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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org,
	=?utf-8?B?QW5kcsOp?= Almeida <andrealmeid@igalia.com>,
	Darren Hart <dvhart@infradead.org>,
	Davidlohr Bueso <dave@stgolabs.net>, Ingo Molnar <mingo@redhat.com>,
	Juri Lelli <juri.lelli@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Valentin Schneider <vschneid@redhat.com>,
	Waiman Long <longman@redhat.com>
Subject: Re: [PATCH v8 04/15] futex: Allow automatic allocation of process
 wide futex hash.
Message-ID: <20250203155417.UxZ0aBrC@linutronix.de>
References: <20250203135935.440018-1-bigeasy@linutronix.de>
 <20250203135935.440018-5-bigeasy@linutronix.de>
 <20250203143602.GK7145@noisy.programming.kicks-ass.net>
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In-Reply-To: <20250203143602.GK7145@noisy.programming.kicks-ass.net>

On 2025-02-03 15:36:02 [+0100], Peter Zijlstra wrote:
> On Mon, Feb 03, 2025 at 02:59:24PM +0100, Sebastian Andrzej Siewior wrote:
> > Allocate a default futex hash if a task forks its first thread.
> 
> This makes it so that private futexes are *always* on the mm local hash;
> there is no way to disable this.
> 
> This seems somewhat extreme.

That was the plan. But disabling it before creating threads is doable if
needed.

Sebastian