From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mathieu Desnoyers <mathieu.desnoyers-vg+e7yoeK/dWk0Htik3J/w@public.gmane.org>
Subject: Re: [RFC PATCH] getcpu_cache system call: caching current CPU
 number (x86)
Date: Sat, 18 Jul 2015 02:43:25 +0000 (UTC)
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----- On Jul 17, 2015, at 6:43 PM, Ond=C5=99ej B=C3=ADlka neleai@seznam=
=2Ecz wrote:

> On Fri, Jul 17, 2015 at 04:03:30PM +0000, Mathieu Desnoyers wrote:
>> ----- On Jul 17, 2015, at 6:58 AM, Ond=C5=99ej B=C3=ADlka neleai@sez=
nam.cz wrote:
>> [...]
>> >> If we invoke this per-thread registration directly in the glibc N=
PTL
>> >> implementation,
>> >> in start_thread, do you think it would fit your requirements ?
>> >>
>
[...]
>> > Second would be write patch to libc adding function
>> > pthread_create_add_hook_np to register function that would be ran =
after
>> > each thread creation.
>>=20
>> Do you suggest that this callback should be registered once per thre=
ad,
>> or somehow attached to pthread_attr_t ? As maintainer of lttng-ust,
>> where we need some control over our own threads, but where we want m=
inimal
>> impact on the overall application, I would really prefer if we can a=
ttach
>> the callback to pthread_attr_t.
>>=20
> Could you elaborate. I was suggesting per-thread callback, what do yo=
u
> want to do with pthread_attr_t?

Hrm, nevermind, even in the context of lttng-ust, I'd want the callback=
 to
be called for every thread in the application. Therefore, registering t=
his
callback once per process seems to make sense.

Thanks,

Mathieu

--=20
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com