Re: [Xenomai-core] __thread instead of pthread_get/setspecific

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

Jan Kiszka wrote:
> Gilles Chanteperdrix wrote:
>> Jan Kiszka wrote:
>>> It will always remain orders of magnitude heavier than __thread
>>> variables which are a) inlined and b) should only need two memory
>>> accesses at worst. Moreover, it is clearly the future, while the
>>> importance of pthread_getspecific will decrease over the time. The
>>> __thread storage class is C99 standard (though its implementation
>>> remains a separate topic).
>> You are exagerating a bit: pthread_getspecific is pretty efficient
>> already (from the few things that I have timed on ARM, it is the only
>> one which takes under the microsecond). That you will gain something
>> with __thread is not guaranteed by the C99 standard either: in fact the
>> implementation could use exactly the same functions.
> 
> As long as we do not loose anything (performance or portability),

You loose portability. But I agree that we do not care much.

-- 
                                                 Gilles.