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Date: Fri, 12 Feb 2010 17:03:20 +0100
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-core] Yet another ((weak)) bug
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To: Jan Kiszka <jan.kiszka@domain.hid>
Cc: xenomai-core <xenomai@xenomai.org>

Jan Kiszka wrote:
> Gilles Chanteperdrix wrote:
>> Jan Kiszka wrote:
>>> Hi Gilles,
>>>
>>> this one requires some fixing too:
>>>
>>> xeno_sem_heap is marked weak. xeno_init_sem_heaps is called once per
>>> initialized skin. It unmaps any existing heap and creates a new one.
>>> That's already fragile during constructor run, but it's lethal during
>>> process runtime, ie. when using dlopen.
>>>
>>> I think the solution is to handle forks separately and only remap in
>>> that case. Digging in this direction now.
>>>
>>> BTW, what triggers the re-run of xeno_init_sem_heaps after a fork so far?
>> It must be done for the child process to get a private heap different
>> from the parent process. I would guess it is handled by pthread_atfork.
> 
> Ah, only the POSIX skin does that. However, sem-heaps must not be
> POSIX-only. OK, patch in the make.

Ok. I am thinking more and more that you are right about making
libxeno_common a standalone library. Only the name stinks, we should
find a better one.


-- 
					    Gilles.