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Date: Tue, 10 Dec 2002 11:08:41 +0000
From: Jamie Lokier <lk@tantalophile.demon.co.uk>
To: Linus Torvalds <torvalds@transmeta.com>
Cc: george anzinger <george@mvista.com>, Jim Houston <jim.houston@ccur.com>,
       Stephen Rothwell <sfr@canb.auug.org.au>,
       LKML <linux-kernel@vger.kernel.org>, anton@samba.org,
       "David S. Miller" <davem@redhat.com>, ak@muc.de, davidm@hpl.hp.com,
       schwidefsky@de.ibm.com, ralf@gnu.org, willy@debian.org
Subject: Re: [PATCH] compatibility syscall layer (lets try again)
Message-ID: <20021210110841.GA15418@bjl1.asuk.net>
References: <3DEEB37A.233DD280@mvista.com> <Pine.LNX.4.44.0212041830100.3100-100000@home.transmeta.com>
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Linus Torvalds wrote:
> So what we do is to introduce a _new_ system call 
> (system call number NNN), which takes a different form of timeout, namely 
> "absolute value of end time".

An "absolute value of end time" variant of
select/poll/epoll/io_getevents would be good anyway from userspace, to
avoid the gettimeofday+poll race condition.

So, perhaps the solution here is to simply provide absolute time
variants of the system calls which currently take time delays, and
have the relative-time variants rewrite themselves into absolute form?

That's architecture neutral _and_ fixes a long-standing race
condition..

-- Jamie
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