From: Pavel Begunkov <asml.silence@gmail.com>
To: Jens Axboe <axboe@kernel.dk>, io-uring@vger.kernel.org
Cc: Andres Freund <andres@anarazel.de>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Darren Hart <dvhart@infradead.org>,
Davidlohr Bueso <dave@stgolabs.net>,
linux-kernel@vger.kernel.org
Subject: Re: [RFC 4/4] io_uring: implement futex wait
Date: Tue, 1 Jun 2021 16:58:22 +0100 [thread overview]
Message-ID: <409a624c-de75-0ee5-b65f-ee09fff34809@gmail.com> (raw)
In-Reply-To: <bd824ec8-48af-b554-67a1-7ce20fcf608c@kernel.dk>
On 6/1/21 4:45 PM, Jens Axboe wrote:
> On 6/1/21 8:58 AM, Pavel Begunkov wrote:
>> Add futex wait requests, those always go through io-wq for simplicity.
>
> Not a huge fan of that, I think this should tap into the waitqueue
> instead and just rely on the wakeup callback to trigger the event. That
> would be a lot more efficient than punting to io-wq, both in terms of
> latency on trigger, but also for efficiency if the app is waiting on a
> lot of futexes.
Yes, that would be preferable, but looks futexes don't use
waitqueues but some manual enqueuing into a plist_node, see
futex_wait_queue_me() or mark_wake_futex().
Did I miss it somewhere?
--
Pavel Begunkov
next prev parent reply other threads:[~2021-06-01 15:58 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-01 14:58 [RFC 0/4] futex request support Pavel Begunkov
2021-06-01 14:58 ` [RFC 1/4] futex: add op wake for a single key Pavel Begunkov
2021-06-01 14:58 ` [RFC 2/4] io_uring: frame out futex op Pavel Begunkov
2021-06-01 14:58 ` [RFC 3/4] io_uring: support futex wake requests Pavel Begunkov
2021-06-01 14:58 ` [RFC 4/4] io_uring: implement futex wait Pavel Begunkov
2021-06-01 15:45 ` Jens Axboe
2021-06-01 15:58 ` Pavel Begunkov [this message]
2021-06-01 16:01 ` Jens Axboe
2021-06-01 16:29 ` Pavel Begunkov
2021-06-01 21:53 ` Thomas Gleixner
2021-06-03 10:31 ` Pavel Begunkov
2021-06-04 9:19 ` Thomas Gleixner
2021-06-04 11:58 ` Pavel Begunkov
2021-06-05 2:09 ` Thomas Gleixner
2021-06-07 12:14 ` Pavel Begunkov
2021-06-03 19:03 ` Andres Freund
2021-06-03 21:10 ` Peter Zijlstra
2021-06-03 21:21 ` Andres Freund
2021-06-05 0:43 ` Thomas Gleixner
2021-06-07 11:31 ` Pavel Begunkov
2021-06-07 11:48 ` Peter Zijlstra
2021-06-03 18:59 ` [RFC 0/4] futex request support Andres Freund
2021-06-04 15:26 ` Pavel Begunkov
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=409a624c-de75-0ee5-b65f-ee09fff34809@gmail.com \
--to=asml.silence@gmail.com \
--cc=andres@anarazel.de \
--cc=axboe@kernel.dk \
--cc=dave@stgolabs.net \
--cc=dvhart@infradead.org \
--cc=io-uring@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
/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).