linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Matthew Wilcox <willy@infradead.org>
To: Jens Axboe <axboe@kernel.dk>
Cc: Al Viro <viro@zeniv.linux.org.uk>,
	Benjamin LaHaise <bcrl@kvack.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Kees Cook <keescook@chromium.org>,
	fsdevel <linux-fsdevel@vger.kernel.org>,
	linux-aio@kvack.org, linux-mm <linux-mm@kvack.org>,
	linux-kernel <linux-kernel@vger.kernel.org>,
	Dan Carpenter <dan.carpenter@oracle.com>
Subject: Re: [PATCH] aio: Convert ioctx_table to XArray
Date: Tue, 11 Dec 2018 10:53:11 -0800	[thread overview]
Message-ID: <20181211185311.GJ6830@bombadil.infradead.org> (raw)
In-Reply-To: <75267003-9407-101f-33ee-685e345a2c8a@kernel.dk>

On Tue, Dec 11, 2018 at 11:46:53AM -0700, Jens Axboe wrote:
> On 12/11/18 11:45 AM, Matthew Wilcox wrote:
> > I think we need the rcu read lock here to prevent ctx from being freed
> > under us by free_ioctx().
> 
> Then that begs the question, how about __xa_load() that is already called
> under RCU read lock?

I've been considering adding it to the API, yes.  I was under the
impression that nested rcu_read_lock() calls were not expensive, even
with CONFIG_PREEMPT.

  reply	other threads:[~2018-12-11 18:53 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-11-28 18:35 [PATCH] aio: Convert ioctx_table to XArray Matthew Wilcox
2018-12-06 21:08 ` Matthew Wilcox
2018-12-06 22:21 ` Jeff Moyer
2018-12-06 22:26   ` Jeff Moyer
2018-12-11 17:21     ` Jeff Moyer
2018-12-11 17:51       ` Matthew Wilcox
2018-12-11 18:02         ` Jeff Moyer
2018-12-11 18:05           ` Jens Axboe
2018-12-11 18:09             ` Jeff Moyer
2018-12-11 18:37               ` Jens Axboe
2018-12-11 18:32             ` Jens Axboe
2018-12-11 18:36               ` Jens Axboe
2018-12-11 18:51               ` Matthew Wilcox
2018-12-11 18:52                 ` Jens Axboe
2018-12-11 18:41 ` Jens Axboe
2018-12-11 18:45   ` Matthew Wilcox
2018-12-11 18:46     ` Jens Axboe
2018-12-11 18:53       ` Matthew Wilcox [this message]
2018-12-11 18:54         ` Jens Axboe
2018-12-11 18:53       ` Jens Axboe

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=20181211185311.GJ6830@bombadil.infradead.org \
    --to=willy@infradead.org \
    --cc=akpm@linux-foundation.org \
    --cc=axboe@kernel.dk \
    --cc=bcrl@kvack.org \
    --cc=dan.carpenter@oracle.com \
    --cc=keescook@chromium.org \
    --cc=linux-aio@kvack.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=viro@zeniv.linux.org.uk \
    /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).