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Date: Wed, 22 Oct 2025 08:38:10 -1000
From: Tejun Heo <tj@kernel.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: David Vernet <void@manifault.com>, Andrea Righi <arighi@nvidia.com>,
	Changwoo Min <changwoo@igalia.com>, linux-kernel@vger.kernel.org,
	sched-ext@lists.linux.dev, bpf@vger.kernel.org,
	Wen-Fang Liu <liuwenfang@honor.com>
Subject: Re: sched_ext: Fix SCX_KICK_WAIT to work reliably
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References: <20251021210354.89570-1-tj@kernel.org>
 <20251021210354.89570-3-tj@kernel.org>
 <20251022080346.GH4067720@noisy.programming.kicks-ass.net>
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On Wed, Oct 22, 2025 at 10:03:46AM +0200, Peter Zijlstra wrote:
> >  			while (smp_load_acquire(wait_pnt_seq) == pseqs[cpu])
> >  				cpu_relax();
> 
> You could consider using:
> 
> 			smp_cond_load_acquire(wait_pnt_seq, VAL !+ pseqs[cpu]);
> 
> that's the fancy way of doing a spin wait and allows architectures to
> optimize (mostly arm64 at this point).

Will do. Thanks.

-- 
tejun