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Date: Mon, 10 Jul 2006 15:53:21 +1000
From: Nathan Scott <nathans@sgi.com>
To: Milton Miller <miltonm@bga.com>
Cc: Jens Axboe <axboe@suse.de>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] blktrace: readahead support
Message-ID: <20060710155321.B1675237@wobbly.melbourne.sgi.com>
References: <200607100546.k6A5k3qU049783@sullivan.realtime.net>
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In-Reply-To: <200607100546.k6A5k3qU049783@sullivan.realtime.net>; from miltonm@bga.com on Mon, Jul 10, 2006 at 12:46:03AM -0500
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On Mon, Jul 10, 2006 at 12:46:03AM -0500, Milton Miller wrote:
> > +#define trace_ahead_bit(rw)	\
> > +	(((rw) & (1 << BIO_RW_AHEAD)) << (BIO_RW_AHEAD - 0))
> ...
> I think the shift should be << (2 - BIO_RW_AHEAD).

Quite possibly.  As long as it ends up in slot 4 in that array still..
which it will.

cheers.

-- 
Nathan