From: "Jₑₙₛ Gustedt" <jens.gustedt@inria.fr>
To: Carlos O'Donell <carlos@redhat.com>
Cc: Alejandro Colomar <alx@kernel.org>, linux-man@vger.kernel.org
Subject: Re: bug in futex.2, FUTEX_CMP_REQUEUE
Date: Tue, 27 May 2025 14:21:18 +0200 [thread overview]
Message-ID: <20250527142118.05d15dd9@inria.fr> (raw)
In-Reply-To: <8b77ea67-2662-411a-83c8-e0e23755244f@redhat.com>
Hello Carlos,
On Tue, 27 May 2025 07:30:09 -0400, Carlos O'Donell wrote:
> > This has several issues, the most severe beeing the word
> > `FUTEX_WAIT`.
> >
> > - How can an operation that only does wakes, ever be equivalent to a
> > wait?
>
> My opinion is that the text is correct.
>
> The operation can WAKE tasks.
>
> The operation can also cause tasks to WAIT in a *different* queue.
No, it can make *other* threads wait in a different queue. The
`FUTEX_WAIT` call is to put the current thread on wait. So calling
this equivalent is really far fetched.
Thanks
Jₑₙₛ
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next prev parent reply other threads:[~2025-05-27 12:21 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-05-27 9:53 bug in futex.2, FUTEX_CMP_REQUEUE Jₑₙₛ Gustedt
2025-05-27 11:30 ` Carlos O'Donell
2025-05-27 12:21 ` Jₑₙₛ Gustedt [this message]
2025-05-27 12:28 ` Carlos O'Donell
2025-05-27 12:23 ` Alejandro Colomar
2025-05-27 12:35 ` Carlos O'Donell
2025-05-27 12:01 ` Alejandro Colomar
2025-05-27 12:12 ` Carlos O'Donell
2025-05-27 12:28 ` Jₑₙₛ Gustedt
2025-05-27 12:37 ` Carlos O'Donell
2025-05-27 12:51 ` Alejandro Colomar
2025-05-27 12:54 ` Carlos O'Donell
2025-05-27 12:28 ` Alejandro Colomar
2025-05-27 12:42 ` Carlos O'Donell
2025-05-27 12:57 ` Alejandro Colomar
2025-05-27 12:59 ` Alejandro Colomar
2025-05-27 13:07 ` Jₑₙₛ Gustedt
2025-05-29 23:35 ` Alejandro Colomar
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