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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: "André Almeida" <andrealmeid@igalia.com>
Cc: Juri Lelli <juri.lelli@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@redhat.com>,
	Darren Hart <dvhart@infradead.org>,
	Davidlohr Bueso <dave@stgolabs.net>,
	LKML <linux-kernel@vger.kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	linux-rt-users <linux-rt-users@vger.kernel.org>,
	Valentin Schneider <vschneid@redhat.com>,
	Waiman Long <longman@redhat.com>
Subject: Re: Futex hash_bucket lock can break isolation and cause priority inversion on RT
Date: Tue, 8 Oct 2024 20:09:11 +0200	[thread overview]
Message-ID: <20241008180911.JiqZxSLg@linutronix.de> (raw)
In-Reply-To: <46c259c2-5503-4a63-94ae-96660e5ce0eb@igalia.com>

On 2024-10-08 12:59:24 [-0300], André Almeida wrote:
> 
> So if every process has it owns hb-lock, every process has their own bucket?
> It would act just like a linked list then?

If you have one hb-lock, yes. But you could have 4 or 8 slots. A slot
has 64 bytes due to alignment. As-is the 8 slots would occupy 512 bytes
of memory.

Sebastian

  reply	other threads:[~2024-10-08 18:09 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-10-08 15:22 Futex hash_bucket lock can break isolation and cause priority inversion on RT Juri Lelli
2024-10-08 15:38 ` André Almeida
2024-10-08 15:51   ` Sebastian Andrzej Siewior
2024-10-08 15:59     ` André Almeida
2024-10-08 18:09       ` Sebastian Andrzej Siewior [this message]
2024-10-09  8:36       ` Juri Lelli
2024-10-24 22:36         ` Thomas Gleixner
2024-10-08 17:38 ` Peter Zijlstra
2024-10-08 19:44   ` Waiman Long
2024-10-09  7:22     ` Peter Zijlstra
2024-10-09  8:26   ` Juri Lelli
2024-10-08 18:30 ` Waiman Long
2024-10-09  8:28   ` Juri Lelli

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