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Fri, 5 Jun 2026 05:40:37 +0000 Date: Fri, 5 Jun 2026 13:40:25 +0800 From: Chao Gao To: Kiryl Shutsemau CC: "Edgecombe, Rick P" , "kvm@vger.kernel.org" , "linux-coco@lists.linux.dev" , "Huang, Kai" , "Hansen, Dave" , "Zhao, Yan Y" , "seanjc@google.com" , "mingo@redhat.com" , "linux-kernel@vger.kernel.org" , "pbonzini@redhat.com" , "nik.borisov@suse.com" , "linux-doc@vger.kernel.org" , "hpa@zytor.com" , "tglx@kernel.org" , "Annapurve, Vishal" , "bp@alien8.de" , "kirill.shutemov@linux.intel.com" , "x86@kernel.org" Subject: Re: [PATCH v6 06/11] x86/virt/tdx: Optimize tdx_pamt_get/put() Message-ID: References: <20260526023515.288829-1-rick.p.edgecombe@intel.com> <20260526023515.288829-7-rick.p.edgecombe@intel.com> Content-Type: text/plain; charset="utf-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-ClientProxiedBy: SI3PR02CA0011.apcprd02.prod.outlook.com (2603:1096:4:295::18) To BN7PR11MB2836.namprd11.prod.outlook.com (2603:10b6:406:ad::26) Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BN7PR11MB2836:EE_|CY8PR11MB7290:EE_ X-MS-Office365-Filtering-Correlation-Id: 32ede19f-a746-43de-3859-08dec2c4f8c3 X-LD-Processed: 46c98d88-e344-4ed4-8496-4ed7712e255d,ExtAddr X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|376014|7416014|1800799024|22082099003|18002099003|56012099006|11063799006|4143699003; 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It would reduce code churn if the >> > previous patch used that form directly. >> >> Yea, it's a good point. I actually debated doing it, but decided not to because >> the scoped version is cleaner for the non-optimized version. But for >> reviewability, never doing the scoped version is probably better. > >I don't see a reason why we can't keep the scoped_guard() on get side. One additional reason to drop scoped_guard() is that it mixes cleanup helpers with goto, which is discouraged. See [*] :Lastly, given that the benefit of cleanup helpers is removal of “goto”, and :that the “goto” statement can jump between scopes, the expectation is that :usage of “goto” and cleanup helpers is never mixed in the same function. Removing scoped_guard() here also reduces indentation. *: https://www.kernel.org/doc/html/v7.1-rc6/core-api/cleanup.html > >On put side, we cannot get atomic_get_and_lock() semantics without >dropping the scoped_guard(). > >Maybe we should keep it for get? > >-- > Kiryl Shutsemau / Kirill A. Shutemov