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Date: Tue, 26 Aug 2008 14:49:02 +0200
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-core] xnregistry_fetch & friends
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To: Jan Kiszka <jan.kiszka@domain.hid>
Cc: xenomai-core <xenomai@xenomai.org>

Jan Kiszka wrote:
> BTW, I'm also preparing a patch to overcome hash chain registrations for
> anonymous (handle-only) objects as I need more of them (one for each
> thread) for fast mutexes - to avoid fiddling with kernel pointers in
> userland.

Ok. You will have a problem mangling a registry handle with the claimed
bit. Or maybe we can assume that the bit 31 is not used or something ?

And by the way, I had an idea of removing the duplication of the owner
field between an xnsynch and a mutex object, this would allow saving a
syscall when a situation of mutex stealing happened. Using a handle
would prevent this. But I am not so sure it is a good idea now (namely
because it would move some compare-and-swap the owner logic to the
xnsynch API).

-- 
                                                 Gilles.