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Date: Sat, 14 Jan 2006 13:02:50 -0700
From: Scott Long <scottl@samsco.org>
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To: Suleiman Souhlal <ssouhlal@FreeBSD.org>
References: <20060114095318.GA39508@stud.fit.vutbr.cz>
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Cc: Divacky Roman <xdivac02@stud.fit.vutbr.cz>, current@FreeBSD.org
Subject: Re: sysenter patch question
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Suleiman Souhlal wrote:
> Scott Long wrote:
> 
>> I was the last to work on the patch, and that was about a year or so
>> ago.  It worked fine under fairly simple processes, but trying to run
>> things like KDE and Mozilla made it blow up fairly quickly.  I suspect
>> that it has something to do with thread upcalls, but I never got around
>> to figuring it out.  If someone wants to pick it up, that would be
>> great.  Note that this only matters for i386; amd64 has always had its
>> own version of sysenter that it uses.
> 
> 
> As far as I know, amd64 uses the SYSCALL instruction, which I believe, 
> should have about the same performance as SYSENTER.
> 
> --Suleiman
> 

Actually, the AMD SYSCALL command is a heck of a lot easier to use since 
it doesn't make as many assumptions about segment descriptors.

Scott