linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jeff Moyer <jmoyer@redhat.com>
To: Jan Kara <jack@suse.cz>
Cc: Nick Piggin <npiggin@gmail.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	linux-kernel@vger.kernel.org
Subject: Re: [patch] fs: aio fix rcu lookup
Date: Wed, 19 Jan 2011 14:46:27 -0500	[thread overview]
Message-ID: <x49aaiwd6cs.fsf@segfault.boston.devel.redhat.com> (raw)
In-Reply-To: <x49ei88d7vl.fsf@segfault.boston.devel.redhat.com> (Jeff Moyer's message of "Wed, 19 Jan 2011 14:13:34 -0500")

Jeff Moyer <jmoyer@redhat.com> writes:

> Jan Kara <jack@suse.cz> writes:
>
>>  But there's the second race I describe making it possible
>> for new IO to be created after io_destroy() has waited for all IO to
>> finish...
>
> Can't that be solved by introducing memory barriers around the accesses
> to ->dead?

Upon further consideration, I don't think so.

Given the options, I think adding the synchronize rcu to the io_destroy
path is the best way forward.  You're already waiting for a bunch of
queued I/O to finish, so there is no guarantee that you're going to
finish that call quickly.

Cheers,
Jeff

  reply	other threads:[~2011-01-19 19:46 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-01-14  1:35 [patch] fs: aio fix rcu lookup Nick Piggin
2011-01-14 14:52 ` Jeff Moyer
2011-01-14 15:00   ` Nick Piggin
2011-01-17 19:07     ` Jeff Moyer
2011-01-17 23:24       ` Nick Piggin
2011-01-18 17:21         ` Jeff Moyer
2011-01-18 19:01         ` Jan Kara
2011-01-18 22:17           ` Nick Piggin
2011-01-18 23:00             ` Jeff Moyer
2011-01-18 23:05               ` Nick Piggin
2011-01-18 23:52             ` Jan Kara
2011-01-19  0:20               ` Nick Piggin
2011-01-19 13:21                 ` Jan Kara
2011-01-19 16:03                   ` Nick Piggin
2011-01-19 16:50                     ` Jan Kara
2011-01-19 17:37                       ` Nick Piggin
2011-01-20 20:21                         ` Jan Kara
2011-01-19 19:13                   ` Jeff Moyer
2011-01-19 19:46                     ` Jeff Moyer [this message]
2011-01-19 20:18                       ` Nick Piggin
2011-01-19 20:32                         ` Jeff Moyer
2011-01-19 20:45                           ` Nick Piggin
2011-01-19 21:03                             ` Jeff Moyer
2011-01-19 21:20                               ` Nick Piggin
2011-01-20  4:03                                 ` Paul E. McKenney
2011-01-20 18:31                                   ` Nick Piggin
2011-01-20 20:02                                     ` Paul E. McKenney
2011-01-20 20:15                                       ` Eric Dumazet
2011-01-21 21:22                                         ` Paul E. McKenney
2011-01-20 20:16                                     ` Jan Kara
2011-01-20 21:16                                       ` Jeff Moyer
2011-02-01 16:24                                       ` 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=x49aaiwd6cs.fsf@segfault.boston.devel.redhat.com \
    --to=jmoyer@redhat.com \
    --cc=akpm@linux-foundation.org \
    --cc=jack@suse.cz \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=npiggin@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).