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McKenney" , Frederic Weisbecker , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Uladzislau Rezki , Mathieu Desnoyers , Lai Jiangshan , Zqiang , Tejun Heo , Andrew Morton , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , Zi Yan , Anna-Maria Behnsen , Ingo Molnar , Shuah Khan , linux-kernel@vger.kernel.org, rcu@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org Subject: Re: [PATCH 01/15] sched/isolation: Support dynamic allocation for housekeeping masks Message-ID: <20260325135707.GZ3738786@noisy.programming.kicks-ass.net> References: <20260325-dhei-v12-final-v1-0-919cca23cadf@gmail.com> <20260325-dhei-v12-final-v1-1-919cca23cadf@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260325-dhei-v12-final-v1-1-919cca23cadf@gmail.com> X-Rspamd-Queue-Id: 4BA67140004 X-Stat-Signature: t9z5qfypjx19d1bopfmmfnh8o6chq8mk X-Rspam-User: X-Rspamd-Server: rspam02 X-HE-Tag: 1774447037-895860 X-HE-Meta: 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 29bR82pE 4QmLcicybFdIEF9wz/5w2JBxHIlAAYHkC+qIZbWD1em+gXsGslKFAwkGq948LIBD2aTvaO03oUrgwgHCPqT/B7tmhMzCr59jqk8Ht1WrOxZSNcj46F1nmZ6eycVPTKI4ijIPMWvrAF5bT7G0dv1oWCldC5JgQaAjzFg9g0ARHeHTKzuYMuAVWer3IBAaAzPw9k1iEuhuNXgMDbQMiU0nkHU6E2xRBq8Xt+CE6+6F55s9OUGR2EZK8BMCW51lFasnjGvpDBFVOlKmBtGdK1kPtqResOI39OOyxPTKfkWacNzRN83ypi4EIauhowg== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Mar 25, 2026 at 05:09:32PM +0800, Qiliang Yuan wrote: > The existing housekeeping infrastructure uses a single static cpumask > for all isolation types. This prevents independent runtime > reconfiguration of different services (like RCU vs. timers). I think I asked this a while ago; why do we have more than one mask? What is the actual purpose of being able to separate RCU from Timers?