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Date: Wed, 31 Dec 2003 15:46:48 -0800
From: Andrew Morton <akpm@osdl.org>
To: Daniel McNeil <daniel@osdl.org>
Cc: suparna@in.ibm.com, janetmor@us.ibm.com, pbadari@us.ibm.com,
       linux-aio@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH linux-2.6.1-rc1-mm1] aiodio_fallback_bio_count.patch
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Daniel McNeil <daniel@osdl.org> wrote:
>
> This is an update of AIO fallback patch and with the bio_count race
>  fixed by changing bio_list_lock into bio_lock and using that for all
>  the bio fields.  I changed bio_count and bios_in_flight from atomics
>  into int.  They are now proctected by the bio_lock.  I fixed the race,
>  by in finished_one_bio() by leaving the bio_count at 1 until after the
>  dio_complete() and then do the bio_count decrement and wakeup holding
>  the bio_lock.

Sob.  Daniel, please assume that I have an extremely small brain and forget
things very easily.  And that 2,000 patches have passed under my nose since
last I contemplated the direct-io code, OK?

What bio_count race?

And the patch seems to be doing more than your description describes?