All of lore.kernel.org
 help / color / mirror / Atom feed
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	Network Development <netdev@vger.kernel.org>, LKP <lkp@01.org>
Subject: Re: [PATCH 6/6] fs: replace f_ops->get_poll_head with a static ->f_poll_head pointer
Date: Thu, 28 Jun 2018 17:13:26 -0700	[thread overview]
Message-ID: <CA+55aFxeZATKBRBsws=94BP8ZxsCv9HE9MBmwe-reuTVZFq=WQ@mail.gmail.com> (raw)
In-Reply-To: <20180628233720.GN30522@ZenIV.linux.org.uk>

On Thu, Jun 28, 2018 at 4:37 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> You underestimate the nastiness of that thing (and for the record, I'm
> a lot *less* fond of AIO than you are, what with having had to read that
> nest of horrors lately).  It does not "copy the data to userland"; what it
> does instead is copying into an array of pages it keeps, right from
> IO completion callback.  I

Ugh.

Oh well. I'd be perfectly happy to have somebody re-write and
re-architect the aio code entirely.  Much rather than that the
->poll() code. Because I know which one I think is well-desiged with a
nice usable interface, and which one is a pile of shit.

In the meantime, if AIO wants to do poll() in some irq callback, may I
suggest just using workqueues.

            Linus

WARNING: multiple messages have this Message-ID (diff)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: lkp@lists.01.org
Subject: Re: [PATCH 6/6] fs: replace f_ops->get_poll_head with a static ->f_poll_head pointer
Date: Thu, 28 Jun 2018 17:13:26 -0700	[thread overview]
Message-ID: <CA+55aFxeZATKBRBsws=94BP8ZxsCv9HE9MBmwe-reuTVZFq=WQ@mail.gmail.com> (raw)
In-Reply-To: <20180628233720.GN30522@ZenIV.linux.org.uk>

[-- Attachment #1: Type: text/plain, Size: 799 bytes --]

On Thu, Jun 28, 2018 at 4:37 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> You underestimate the nastiness of that thing (and for the record, I'm
> a lot *less* fond of AIO than you are, what with having had to read that
> nest of horrors lately).  It does not "copy the data to userland"; what it
> does instead is copying into an array of pages it keeps, right from
> IO completion callback.  I

Ugh.

Oh well. I'd be perfectly happy to have somebody re-write and
re-architect the aio code entirely.  Much rather than that the
->poll() code. Because I know which one I think is well-desiged with a
nice usable interface, and which one is a pile of shit.

In the meantime, if AIO wants to do poll() in some irq callback, may I
suggest just using workqueues.

            Linus

  reply	other threads:[~2018-06-29  0:13 UTC|newest]

Thread overview: 50+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-06-28 14:20 [RFC] replace ->get_poll_head with a waitqueue pointer in struct file Christoph Hellwig
2018-06-28 14:20 ` Christoph Hellwig
2018-06-28 14:20 ` [PATCH 1/6] net: remove sock_poll_busy_flag Christoph Hellwig
2018-06-28 14:20   ` Christoph Hellwig
2018-06-28 14:20 ` [PATCH 2/6] net: remove bogus RCU annotations on socket.wq Christoph Hellwig
2018-06-28 14:20   ` Christoph Hellwig
2018-06-28 14:20 ` [PATCH 3/6] net: don't detour through struct to find the poll head Christoph Hellwig
2018-06-28 14:20   ` Christoph Hellwig
2018-06-28 14:20 ` [PATCH 4/6] net: remove busy polling from sock_get_poll_head Christoph Hellwig
2018-06-28 14:20   ` Christoph Hellwig
2018-06-28 14:20 ` [PATCH 5/6] net: remove sock_poll_busy_loop Christoph Hellwig
2018-06-28 14:20   ` Christoph Hellwig
2018-06-28 14:20 ` [PATCH 6/6] fs: replace f_ops->get_poll_head with a static ->f_poll_head pointer Christoph Hellwig
2018-06-28 14:20   ` Christoph Hellwig
2018-06-28 16:40   ` Linus Torvalds
2018-06-28 16:40     ` Linus Torvalds
2018-06-28 18:17     ` Al Viro
2018-06-28 18:17       ` Al Viro
2018-06-28 19:31       ` Linus Torvalds
2018-06-28 19:31         ` Linus Torvalds
2018-06-28 20:28         ` Al Viro
2018-06-28 20:28           ` Al Viro
2018-06-28 20:37           ` Al Viro
2018-06-28 20:37             ` Al Viro
2018-06-28 21:16             ` Linus Torvalds
2018-06-28 21:16               ` Linus Torvalds
2018-06-28 21:11           ` Linus Torvalds
2018-06-28 21:11             ` Linus Torvalds
2018-06-28 21:30             ` Al Viro
2018-06-28 21:30               ` Al Viro
2018-06-28 21:39               ` Linus Torvalds
2018-06-28 21:39                 ` Linus Torvalds
2018-06-28 22:20               ` Al Viro
2018-06-28 22:20                 ` Al Viro
2018-06-28 22:35                 ` Linus Torvalds
2018-06-28 22:35                   ` Linus Torvalds
2018-06-28 22:49                   ` Al Viro
2018-06-28 22:49                     ` Al Viro
2018-06-28 22:55                     ` Linus Torvalds
2018-06-28 22:55                       ` Linus Torvalds
2018-06-28 23:37                       ` Al Viro
2018-06-28 23:37                         ` Al Viro
2018-06-29  0:13                         ` Linus Torvalds [this message]
2018-06-29  0:13                           ` Linus Torvalds
2018-06-29 13:29               ` Christoph Hellwig
2018-06-29 13:29                 ` Christoph Hellwig
2018-06-29 13:40                 ` Linus Torvalds
2018-06-29 13:40                   ` Linus Torvalds
2018-06-29 13:28             ` Christoph Hellwig
2018-06-29 13:28               ` Christoph Hellwig

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='CA+55aFxeZATKBRBsws=94BP8ZxsCv9HE9MBmwe-reuTVZFq=WQ@mail.gmail.com' \
    --to=torvalds@linux-foundation.org \
    --cc=hch@lst.de \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=lkp@01.org \
    --cc=netdev@vger.kernel.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 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.