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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: Jeff Roberson <jroberson@jroberson.net>
References: <alpine.BSF.2.00.0905111720280.981@desktop>
Date: Tue, 12 May 2009 13:02:49 +0200
In-Reply-To: <alpine.BSF.2.00.0905111720280.981@desktop> (Jeff Roberson's
	message of "Mon, 11 May 2009 17:32:17 -1000 (HST)")
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Cc: arch@freebsd.org
Subject: Re: lockless file descriptor lookup
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Jeff Roberson <jroberson@jroberson.net> writes:
> I'd also appreciate it if someone could look at my volatile cast and
> make sure I'm actually forcing the compiler to refresh the fd_ofiles
> array here:
>
> +		if (fp =3D=3D ((struct file *volatile*)fdp->fd_ofiles)[fd])

The problem is that since it is not declared as volatile, some other
piece of code may have modified it but not yet flushed it to RAM.

DES
--=20
Dag-Erling Sm=C3=B8rgrav - des@des.no