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From: David Woodhouse <dwmw2@infradead.org>
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To: andreev <andreev@niisi.msk.ru>
Cc: "linux-mtd@lists.infrared.org" <linux-mtd@lists.infradead.org>
Subject: Re: Why timer interrupt is disabled? 
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andreev@niisi.msk.ru said:
> <br><br></pre></blockquote> I know that JFFS is the better choice, but
> I must use the FTL driver, because there is installed X-server on my 
> flash <br> partition... <br>

I don't see the logic. The Compaq iPAQ works quite well with the X-server 
in the JFFS2 filesystem.


>  <br> I think that unlocking of the io_request_lock inside ftl driver
> is not a good idea, because the do_ftl_request must be <br> atomic.

My understanding is that it's perfectly safe to drop the io_request_lock
as long as we only look at the request at the head of the queue. There's no 
need for do_ftl_request to be atomic - and in fact it cannot be atomic 
because the flash read and write calls may sleep.

> What about enabling all or only <br> timer interrupts inside
> do_ftl_request. Can you uncomment the sti() in ftl.c in your CVS
> version?<br> <br> <br> </body></html>

If you ensure that it's correct to do so, and provide a patch which 
releases the io_request_lock, then I'll certainly consider applying it.

--
dwmw2