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Date: Tue, 14 Oct 2008 11:41:40 +0200
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-core] __thread instead of pthread_get/setspecific
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To: Jan Kiszka <jan.kiszka@domain.hid>
Cc: xenomai-core <xenomai@xenomai.org>

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.

-- 
                                                 Gilles.