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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?E5KLxrUsrutcEWeJ+/LsHxG/RnbJLP0j99ANxMUK4Du1LEtZmWE2UFE0m/WY?= =?us-ascii?Q?cVL4NSCYFE8tr3sh1TIC+QbI4Fk9RKvDmNPDCwckeb4L9jRxPL1/Kr+irQ14?= =?us-ascii?Q?TIUDdEX6f6tIpifNgjGT6m/VUZ47DhNxgdicqVe9FF2I0zNbSZ982WEzVpqe?= =?us-ascii?Q?w2f6LHbiGc+sgkeLJ6yOEUOPBKUX10OOkcHf0XMrtB2j8W/D3HI4zz09N4bY?= =?us-ascii?Q?1/4IvDxRFg5gkWv48ryqHj/ZWdGSWPpLsKOclDNdKJxqUtFmbA7cePAXXkdD?= =?us-ascii?Q?H4g/6TpN8hWCy2/opBvxYR/uyu+M1Oe9MAc+Ft16CX0BfzgeNxXps35VbHiz?= =?us-ascii?Q?1xerpwmAMP96NFmy3hCFG1fIk8fqX3/16RDuE29nJLRPPt932ctwMO4iA9yv?= =?us-ascii?Q?Gkk036KVD2vrA1LhG4f1Hwz1rEUEzTVxciZzGGobuYNWHPbW3GJy+Hjh/3yt?= =?us-ascii?Q?hoEEkmYUlyCUta3e8VWgsUTVX+3jKDJPqH/7Z7RRmorIeJUaIkszfjcKNLBg?= =?us-ascii?Q?l6/Wy+nrsDfoaWxLEg5syl3xnh05hIX4q0/1ZKy9ue+u6zxdJBsB2KH8HG3B?= =?us-ascii?Q?9fGq/MdHM76h6O+GTHmeX+zxYnHWa3h7JVmoi4wMhb4Eg3pLNej8+tYxP8p+?= =?us-ascii?Q?Qr9E6tKifcNN6nrgfcr6FeEDS9PPXNG/T7B/LyqAPhQ7LUCT4cuh3slCqqnF?= =?us-ascii?Q?eEWrx5BakLtZRXYm4lgpVSD9nLBsqrEDdb/0O15HxRQAv8+05HxAxgJxr/zz?= =?us-ascii?Q?Y/EJ9Pvi6EKTnKul8VOj8aUxSGmHE25gbAzw1p2Q+n1dFouejlGHy3c/CUHB?= =?us-ascii?Q?w1LIH7YA28oQVE+imFqmye0/FQdyAWESI4mAKlvh+RTojtW1wjIdCa2+kBFJ?= =?us-ascii?Q?sy9ToDw1n7SadpcfU2JFpJHvEKsF6AjAybkqg/faz4FBC908jwW0e+xUIWPd?= =?us-ascii?Q?PiZqR2+P7jhLq2fwy+c6qoaY+f3y7URcF+gxYaXjuwKh6Yi4KQeP3P/TPfsl?= =?us-ascii?Q?eZmu0meALv4DUeeefmEx4HknmSLTPOGntuegUGKjICK5mZFpryd3+OrVZm7s?= =?us-ascii?Q?peVObtzqGo/1CyXiVQ9G4JMXTTwRXKVvaCcIHpAF/fbk2i+AS9rV3y4JHPIp?= =?us-ascii?Q?XTiqhG87pbAIGn4GQ81N6nFTgIpIPrtRRd3kIaZUPT9RDLnAqfxX6VUTGSiD?= =?us-ascii?Q?s/6pva2NQr4gPqze/61Go2rmUkDDmHSwULB9uCkKT2cFtcofQOKGyzvTMHzL?= =?us-ascii?Q?ZLh4fq2xrK31E//9Gr6TxuZLgh80YYzmWX4jMR4a48IRSw5javUqansfhwsM?= =?us-ascii?Q?t0FHTfFKWOIGTPBF+/uU4Zd/0MdhwVoTgDA+ecyiYnVqHwox4szARszOmsOw?= =?us-ascii?Q?LIQMdCd+im9JX3GkAXXP+CcbPCChIvFgybTCv7xMM0+5w2tUk6yfvuRLCQPu?= =?us-ascii?Q?iOicUqbvzrPp+7iXbxzBFhm8vc88uyjd8sy/+KxTjJu5eaa4+btSOlxvWGtp?= =?us-ascii?Q?lt/TMt1QHrasiBZwz2GGw5sUBTf7Wshv+P3hWCtzbtggsYav1UwfZIxs1O3x?= =?us-ascii?Q?b7y+H0gNthVz2oXi/VOOsIGWRvP4q7/B+1XoJnIN?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6400afee-d956-46ca-8d20-08ddc6236dd2 X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Jul 2025 17:49:22.7207 (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: Ld3t8Ia+vevaVgV2/9t0MKfsOGjcB8psYItYlUZEST+YPpBzceqUSxNDqibzDLrV X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB8739 On Thu, Jul 17, 2025 at 06:04:04PM -0400, Donald Dutile wrote: > > Implement pci_reachable_set() to efficiently compute a set of devices on > > the same bus that are "reachable" from a starting device. The meaning of > > reachability is defined by the caller through a callback function. > > > This comment made me review get_pci_alias_group(), which states in its description: > * Look for aliases to or from the given device for existing groups. DMA > * aliases are only supported on the same bus, therefore the search > * space is quite small > > So why does it do the for loop: > for_each_pci_dev(tmp) { > > vs getting the pdev->bus->devices -- list of devices on that bus, and only > scan that smaller list, vs all pci devices on the system? Because it can't access the required lock pci_bus_sem to use that list. The lock is only available within the PCI core itself which is why I moved a few functions over there so they can use the lock. > Could we move this to just before patch 11 where it is used? Yes > or could this be used to improve get_pci_alias_group() and get_pci_function_alias_group() ? IMHO it is not really worth the churn Jason