From owner-freebsd-current  Tue Dec  2 10:09:12 1997
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To: current@FreeBSD.ORG
Subject: Re: cvs commit: src/sys/kern vfs_aio.c 
In-reply-to: Your message of "Tue, 02 Dec 1997 09:06:20 PST."
             <199712021706.JAA28517@kithrup.com> 
Date: Tue, 02 Dec 1997 19:07:04 +0100
Message-ID: <2923.881086024@critter.freebsd.dk>
From: Poul-Henning Kamp <phk@critter.freebsd.dk>
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>>And yes, the reason is performance.
>
>Then you should back the changes out IMMEDIATELY, as
>
>	*retval = 10;
>
>is exactly the same speed as:
>
>	p->p_retval[0] = 10;

BZZZTT!   Wrong answer.

We save the time it takes to push the &retval on the stack on ALL syscalls.

--
Poul-Henning Kamp             FreeBSD coreteam member
phk@FreeBSD.ORG               "Real hackers run -current on their laptop."