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Date: Fri, 29 Jun 2001 09:13:52 -0500
From: Vipin Malik <vipin.malik@daniel.com>
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To: David Woodhouse <dwmw2@infradead.org>
CC: Alan Cox <alan@lxorguk.ukuu.org.uk>,
 	jffs-dev <jffs-dev@axis.com>,
 	MTD for Linux <linux-mtd@lists.infradead.org>,
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Subject: Re: JFFS2 is broken
References: <E15Fu8H-0008JI-00@the-village.bc.nu>
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Alan Cox wrote:

>
> One thing you can do here is to wake the gc thread and sleep politely on it
>
> > The only solution, that I think will work, is to find a way to block the
> > write() to JFFS2 but allow kernel schedduling to go on. I really don't
> > know
>
> Well there are two things there.
>
> 1.      You could wake the GC and sleep on it  using sleep/wakeup or
>         semaphores
>
> 2.      Profile the kernel and find out where it is tight looping. I can't
>         see any reason for tight loops except for the compression itself
>         so it suggests a code bug.
>
> Finally within the compression loops you can check current->need_resched and
> if it is set call schedule() to allow the compression to switch to other
> tasks at the point it has used its time slice.

If David is already looking at this, maybe I'll wait for a few days before
bumbling through the code myself ;) David? You've been awfully quite!

Vipin