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Message-Id: <19970609112746.28225@mi.uni-koeln.de>
Date: Mon, 9 Jun 1997 11:27:46 +0200
From: Stefan Esser <se@FreeBSD.ORG>
To: Bruce Evans <bde@FreeBSD.ORG>
Cc: cvs-committers@FreeBSD.ORG, cvs-all@FreeBSD.ORG, cvs-sys@FreeBSD.ORG,
        Stefan Esser <se@FreeBSD.ORG>
Subject: Re: cvs commit: src/sys/i386/include md_var.h pcb.h reg.h src/sys/i386/i386 genassym.c machdep.c swtch.s trap.c
References: <199706070436.VAA21703@freefall.freebsd.org>
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In-Reply-To: <199706070436.VAA21703@freefall.freebsd.org>; from Bruce Evans on Fri, Jun 06, 1997 at 09:36:11PM -0700
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On Jun 6, Bruce Evans <bde@freebsd.org> wrote:
>   Preserve %fs and %gs across context switches.  This has a relatively low
>   cost since it is only done in cpu_switch(), not for every exception.
>   The extra state is kept in the pcb, and handled much like the npx state,
>   with similar deficiencies (the state is not preserved across signal
>   handlers, and error handling loses state).

I asked about plans to add saving of FS and GS
for improved Wine support, some time ago, and I 
got the answer, it was a waste to do this just 
for that one program.

Seems that either 1) there now is something more
important that requires those registers to be 
preserved, or 2) the overhead is not *that* high,
after all :)

Just curious ...

Regards, STefan