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Subject: Re: mprotect() api overhead.
To: Tony.P.Lee@nokia.com
Date: Sat, 23 Mar 2002 02:20:37 +0000 (GMT)
Cc: alan@lxorguk.ukuu.org.uk, linux-kernel@vger.kernel.org
In-Reply-To: <4D7B558499107545BB45044C63822DDE3A2047@mvebe001.NOE.Nokia.com> from "Tony.P.Lee@nokia.com" at Mar 22, 2002 05:59:59 PM
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From: Alan Cox <alan@lxorguk.ukuu.org.uk>
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> As for SMP case, for my application, it is less an issue, since
> when user call my API in the .so, the mprotect (or that HP=20
> 7 instructions) will open access to the share memory for them
> regardless which CPU they are coming from.  If other thread

That still requires cross processor synchronization - so it will still
take the same hit

Alan

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