From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCHv2 04/11] writeback: do not lose wake-ups in the forker
 thread - 2
Date: Wed, 21 Jul 2010 07:57:25 -0400
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Cc: Jens Axboe <axboe@kernel.dk>, linux-fsdevel@vger.kernel.org,
	linux-kernel@vger.kernel.org
To: Artem Bityutskiy <dedekind1@gmail.com>
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On Wed, Jul 21, 2010 at 12:31:39PM +0300, Artem Bityutskiy wrote:
> From: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
> 
> Currently, if someone submits jobs for the default bdi, we can lose wake-up
> events. E.g., this can happen if 'bdi_queue_work()' is called when
> 'bdi_forker_thread()' is executing code after 'wb_do_writeback(me, 0)', but
> before 'set_current_state(TASK_INTERRUPTIBLE)'.
> 
> This situation is unlikely, and the result is not very severe - we'll just
> delay the execution of the work, but this is still not very nice.
> 
> This patch fixes the issue by checking whether the default bdi has works before
> the forker thread goes sleep.

Looks good,


Reviewed-by: Christoph Hellwig <hch@lst.de>