Re: [PATCH resend] Reading POSIX CPU timer from outside theprocess.

From: torbenh
Date: Thu Jan 06 2011 - 11:06:40 EST


On Tue, Jan 04, 2011 at 12:01:25PM +0100, Dario Faggioli wrote:
> On Thu, 2010-12-30 at 18:45 +0100, torbenh wrote:
> > > I think we should change glibc if clock_getcpuclockid() doesn't work,
> > > please see below.
> >
> > http://www.kernel.org/doc/man-pages/online/pages/man3/pthread_getcpuclockid.3.html
> >
> > this one works.
> > ok... it takes a pthread_t for identifying the thread.
> > but it works.
> >
> Well, I knew this, I knew it very well, as you can see from the code on
> the git I pointed to (it's part of one of the examples!).
>
> the thing is that I believe there are situations where it could be
> useful to sample CLOCK_THREAD_CPUTIME_ID from a _different_ process, and
> in that case, you can't access that thread's pthread-id, can you? :-O
>
> The jack2 code I saw could be one of these "potential user", and AFAICT
> your jack1 might be another one, no?
> Yeah, I know, whether you can/want use this or not also depends on other
> issues, but you are in a _different_ process --and thus you can't use
> pthread_* calls-- aren't you?

i would need to tell the tid to jackd anyways.
i could as well just communicate the clock_id.

getting the clock_id into the other process is not a problem.
the problem is that i am not allowed to read out the clock.


>
> I'm now looking at Oleg's solution and into glibc as well... I'll come
> out with something ASAP.
>
> Regards,
> Dario
>
> --
> <<This happens because I choose it to happen!>> (Raistlin Majere)
> ----------------------------------------------------------------------
> Dario Faggioli, ReTiS Lab, Scuola Superiore Sant'Anna, Pisa (Italy)
>
> http://retis.sssup.it/people/faggioli -- dario.faggioli@xxxxxxxxxx



--
torben Hohn
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