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b=D6xnVSsF99C3u/uxJ+cNa2GAaC5wVSRy2cWeCsuIbMr3VbC2FiiWmJ0+AvDCiOTXSiTp5d2citQwehp1dUGyasp5IG038Gkn43xXoaUdwjPB/0PrfniXGwwuIsnAr0KzwS7V2HLedb5yn5ckYj5Rl0n+ZOINPlAw6ZQxleUO8lM= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from IA0PPF9A76BB3A6.namprd12.prod.outlook.com (2603:10b6:20f:fc04::bdc) by SA1PR12MB6703.namprd12.prod.outlook.com (2603:10b6:806:253::18) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9320.15; Tue, 11 Nov 2025 21:04:57 +0000 Received: from IA0PPF9A76BB3A6.namprd12.prod.outlook.com ([fe80::8d61:56ca:a8ea:b2eb]) by IA0PPF9A76BB3A6.namprd12.prod.outlook.com ([fe80::8d61:56ca:a8ea:b2eb%8]) with mapi id 15.20.9320.013; Tue, 11 Nov 2025 21:04:57 +0000 Message-ID: <589d5db4-68f8-4aee-9d6e-dee5b8754564@amd.com> Date: Tue, 11 Nov 2025 15:04:55 -0600 User-Agent: Mozilla Thunderbird From: Babu Moger Subject: Re: [PATCH 1/2] x86/resctrl: Add io_alloc_min_cbm_all interface for CBM reset To: Aaron Tomlin , "Luck, Tony" Cc: "Chatre, Reinette" , "Dave.Martin@arm.com" , "james.morse@arm.com" , "babu.moger@amd.com" , "tglx@linutronix.de" , "mingo@redhat.com" , "bp@alien8.de" , "dave.hansen@linux.intel.com" , "linux-kernel@vger.kernel.org" References: <20251107012401.224515-2-atomlin@atomlin.com> <2a0b270a-e398-4d88-aa10-421f2769a759@amd.com> <53iuqiul6uo7zj6sfckm2h465cjusaxvpxrtdmnbmhvbzuqiq6@7ogm3zqddzjd> <4whfbgq336xfuov4i4nwwrn35ywwlwizuvpdlstmdqzkhvwrq6@eits26xbwyz6> <937022c8-82cb-4f4c-a2a3-ceaf99580cc6@intel.com> <7e264e18-23f4-4566-86f2-f0600a243227@amd.com> Content-Language: en-US In-Reply-To: <7e264e18-23f4-4566-86f2-f0600a243227@amd.com> Content-Type: text/plain; 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This operation relies entirely on >> r->cache.min_cbm_bits. Since this value is guaranteed by the hardware >> to be >> valid, this approach is robust and will not return an error (e.g., >> -EINVAL) >> to userspace. >> >> > > Here’s my understanding of the discussion from this thread: > > > We plan to support the following operation: > >    #echo "*=value" > /sys/fs/resctrl/info/L3/io_alloc_cbm > Looks like we are going with the above approach where "*" represents all the domain. Couple of things to consider. a. Send a separate patch to add this feature after [1] is merged. b. Add this change as part of [1] series in patch 9. The series is mostly ready for merge. I can add the changes. Only concern is, it will might delay the series merge little bit.  My expectation is to have this series ready for next merge window. [1] https://lore.kernel.org/lkml/cover.1761844489.git.babu.moger@amd.com/ Any thoughts? Thanks Babu