From: Jens Axboe <axboe@kernel.dk>
To: Matthew Wilcox <willy@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>,
Linus Torvalds <torvalds@linux-foundation.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH 1/2] fs: add support for LOOKUP_NONBLOCK
Date: Fri, 11 Dec 2020 11:55:46 -0700 [thread overview]
Message-ID: <b496fc38-908b-d3e7-4506-f0b0d6f7b60c@kernel.dk> (raw)
In-Reply-To: <20201211173305.GB2443@casper.infradead.org>
On 12/11/20 10:33 AM, Matthew Wilcox wrote:
> On Fri, Dec 11, 2020 at 09:05:26AM -0700, Jens Axboe wrote:
>> On 12/10/20 7:45 PM, Al Viro wrote:
>>> So how hard are your "we don't want to block here" requirements? Because
>>> the stuff you do after complete_walk() can easily be much longer than
>>> everything else.
>>
>> Ideally it'd extend a bit beyond the RCU lookup, as things like proc
>> resolution will still fail with the proposed patch. But that's not a
>> huge deal to me, I consider the dentry lookup to be Good Enough.
>
> FWIW, /proc/$pid always falls back to REF walks. Here's a patch from
> one of my colleagues that aims to fix that.
>
> https://lore.kernel.org/linux-fsdevel/20201204000212.773032-1-stephen.s.brennan@oracle.com/
>
> Maybe you had one of the other parts of /proc in mind?
Yes, it is/was /proc/self/ specifically, which the patch won't really
help. But it's not like it's a huge issue, and I'm quite happy (for
now) to just have that -EOPNOTSUPP on open as it does.
--
Jens Axboe
next prev parent reply other threads:[~2020-12-11 20:41 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-10 20:01 [PATCHSET 0/2] fs: Support for LOOKUP_NONBLOCK / RESOLVE_NONBLOCK Jens Axboe
2020-12-10 20:01 ` [PATCH 1/2] fs: add support for LOOKUP_NONBLOCK Jens Axboe
2020-12-10 20:53 ` Linus Torvalds
2020-12-10 21:06 ` Jens Axboe
2020-12-11 2:45 ` Al Viro
2020-12-11 16:05 ` Jens Axboe
2020-12-11 17:20 ` Al Viro
2020-12-11 17:35 ` Linus Torvalds
2020-12-11 18:50 ` Jens Axboe
2020-12-11 21:51 ` Al Viro
2020-12-11 23:47 ` Jens Axboe
2020-12-11 17:33 ` Matthew Wilcox
2020-12-11 18:55 ` Jens Axboe [this message]
2020-12-11 2:35 ` Al Viro
2020-12-11 15:57 ` Jens Axboe
2020-12-11 17:21 ` Linus Torvalds
2020-12-11 17:29 ` Al Viro
2020-12-11 17:38 ` Al Viro
2020-12-11 17:44 ` Linus Torvalds
2020-12-11 21:46 ` Jens Axboe
2020-12-10 20:01 ` [PATCH 2/2] fs: expose LOOKUP_NONBLOCK through openat2() RESOLVE_NONBLOCK Jens Axboe
2020-12-10 22:29 ` Dave Chinner
2020-12-10 23:12 ` Jens Axboe
2020-12-10 23:29 ` Linus Torvalds
2020-12-11 0:58 ` Dave Chinner
2020-12-11 1:01 ` Linus Torvalds
2020-12-11 3:45 ` Dave Chinner
2020-12-11 18:07 ` Linus Torvalds
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=b496fc38-908b-d3e7-4506-f0b0d6f7b60c@kernel.dk \
--to=axboe@kernel.dk \
--cc=linux-fsdevel@vger.kernel.org \
--cc=torvalds@linux-foundation.org \
--cc=viro@zeniv.linux.org.uk \
--cc=willy@infradead.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.