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Date: Wed, 25 Mar 2026 15:04:32 +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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	Joel Fernandes <joelagnelf@nvidia.com>,
	Josh Triplett <josh@joshtriplett.org>,
	Boqun Feng <boqun.feng@gmail.com>,
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	Michal Hocko <mhocko@suse.com>,
	Brendan Jackman <jackmanb@google.com>,
	Johannes Weiner <hannes@cmpxchg.org>, Zi Yan <ziy@nvidia.com>,
	Anna-Maria Behnsen <anna-maria@linutronix.de>,
	Ingo Molnar <mingo@kernel.org>, Shuah Khan <shuah@kernel.org>,
	linux-kernel@vger.kernel.org, rcu@vger.kernel.org,
	linux-mm@kvack.org, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH 13/15] sched/isolation: Implement sysfs interface for
 dynamic housekeeping
Message-ID: <20260325140432.GE3738786@noisy.programming.kicks-ass.net>
References: <20260325-dhei-v12-final-v1-0-919cca23cadf@gmail.com>
 <20260325-dhei-v12-final-v1-13-919cca23cadf@gmail.com>
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In-Reply-To: <20260325-dhei-v12-final-v1-13-919cca23cadf@gmail.com>

On Wed, Mar 25, 2026 at 05:09:44PM +0800, Qiliang Yuan wrote:
> Subsystem housekeeping masks are currently static and can only be set
> via boot-time parameters (isolcpus, nohz_full, etc.). There is no
> userspace interface to reconfigure these boundaries at runtime.
> 
> Implement the DHEI sysfs interface under /sys/kernel/housekeeping.
> 

Why? What was wrong with cpusets?