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Mon, 2 Mar 2026 23:32:41 +0000 Message-ID: <486d59a6-4c8b-49e3-a1d1-673c9224bce2@intel.com> Date: Mon, 2 Mar 2026 15:32:39 -0800 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4] fs/resctrl: Add CONFIG_RESCTRL_ASSIGN_FIXED Kconfig entry To: Ben Horgan , Borislav Petkov CC: , , , , References: <20260204161952.685921-1-ben.horgan@arm.com> <20260301104918.GCaaQZrlomC0Bw-wM3@fat_crate.local> <9b2c1318-3f59-4d21-8b15-922bdac8114c@arm.com> Content-Language: en-US From: Reinette Chatre In-Reply-To: <9b2c1318-3f59-4d21-8b15-922bdac8114c@arm.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: MW4PR02CA0028.namprd02.prod.outlook.com (2603:10b6:303:16d::7) To SJ2PR11MB7573.namprd11.prod.outlook.com (2603:10b6:a03:4d2::10) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SJ2PR11MB7573:EE_|DM6PR11MB4547:EE_ X-MS-Office365-Filtering-Correlation-Id: 582be854-3d46-4606-ceec-08de78b3ff5a X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|366016|1800799024|7053199007; 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It is not obvious to me why the one in resctrl_mbm_assign_mode_show() is required if a new arch helper could suffice in other parts > > The Kconfig was effectively added in: > > commit 3b497c3f4f04 ("fs/resctrl: Introduce the interface to display monitoring modes") > > and I was just filling in the missing piece. Most arch specific things in resctrl seem > to be dealt with using resctrl_arch_* hooks. Would it be preferable to create a new one of these? It looks to me as though this patch fits in with the other series you posted at https://lore.kernel.org/lkml/20260225201905.3568624-1-ben.horgan@arm.com/ When looking at this patch together with the other series there may indeed be an arch helper that can replace CONFIG_RESCTRL_ASSIGN_FIXED but as I mentioned in that series the MPAM capabilities and strategies for resctrl to support them are not clear to me at this time. > It could be resctrl_arch_mbm_cntr_assign_fixed() although we seem to be getting too many > of these too. Perhaps we could extend the meaning of another hook, resctrl_arch_mbm_assign_set() could Could you please elaborate which category of helper is getting to be too many? We can surely explore improvements. > return -EOPNOTSUPP to indicate to resctrl that the counter assignment mode is not configurable. > Reinette