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Miller" , Jakub Kicinski , Paolo Abeni , Simon Horman , netdev@vger.kernel.org, Nikolay Aleksandrov , eric.dumazet@gmail.com Subject: Re: [PATCH net-next 06/11] bridge: provide lockless access to p->designated_cost Message-ID: <20260524124820.GF74116@shredder> References: <20260521131916.3627204-1-edumazet@google.com> <20260521131916.3627204-7-edumazet@google.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260521131916.3627204-7-edumazet@google.com> X-ClientProxiedBy: FR0P281CA0134.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:97::18) To SA3PR12MB7901.namprd12.prod.outlook.com (2603:10b6:806:306::12) Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SA3PR12MB7901:EE_|SA1PR12MB7269:EE_ X-MS-Office365-Filtering-Correlation-Id: 014ed7b2-38dc-405a-241e-08deb992c203 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|376014|18002099003|22082099003|56012099003|11063799006|4143699003; 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?iyeELtn5dqsrksPDZ8FlVr8fhYARc1cjzlWdjN5RDS0FZtChqeE3qMY14/1S?= =?us-ascii?Q?GU7G/XbnSKlxQo6/+UmKDllLQFza09ZhuyzH6Rc6DiTFjbIGv/EJeqQRIl7s?= =?us-ascii?Q?jX1KmtsPevft5cn+e4oYPBPffaJUjovhdkCFdKvAeADEboOsftwNzYrzG07F?= =?us-ascii?Q?MjZ5QQkVuoXi1AXo85OlkPB0qIlEgZe2J/d7rxbeqC4MtnUZiDoDRKgXmP8o?= =?us-ascii?Q?IwOqq98IgwI9pudfK7gvEd+h3AUhtXePg3imR3UvMOupHQ2wlgvQK5eb/L/c?= =?us-ascii?Q?4uhqv0IRikwiowIDzyGMhR7/J9nxra6vH0LuMrO+2FBx2Z7+ycPC9t3+9Kdl?= =?us-ascii?Q?RjgfsweIp3X4etZVpcwugq+PoTBoMObIiE5as7zdxQ0JlPt8I+o4Wsxy/gcd?= =?us-ascii?Q?BZu4cgbzAHJzaF4V9EQIWgGol7gEePTSrn/8YuztlSNZ22pGEJeKXf7QmvCk?= =?us-ascii?Q?wv+HL7jubT6WjhFuU+0yTOGzPjmhlV6EBnLmpata9SHbGH+uiAZiUtMYhmVR?= =?us-ascii?Q?dfb5h/fb1c9hwne04Uz/hoeJqyjek8NevQjt2uh4WSVH2zt6b5Ff8ykMtZ0a?= =?us-ascii?Q?N4rBw6oBZjSirj400kOEvmADSTEQGvU6ElsAsDl8yphYty7rjaQBpKem0ZLc?= =?us-ascii?Q?i9qjf+fs9oNXSAt1iYVYoz6zyZBlGiNUEz6S9Mf31jHZEWXd+Dkkzc/9VJxf?= =?us-ascii?Q?H7uvAmJQw4Q64usdmpJVxJ9U7SZbh/piELhNtRBolll2wpjt39zgKVr4CmTH?= =?us-ascii?Q?JIqHs3XPXCKOLINtJ04kXvQDnR8g2jDGH7ILNP7IJMZjfOwpTOw+mH6HuIz5?= =?us-ascii?Q?OdNoX5njwOHe+Gt7UL206J8rEd4myoEaAaEbUi58UNq/o3uID2gP/7nCLnwY?= =?us-ascii?Q?OGhmTrsTsOcDRuc30T69FKx6xC1Du2F46yQ7dfZnCwh/FLjpR6ndizGfk+D1?= =?us-ascii?Q?TXrUr5yKOl5l1soR98Fy4MqATMsA96/16V+ak/K7+kyk3tv9joeQwNFcfIeg?= =?us-ascii?Q?e3LWPfTH8yRWXGurE2PiCo6n//ZrUs4lLTvnsfbi5XiwD5NlhvzDo6sD/B3w?= =?us-ascii?Q?+WPwNCyh0FP/4AhNhMxrgpiKYDS0J3rz4lf+mq0jG1UT8eqwmvQU1v/i5za2?= =?us-ascii?Q?HVaqOsmf4RMvp3f0+qvzO1DZyxveWM9cByYBq9/LaEmv5keNZYNC1jJmNYOk?= =?us-ascii?Q?IxZK7266HO2QqgrEsNcomZbN+kGUhuMJnDTzbCmd+a/MgCy/WUx1bX2ktEFO?= =?us-ascii?Q?96O5o3aaTTTBbWl4PM0K64qPwQUcnd5ctj3dmzv1g1Szqmr6qiv8mwokH6eB?= =?us-ascii?Q?qtUSzUS0nkrS6snMKWMh7HB7tY1mr0mmlaQLlfTpqO3DGS0+xSpUJp/Gs3BT?= =?us-ascii?Q?jNVKiUi6Uo6EpvFAj9ZP9n3KYqdmqYKR5WPxEY43xJkYPfAE8yVtsEcqRKh5?= =?us-ascii?Q?yFg2VzSanWNunBO9IRCXI5fDGtJS5hqVju6nisJHmFuaVAD9FAS3kLKBHUtw?= =?us-ascii?Q?yb7kbhSKZH6f9mC0zeKBfj9vp+jWtQkoOVaJm2rdyMezdTXw2pHXvNTVQq45?= =?us-ascii?Q?8xX/i9pJmkl/AccHJTwwWBP+d9Ibg2rQimqIA0IO9N6HORUNKzigqnLy2zwf?= =?us-ascii?Q?PS/d3iDRm+SJG+rEG1u6bTv1tm5iwF3D+PJKqguhhPmlPnC6p/Vff+UXKZA2?= =?us-ascii?Q?vCsGCoXFsnIogTy4dDRDFomwcagV8SD2EBZYUD1wWi5iYqkv?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 014ed7b2-38dc-405a-241e-08deb992c203 X-MS-Exchange-CrossTenant-AuthSource: SA3PR12MB7901.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 May 2026 12:48:30.5909 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: FKnXRWPLiPB8SeH+XuW3D3sVjCDNhuspcIbfVslEsd+BsXtO1PlEIk2CRWPueSnoq6EiNcsrl3b2FBLxRPGctg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB7269 On Thu, May 21, 2026 at 01:19:11PM +0000, Eric Dumazet wrote: > @@ -299,9 +299,10 @@ static int br_should_become_designated_port(const struct net_bridge_port *p) > if (memcmp(&p->designated_root, &br->designated_root, 8)) > return 1; > > - if (br->root_path_cost < p->designated_cost) > + t = br->root_path_cost - READ_ONCE(p->designated_cost); > + if (t < 0) > return 1; > - else if (br->root_path_cost > p->designated_cost) > + else if (t > 0) > return 0; Same as previous patch. > > t = memcmp(&br->bridge_id, &p->designated_bridge, 8); > @@ -341,9 +342,10 @@ static int br_supersedes_port_info(const struct net_bridge_port *p, > else if (t > 0) > return 0; > > - if (bpdu->root_path_cost < p->designated_cost) > + t = bpdu->root_path_cost < READ_ONCE(p->designated_cost); > + if (t < 0) > return 1; > - else if (bpdu->root_path_cost > p->designated_cost) > + else if (t > 0) > return 0; Same.