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Date: Tue, 6 May 2008 10:01:26 +0900
From: "KOSAKI Motohiro" <kosaki.motohiro@jp.fujitsu.com>
To: "Rik van Riel" <riel@redhat.com>
Subject: Re: [-mm][PATCH 4/5] core of reclaim throttle
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> > hmmm, AFAIK,
>  > on current kernel, sometimes __GFP_IO task wait for non __GFP_IO task
>  > by lock_page().
>  > Is this wrong?
>
>  This is fine.
>
>  The problem is adding a code path that causes non __GFP_IO tasks to
>  wait on __GFP_IO tasks.  Then you can have a deadlock.

Ah, OK.
I'll add __GFP_FS and __GFP_IO check at next post.

Thanks!


>  > therefore my patch care only recursive reclaim situation.
>  > I don't object to your opinion. but I hope understand exactly your opinion.
>
>  I believe not all non __GFP_IO or non __GFP_FS calls are recursive
>  reclaim, but there are some other code paths too.  For example from
>  fs/buffer.c

absolutely.