Re: perf: prctl(PR_TASK_PERF_EVENTS_DISABLE) has no effect

[Ingo Molnar]

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

> On Mon, 2012-01-30 at 11:11 +0100, Ingo Molnar wrote:
> > So, what workflow are you suggesting to Andrew?
> 
> Librarize perf record, then in your code do something like:
> 
> #include "perf_record.h"

Maybe. (and then it shouldnt be limited to perf_record.h but 
should be events.h plus libevents.so or such)

> 
>   handle = perf_record_init(); /* creates perf events and creates
>                                   a record thread that writes samples
>                                   to perf.data, consumes env(PERF_*)
>                                   for configuration, registers with
>                                   at_exit() for cleanup */
>   if (!handle)
>     /* burn */
> 
>   /* do you other code */
> 
>   perf_record_start(handle);
> 
>   /* do the bit you want profiled */
> 
>   perf_record_stop(handle);
> 
> Then build with -lperfrecord or so. Not too hard, right?

Isnt a simple prctl() so much easier and faster?

What's your concern with the prctl()? This would arguably be the 
right kind of usage for prctl(): it's an established API/ABI for 
process/task-wide settings.

Thanks,

	Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/