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Date: Wed, 25 Mar 2026 14:59:04 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Qiliang Yuan <realwujing@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>, Juri Lelli <juri.lelli@redhat.com>,
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	linux-kernel@vger.kernel.org, rcu@vger.kernel.org,
	linux-mm@kvack.org, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH 03/15] sched/isolation: Separate housekeeping types in
 enum hk_type
Message-ID: <20260325135904.GB3738786@noisy.programming.kicks-ass.net>
References: <20260325-dhei-v12-final-v1-0-919cca23cadf@gmail.com>
 <20260325-dhei-v12-final-v1-3-919cca23cadf@gmail.com>
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In-Reply-To: <20260325-dhei-v12-final-v1-3-919cca23cadf@gmail.com>

On Wed, Mar 25, 2026 at 05:09:34PM +0800, Qiliang Yuan wrote:
> Most kernel noise types (TICK, TIMER, RCU, etc.) are currently
> aliased to a single HK_TYPE_KERNEL_NOISE enum value. This prevents
> fine-grained runtime isolation control as all masks are forced to be
> identical.
> 
> Un-alias service-specific housekeeping types in enum hk_type.
> 
> This separation provides the necessary granularity for DHEI subsystems
> to subscribe to and maintain independent affinity masks.

What the hell for?