linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: "Ulrich Drepper" <drepper@gmail.com>
To: Eric Dumazet <dada1@cosmosbay.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>,
	Nick Piggin <nickpiggin@yahoo.com.au>,
	Ingo Molnar <mingo@elte.hu>, Thomas Gleixner <tglx@linutronix.de>,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH 0/4] futex: get_user_pages_fast() for shared futexes
Date: Tue, 30 Sep 2008 20:13:44 -0700	[thread overview]
Message-ID: <a36005b50809302013w54db0985o635bcbef05a9e8f3@mail.gmail.com> (raw)
In-Reply-To: <48E205BE.8030908@cosmosbay.com>

On Tue, Sep 30, 2008 at 3:55 AM, Eric Dumazet <dada1@cosmosbay.com> wrote:
> I am not sure how it could be converted to private futexes, since
> old binaries (static glibc) will use FUTEX_WAKE like calls.

We considered this back when but any effort seems too much.  We'd
either need a clone flag (a scarce resource) or replace the set_tid
_address syscall.  Given that the futex is woken once per thread
lifetime it shouldn't be an issue.  If the semaphore shows up even
after this patch feel free to introduce a new set_tid_address syscall.

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  parent reply	other threads:[~2008-10-01  3:13 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-09-26 17:32 Peter Zijlstra
2008-09-26 17:32 ` [PATCH 1/4] futex: rely on get_user_pages() " Peter Zijlstra
2008-09-26 17:32 ` [PATCH 2/4] futex: reduce mmap_sem usage Peter Zijlstra
2008-09-26 17:32 ` [PATCH 3/4] futex: use fast_gup() Peter Zijlstra
2008-09-26 17:32 ` [PATCH 4/4] futex: cleanup fshared Peter Zijlstra
2008-09-27 16:17 ` [PATCH 0/4] futex: get_user_pages_fast() for shared futexes Ingo Molnar
2008-09-30  7:21   ` Nick Piggin
2008-09-30  8:51     ` Peter Zijlstra
2008-09-30 10:39       ` Ingo Molnar
2008-09-30 10:42       ` Nick Piggin
2008-09-30 10:55       ` Eric Dumazet
2008-09-30 11:16         ` Peter Zijlstra
2008-10-01  3:13         ` Ulrich Drepper [this message]
2008-09-30 10:39     ` Ingo Molnar

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=a36005b50809302013w54db0985o635bcbef05a9e8f3@mail.gmail.com \
    --to=drepper@gmail.com \
    --cc=a.p.zijlstra@chello.nl \
    --cc=dada1@cosmosbay.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mingo@elte.hu \
    --cc=nickpiggin@yahoo.com.au \
    --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