From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DC32423C4FF; Fri, 26 Jun 2026 09:34:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782466488; cv=none; b=e5s2eWvm+y6fF89L35LYfd1OJhja+JE091vtoZlQr87lOAEuQ1RewVi7JvfGumjrGjmPUupB6b656RGmqnpyCLinkOujO0XMbtq621uOS91D13yoaM6pwAe91ANtCBGL+am347swsXTZk2v554ma2o0WLTlpM2wcZzCQna6GI58= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782466488; c=relaxed/simple; bh=krZHw5SfK5w0H+RYzPwaMiAXDM+GY4v8+acbYdZWd8I=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=jsBe4alxRgbOZvZlsH4jBEFbEPJjqnPUimnfDlzbxeX3MXfN5p9ICkxx1SO3HwJJ1WLt56RSISuyQrlmrCwN+bGAW6M/i468IgEUQUtB783iLttFsSu5GPRLPGoEf/bHZ0+Y/ZfK2vJpcORbC4S/82R0oOukGFaM9BGW070c7Zg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=pass smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=rgAv5xJA; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="rgAv5xJA" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Transfer-Encoding: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Sender:Reply-To:Content-ID:Content-Description; bh=8x0Ht+AgzN/+Z1jXgD/X2IuKYOvaDDgoJ0Syoi7rtDw=; b=rgAv5xJAYJFln/8iTUeNrRpcuN DnMeOkpUoF89lsz8VO3DcHNB9WBYKjcMMkZR9LEmjeA7LruYHb7KOAm+Mlnpc/sX1gz0tLIT7zBQB KqwpVejwTLL+tvrr840JT8xe/D4z303MfISvxdyQzKHpRhFCBLaSD5Jcwc54pvFqGocqm5T1Spmk4 3LFlzQtGmEe9S64FmMGozmGHSg9YMEUO45abhjg6SGnJKnipM0XIIdVIH30zHYGxKdwJN00+M/cRg F19BR0RdPiW7qzBfdLoYQZaqv3zpciuq9B9WpYy4vmfeWA9hb30mFDW98P8YLN1grHr52mfTuViEZ bEPGVIAQ==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.99.1 #2 (Red Hat Linux)) id 1wd2ww-0000000Ba7Y-1lw1; Fri, 26 Jun 2026 09:34:14 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 65455300BDE; Fri, 26 Jun 2026 11:34:14 +0200 (CEST) Date: Fri, 26 Jun 2026 11:34:14 +0200 From: Peter Zijlstra To: Shrikanth Hegde Cc: linux-kernel@vger.kernel.org, mingo@kernel.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, yury.norov@gmail.com, kprateek.nayak@amd.com, iii@linux.ibm.com, corbet@lwn.net, tglx@kernel.org, gregkh@linuxfoundation.org, pbonzini@redhat.com, seanjc@google.com, vschneid@redhat.com, huschle@linux.ibm.com, rostedt@goodmis.org, dietmar.eggemann@arm.com, maddy@linux.ibm.com, srikar@linux.ibm.com, hdanton@sina.com, chleroy@kernel.org, vineeth@bitbyteword.org, frederic@kernel.org, arighi@nvidia.com, pauld@redhat.com, christian.loehle@arm.com, tj@kernel.org, tommaso.cucinotta@gmail.com, maz@kernel.org, rafael@kernel.org, rdunlap@infradead.org, kernellwp@gmail.com, linux-doc@vger.kernel.org Subject: Re: [PATCH v5 04/24] cpumask: Introduce cpu_preferred_mask Message-ID: <20260626093414.GM1181229@noisy.programming.kicks-ass.net> References: <20260625124648.802832-1-sshegde@linux.ibm.com> <20260625124648.802832-5-sshegde@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260625124648.802832-5-sshegde@linux.ibm.com> On Thu, Jun 25, 2026 at 06:16:28PM +0530, Shrikanth Hegde wrote: > This patch does > - Declare and Define cpu_preferred_mask. > - Get/Set helpers for it. There is a blub in submitting-patches.rst about how 'this patch' is basically a red-flag for a changelog. The changelog is per-definition pertaining to 'this patch', therefore stating this is a tautology. Further, it is often fairly clear what the patch does, but less clear as to why. So the suggestion is to phrase this like: Provide cpu_preferred_mask infrastructure (definitions, declarations and helper methods) to facilitate .... > Values are set/clear by the scheduler by detecting the steal time values. > > A CPU is set to preferred when it becomes active. Later it may be > marked as non-preferred depending on steal time values with > steal monitor being enabled. > > Always maintain design construct of preferred is subset of active. > i.e. preferred ⊆ active ⊆ online ⊆ present ⊆ possible > > Signed-off-by: Shrikanth Hegde