From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Mon, 10 Nov 2008 13:32:57 +0100
From: Wolfgang Grandegger <wg@domain.hid>
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Subject: Re: [Xenomai-help] Mode switch when using RT heap on ARM
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Cc: xenomai-help <xenomai@xenomai.org>

Gilles Chanteperdrix wrote:
> Wolfgang Grandegger wrote:
>> Hello,
>>
>> I realized that accessing memory allocated with rt_heap_alloc() causes
>> mode switches on ARM i.mx31. The attached patch provides a demo program
>> to demonstrate the problem, which actually does *not* show up on my
>> PowerPC TQM5200 board.
> 
> On ARM, we normally map the heaps uncacheable, this should not be
> necessary on ARMv6, but I am afraid we then get the fault on first access.

Is each cache-line of the heap not touched automatically when the heap
gets created? I thought it's necessary for other archs as well.

Wolfgang.