From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Chris Mason <clm@meta.com>,
linux-kernel@vger.kernel.org,
Thomas Gleixner <tglx@linutronix.de>
Subject: Re: futex performance regression from "futex: Allow automatic allocation of process wide futex hash"
Date: Thu, 26 Jun 2025 15:50:34 +0200 [thread overview]
Message-ID: <20250626135034.18sab4Xp@linutronix.de> (raw)
In-Reply-To: <20250626131715.GI1613200@noisy.programming.kicks-ass.net>
On 2025-06-26 15:17:15 [+0200], Peter Zijlstra wrote:
> > I'd vote for defaulting to global for one more release.
>
> Probably best to do that; means we don't have to rush crazy code :-)
If we do that, that means we need to ensure that the private hash is not
deployed while a thread is created and the prctl() function can only
work create the private hash if the application is single threaded.
Sebastian
next prev parent reply other threads:[~2025-06-26 13:50 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-06-03 19:00 futex performance regression from "futex: Allow automatic allocation of process wide futex hash" Chris Mason
2025-06-04 9:28 ` Sebastian Andrzej Siewior
2025-06-04 15:48 ` Chris Mason
2025-06-04 20:08 ` Sebastian Andrzej Siewior
2025-06-06 0:55 ` Chris Mason
2025-06-06 7:06 ` Sebastian Andrzej Siewior
2025-06-06 21:06 ` Chris Mason
2025-06-06 22:17 ` Chris Mason
2025-06-24 19:01 ` Peter Zijlstra
2025-06-26 11:01 ` Chris Mason
2025-06-26 13:17 ` Peter Zijlstra
2025-06-26 13:50 ` Sebastian Andrzej Siewior [this message]
2025-06-27 11:04 ` Peter Zijlstra
2025-06-27 12:14 ` Sebastian Andrzej Siewior
2025-06-30 14:50 ` [PATCH] futex: Temporary disable FUTEX_PRIVATE_HASH Sebastian Andrzej Siewior
2025-07-01 13:13 ` [tip: locking/urgent] " tip-bot2 for Sebastian Andrzej Siewior
2025-07-16 1:34 ` [PATCH] " kernel test robot
2025-06-26 13:48 ` futex performance regression from "futex: Allow automatic allocation of process wide futex hash" Sebastian Andrzej Siewior
2025-06-26 14:36 ` Peter Zijlstra
2025-06-27 12:24 ` Sebastian Andrzej Siewior
2025-06-27 22:48 ` Tim Chen
2025-06-28 8:23 ` Peter Zijlstra
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