Re: [PATCH] perf: Don't schedule tracepoints when exclude_kernel isset

From: Ingo Molnar
Date: Sat Apr 09 2011 - 09:17:22 EST



* Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> wrote:

> On Fri, 2011-04-08 at 22:57 +0200, Frederic Weisbecker wrote:
> > Instead of checking attr.exclude_kernel anytime a tracepoint
> > event triggers, simply don't schedule the tracepoint it that
> > attribute is set. This makes one test less in the tracing
> > path.
>
> Meh, I'd much rather someone spend some time on finishing the below,
> which is a much bigger improvement for trace-events.
>
> ---
> Subject: perf: Tracepoint collection support
> From: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
> Date: Sat Nov 20 18:09:34 CET 2010
>
> Due to popular demand this implements a tracepoint collection event
> { .type = PERF_TYPE_TRACEPOINT, .config = ~0ULL }. by default it
> contains no tracepoints, but tracepoints can be added using:
> ioctl(fd, PERF_EVENT_IOC_ADD_TP, tp_id);

+1 !!!

This is like a super-important feature.

Thanks,

Ingo
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