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Date: Tue, 11 Jul 2006 20:52:45 +0100
From: Russell King <rmk+lkml@arm.linux.org.uk>
To: Jon Smirl <jonsmirl@gmail.com>
Cc: Theodore Tso <tytso@mit.edu>, Alan Cox <alan@lxorguk.ukuu.org.uk>,
       lkml <linux-kernel@vger.kernel.org>
Subject: Re: tty's use of file_list_lock and file_move
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On Mon, Jul 10, 2006 at 11:33:18PM -0400, Jon Smirl wrote:
> I tried changing it to a per tty spinlock. Now I know that the code
> relies on the BKL being broken when a task sleeps.

Not broken - it's unlocked only for the duration of the sleep.  To put
it another way, the BKL is dropped by the scheduler prior to switching
away, and is reacquired by the scheduler when resuming a thread which
previously was BKL-locked.

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:  2.6 Serial core