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To: Konstantin Belousov <kostikbel@gmail.com>
Subject: Re: Removal of kern_xxx() no-at variants. 
In-reply-to: <20141112132451.GM17068@kib.kiev.ua> 
Date: Wed, 12 Nov 2014 12:23:29 -0800
From: Kirk McKusick <mckusick@mckusick.com>
Cc: arch@freebsd.org, fs@freebsd.org
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On Wednesday, November 12, 2014 8:24:52 am Konstantin Belousov wrote:

> We have 'fat' KPI for kern_open() and other vfs syscall helpers, after
> the at-version of the syscalls was added somewhere at 8-CURRENT.
> For instance, we provide
>       kern_open() and kern_openat().
> But more, we provide
>       kern_stat()
>       kern_lstat()
>       kern_statat()
>       kern_statat_vhook()
> first three being a trivial wrapper around kern_statat_vhook().
> More, existence of two or (sometimes) three layers around basic
> syscall helper causes issues like r271655 making the argument
> validation split.
>
> Kepping the compat layer was reasonable in 8-CURRENT time when the
> at variants were experimental and patch to add the syscalls was
> already large and error-prone.  Now, I think we should shave the
> extra call indirections, it costs nothing at callers and sometimes
> even improves the code.

I think this is an excellent idea and helps maintain the FreeBSD
philosophy of keeping its code base clean. I have reviewed the diffs 
and they all look good.

	Kirk McKusick