From: Andrew Morton <akpm@osdl.org>
To: Jan Kara <jack@ucw.cz>
Cc: linux-kernel@vger.kernel.org, crosser@average.org
Subject: Re: Deadlock problems
Date: Mon, 3 May 2004 11:14:56 -0700 [thread overview]
Message-ID: <20040503111456.5d7ea77c.akpm@osdl.org> (raw)
In-Reply-To: <20040503115837.GC360@atrey.karlin.mff.cuni.cz>
Jan Kara <jack@ucw.cz> wrote:
>
> Hi Andrew!
>
> I've found hard to fix problem causing deadlock - call path is
> generally following:
> some operation -> quota code -> read/write quota -> vfs -> needs a page ->
> shrink caches -> free inodes -> free quota -> Ouch... (we need to acquire
> some lock which is already held by the quota code)
>
> I hope I can fix the problems with quota locks but there's also a
> problem that transaction can be already started when we want to free
> some inodes etc.
yes, there could be any number of deadlocks due to this.
> So I'd like to ask: Is there somewhere documented what
> can/cannot hold a caller using GFP_FS?
I don't understand the question, sorry. But memory allocations while
holding fs locks should not be using __GFP_FS.
> One a bit hacky solution would also be to clear GFP_FS from i_mapping
> of quotafile inode. Do you think that is a reasonable solution?
yes, I think that is a reasonable expression of what is going on.
It would be better to rework the filesystems so that it is not necessary,
but I assume that is complex.
prev parent reply other threads:[~2004-05-03 18:15 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-05-03 11:58 Deadlock problems Jan Kara
2004-05-03 13:11 ` Chris Mason
2004-05-03 18:14 ` Andrew Morton [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20040503111456.5d7ea77c.akpm@osdl.org \
--to=akpm@osdl.org \
--cc=crosser@average.org \
--cc=jack@ucw.cz \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox