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Date:   Thu, 28 Sep 2023 16:26:28 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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Subject: Re: [RFC PATCH v2 1/4] rseq: Add sched_state field to struct rseq
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On Thu, Sep 28, 2023 at 09:20:36AM -0400, Mathieu Desnoyers wrote:

> Of course things are more complicated with PI-futex, is that what you have
> in mind ?

PI futex has to go through the kernel, also, they already spin-wait on
owner.