Mon, Jun 03, 2013 at 02:22:23PM +0200, Ingo Molnar wrote:
> > 
> > * Alexander Gordeev <agordeev@redhat.com> wrote:

SNIP

> How about we define finegrained context on top of perf events themselves?
> Like we could tell perf to count a task's instructions only after
> tracepoint:irq_entry is hit and stop counting when tracepoint:irq_exit.
> 
> This way we can define any kind of fine grained context, not just irqs. We
> are not short on tracepoints, software events, breakpoints, kprobes, uprobes
> to play Legos there.

agreed, we could do the same as Alex did plus we'd have
the generic interface to meassure any place

> 
> I had a branch with a working draft of that:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
>   	perf/custom-ctx-v2-pre
> 
> Frederic Weisbecker (5):
>       perf: Starter and stopper events
>       perf: New enable_on_starter attribute
>       perf: Support for starter and stopper in tools
>       perf: New --enable-on-starter option
>       perf: Add TODOs for event defined context
> 
> It needs quite some improvements, (some are listed in the TODO on the last commit)
> especially in both the kernel and user interfaces.
> 
> Jiri had some nice ideas about it.

yep, one of them is to to get back to this soon ;-)

jirka