From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Thu, 29 Jan 2009 16:56:26 +0100
From: Jan Kiszka <jan.kiszka@domain.hid>
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Subject: Re: [Xenomai-help] interrupt service routine issue
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Cc: "xenomai@xenomai.org" <xenomai@xenomai.org>

Gilles Chanteperdrix wrote:
> stefano.franzoni@domain.hid wrote:
>> Thanks Gilles,
>>
>> with your suggestion, setting the special mode bit T_WARNSW for the
>> incriminated task, we found two critical functions that caused switches to
>> secondary mode.
>>
>> I report them for documentation:
>>
>> 1. We used mmap function used to map a file into memory. The access to the
>> memory caused sometimes the switch to secondary mode.
> 
> damn, this should not happen, we use mlockall and some additional tricks
> in the I-pipe patch to avoid that.

Mmmh, I don't think we can cure (/wrt RT) access to memory mapped files.
That's just the same no-go for RT threads as other Linux I/O.

Jan

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