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Message-ID: <4836E057.7020307@yandex.ru>
Date: Fri, 23 May 2008 18:18:47 +0300
From: Artem Bityutskiy <dedekind@yandex.ru>
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To: Christoph Hellwig <hch@infradead.org>
CC: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>,
       LKML <linux-kernel@vger.kernel.org>,
       Adrian Hunter <ext-adrian.hunter@nokia.com>
Subject: Re: [PATCH take 2] UBIFS - new flash file system
References: <1210070159-22794-1-git-send-email-Artem.Bityutskiy@nokia.com> <20080516104002.GA6962@infradead.org>
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Christoph Hellwig wrote:
>  - the mainoop of ubifs_bg_thread looks a bit odd either, when you
>    first to an interruotible sleep and then possible one while you
>    still have TASK_RUNNING set.  Also the need_bgt flag is not needed
>    because the thrad is only woken up to perform it's action.
>    In the end the main loop should look something like:
> 
> 	while (1) {
> 		if (kthread_should_stop())
> 			break;
> 		if (try_to_freeze())
> 			continue;
> 
> 		run_bg_commit(c);
> 
> 		set_current_state(TASK_INTERRUPTIBLE);
> 		schedule();
> 		__set_current_state(TASK_RUNNING);
> 	}

Err, how are we guaranteed that we do not miss wake-up events then,
if we were woken up say, between run_bg_commit(c) and
set_current_state(TASK_INTERRUPTIBLE) ? This was  the purpose
of the 'need_bgt' flag.

-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)