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Date: Mon, 30 Jul 2012 10:00:13 -0700
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Mikulas Patocka <mpatocka@redhat.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>, Jens Axboe <axboe@kernel.dk>,
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        lwoodman@redhat.com, "Alasdair G. Kergon" <agk@redhat.com>
Subject: Re: [dm-devel] [PATCH 2/3] Introduce percpu rw semaphores
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On Sun, Jul 29, 2012 at 01:13:34AM -0400, Mikulas Patocka wrote:
> On Sat, 28 Jul 2012, Eric Dumazet wrote:
> > On Sat, 2012-07-28 at 12:41 -0400, Mikulas Patocka wrote:

[ . . . ]

> > (bdev->bd_block_size should be read exactly once )
> 
> Rewrite all direct and non-direct io code so that it reads block size just 
> once ...

For whatever it is worth, the 3.5 Linux kernel only has about ten mentions
of bd_block_size, at least according to cscope.

							Thanx, Paul