linux-ext4.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Ted Ts'o <tytso@mit.edu>
To: Jan Kara <jack@suse.cz>
Cc: Manish Katiyar <mkatiyar@gmail.com>,
	linux-ext4@vger.kernel.org, mfasheh@suse.com, jlbec@evilplan.org
Subject: Re: [PATCH v2 2/3] jbd2: Add extra parameter in start_this_handle() to control allocation flags.
Date: Tue, 31 May 2011 18:27:20 -0400	[thread overview]
Message-ID: <20110531222720.GA3867@thunk.org> (raw)
In-Reply-To: <20110531112253.GD5614@quack.suse.cz>

On Tue, May 31, 2011 at 01:22:53PM +0200, Jan Kara wrote:
> 
> The problem is that with ext4, we need i_mutex in io completion path to
> end page writeback. So we cannot do GFP_KERNEL allocation whenever we hold
> i_mutex because mm might wait in direct reclaim for IO to complete and that
> cannot happen until we release i_mutex. 

OK, maybe I'm being dense, but I'm not seeing it.  I see where we need
i_mutex on the ext4_da_writepages() codepath, but that's never used
for direct reclaim.  Direct reclaim only calls ext4_writepage(), and
that doesn't seem to try to grab i_mutex as near as I can tell.  Am I
missing something?

						- Ted

  reply	other threads:[~2011-06-01  2:22 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-05-28  6:16 [PATCH v2 1/3] ext4: Fix missing acl release in error path in acl.c Manish Katiyar
2011-05-28  6:20 ` [PATCH v2 2/3] jbd2: Add extra parameter in start_this_handle() to control allocation flags Manish Katiyar
2011-05-31 11:22   ` Jan Kara
2011-05-31 22:27     ` Ted Ts'o [this message]
2011-06-02  9:54       ` Jan Kara
2011-06-06  0:12         ` Manish Katiyar
2011-06-06  3:21         ` Ted Ts'o
2011-06-08 14:10           ` Ted Ts'o
2011-06-17  6:32             ` Manish Katiyar
2011-06-20 14:32               ` Jan Kara
2011-06-20 14:40                 ` Manish Katiyar
2011-06-20 17:57                   ` Ted Ts'o
2011-06-20 18:08                     ` Manish Katiyar
2011-05-28  6:21 ` [PATCH v2 3/3] ext4: Fix ext4 to use pass jbd allocation flags if they can handle ENOMEM Manish Katiyar
2011-05-31 12:10   ` Jan Kara

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=20110531222720.GA3867@thunk.org \
    --to=tytso@mit.edu \
    --cc=jack@suse.cz \
    --cc=jlbec@evilplan.org \
    --cc=linux-ext4@vger.kernel.org \
    --cc=mfasheh@suse.com \
    --cc=mkatiyar@gmail.com \
    /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;
as well as URLs for NNTP newsgroup(s).