From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Fri, 19 Jan 2007 10:22:23 +0100
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-core] Nocow patch.
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Gilles Chanteperdrix wrote:
> However, after looking at the ARM patch, I am not so sure
> __ipipe_update_all_pinned_mm() is the way to go on all architectures.
> The ARM I-pipe handles vmalloc and ioremap faults without causing a mode
> switch, I wonder if it is not better than having
> __ipipe_update_all_pinned_mm() updating page directories all over the
> place.

I checked with the I-pipe tracer the overhead on an ARM of a fault on a
vmalloced area: it costs around 5 us.

-- 
                                                 Gilles Chanteperdrix