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b=pkoMTLy/7MWzbmWXg9t+Hlj/s0fNN/r0bRGIh5qnEQ9vJQBS/v1ZhvhYHPtoOwiIx+FDzhu8ytM2xtpiukAPaVPTM1Es2vd1iPG7YUehew7PenFQ8MSHY/zEARPSrs25wqKGrZZneQ9TayIFqg/8zaiRvAalAUN43cPm/o2Fdng= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from SA0PR12MB4557.namprd12.prod.outlook.com (2603:10b6:806:9d::10) by MN0PR12MB6200.namprd12.prod.outlook.com (2603:10b6:208:3c3::18) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8678.23; Tue, 22 Apr 2025 17:59:34 +0000 Received: from SA0PR12MB4557.namprd12.prod.outlook.com ([fe80::d22d:666e:be69:117f]) by SA0PR12MB4557.namprd12.prod.outlook.com ([fe80::d22d:666e:be69:117f%3]) with mapi id 15.20.8655.033; Tue, 22 Apr 2025 17:59:34 +0000 Message-ID: <93da0002-a326-49f2-af5d-f89da9d3a8f6@amd.com> Date: Tue, 22 Apr 2025 12:59:31 -0500 User-Agent: Mozilla Thunderbird Subject: Re: RE: [PATCH v8 08/21] x86/resctrl: Expand the width of dom_id by replacing mon_data_bits To: "Luck, Tony" , James Morse , "x86@kernel.org" , "linux-kernel@vger.kernel.org" Cc: "Chatre, Reinette" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , H Peter Anvin , Babu Moger , "shameerali.kolothum.thodi@huawei.com" , D Scott Phillips OS , "carl@os.amperecomputing.com" , "lcherian@marvell.com" , "bobo.shaobowang@huawei.com" , "tan.shaopeng@fujitsu.com" , "baolin.wang@linux.alibaba.com" , Jamie Iles , Xin Hao , "peternewman@google.com" , "dfustini@baylibre.com" , "amitsinght@marvell.com" , David Hildenbrand , Rex Nie , Dave Martin , "Ko, Koba" , Shanker Donthineni , "fenghuay@nvidia.com" References: <20250411164229.23413-1-james.morse@arm.com> <20250411164229.23413-9-james.morse@arm.com> <70403b1c-d81f-4c5f-936e-f3cf3308822f@amd.com> Content-Language: en-US From: "Moger, Babu" In-Reply-To: Content-Type: text/plain; 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Expand dom_id. >> >> 2. Pack all necessary data (dom_id, event_id, resid) into the >> of->kn->priv pointer when creating event files in the mon_data >> directory for each domain. > > This step includes searching the list of previously created priv structures > to find a matching one that can be shared. This happens all the time > because the same set of values is re-used over and over. Essentially > we only allocate anything while creating the mon_data directory in the > root directory of resctrl. James' original implementation made use of > this by special case allocation for the default group, and then doing > kernfs lookups while creating new groups to find the matching one > and linking to the same ->priv pointer. > oh ok. I went back and looked at the history. https://lore.kernel.org/all/20250228195913.24895-38-james.morse@arm.com/ So you are saying, kernfs lookup method is much more complex. So, having the global list is easy to traverse and efficient? Thanks Babu