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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?ms6RWndnjIOoJxlrgPY9KiwcysUs7HlW8/oqM8HrWrqMaSL+fr89XSKRURtq?= =?us-ascii?Q?hyAJQTS40TiptjZcYhZMlGJoBSGaetBXQAjKBC0iGDjxzNSs/1KSiGbzpyQM?= =?us-ascii?Q?dk4p5vtd8CIustSGQyIGjSZGyCuq2hRubgymzzEajXk2qmS/joFwW9ZPLJTq?= =?us-ascii?Q?hypAZJb8HUfO1ZON40TUn4b3qqua6LFrT82wSJXvCNnjXueJOhGqpt0AQqRN?= =?us-ascii?Q?zkt2VE3N+PooNKQ3jBHs0rrjXxLEyrvQ7BoF4v+MtiFB6qZWrV10nV9cb2lo?= =?us-ascii?Q?kLNKrQgb3TZp7bvk85RQsTDGTdHUfg2vzvwQuOeXb1HGuRo8OcgueKXl6bWX?= =?us-ascii?Q?cg7wyIv1fp9PM6sH4Ld/t29wRIPmx5eYuD8gEjR/RVcZhU9cNzNYodE9dy5U?= =?us-ascii?Q?Ia8WaAgyXuVQgR6dzOltlaUb4a24jg7WrEh/rSigGW8K6NW+C4fStk71XaFi?= =?us-ascii?Q?wp+9LTpohgr/qd1/PsJYpqjaL7ckY/IHKJsnpJQcCVOXGEONQT261tZ4sjop?= =?us-ascii?Q?zo102iWiT1Kdj7OAGvG7XmWxCIhFhM8xBSBSbBwMYvVNM8sUZfgxO32gzmqt?= =?us-ascii?Q?FFX3CpOSYSk0S9yxdUdZ5Mee9ZyqPTEfeZd3mAoU2UcVTS91ZtWkTbF4DHiq?= =?us-ascii?Q?3LdRLsBmkX1tDeLyqhg/cwGWj4fYPQxvi7JUbcRyswR3KdwZk1j9uzsmciow?= =?us-ascii?Q?gvUAfAM7GKmJOQEqc4iC6XBE/tKOj5/y76TFYFkzWy4IMDX+8Tjmy8K0CVjr?= =?us-ascii?Q?Uza1qTDm9lJVqI7pJUgxDo1GtCrRV++sgnLFJlrrhzsSkqEoBshvTf2shGnU?= =?us-ascii?Q?bYY/7qLRGj6cAlCj1fTxnguNZGNWJp34qXsgpQxO/IO9qr8Io6QlCKyX6KMC?= =?us-ascii?Q?U3/V9cSOB66tuorHcZWjZu8ZhWZ2Viqbt/zV3lJ5p57O0Dv8OjsdodtL9s3E?= =?us-ascii?Q?fh9e4sLyACmm2nWfinRyppfFA26NjpaHDU1PJwqRNnSyczS+RGW4auQW3I4H?= =?us-ascii?Q?u5xQJ+dq+meYI4OIBmspb0/JEB7SK3+s9merSrvAO+gQTVebhYUh5JzVo+QF?= =?us-ascii?Q?a5/WEoyCeeKBJ06WFf8BYHzOJnXk2CgnO2t5F5tsYMBTrML6U+1Ucd3tjk2s?= =?us-ascii?Q?e5TIGs3q7kT/bKlPSLy+N/WUTN/e2kcob1fE3xa0OIFD5fZgQTPeUg2dYeAi?= =?us-ascii?Q?SZTrHY04kS/n3yC2xXZ8zJ5rCMpgvt99Zrcbnbj9NMwVXErWQO6BQVlLLR/o?= =?us-ascii?Q?FWBfpAWUJDExZwO6G+5Cq+I1vb2I0r0dckmRIYB0Idn5gwYHKnXtf6NzV4dt?= =?us-ascii?Q?6tBinPEfkQdQIDD+TbvIw6XxsAJCPjA/R960EtG5wj+2yfjNNf3LjZJpdsrG?= =?us-ascii?Q?j9IsMuvhxxvsWYe5idSl3HKTYQH7SvoCpHz5k9UZHHUPoiupxfdjxnOCsJRD?= =?us-ascii?Q?LyIt7zKSNHUdb66DR1ItFnpAg0+bxBDC3kFOaNqzxc/q7P5eVabsOi6+nNFp?= =?us-ascii?Q?dutJdt9wv8/OPDcXFwV3Ag+puYjWr9rhut+kYGdrU2OOZamW23NNhxQ/4L2p?= =?us-ascii?Q?wnVNfYu4okXPBp+OWVr2UU4045diw62DRTcYgHmg?= X-MS-Exchange-CrossTenant-Network-Message-Id: db532a23-3134-488b-d519-08de32bb1e2b X-MS-Exchange-CrossTenant-AuthSource: SJ1PR11MB6083.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Dec 2025 22:27:18.0975 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: PTilbGnuFPZXtzjrkffk5eMsWVd7S6xk+l/IP2hA6QmJ71yen2Q4bx+Gf3oOSD2pUUutptVsocegQBLLhixCOw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR11MB8275 X-OriginatorOrg: intel.com On Wed, Dec 03, 2025 at 01:21:56PM -0800, Reinette Chatre wrote: > Hi Tony, > > On 12/3/25 10:04 AM, Luck, Tony wrote: > > On Tue, Dec 02, 2025 at 08:28:56AM -0800, Reinette Chatre wrote: > >>> diff --git a/arch/x86/kernel/cpu/resctrl/intel_aet.c b/arch/x86/kernel/cpu/resctrl/intel_aet.c > >>> index 46c64419ec10..50c8b4c50790 100644 > >>> --- a/arch/x86/kernel/cpu/resctrl/intel_aet.c > >>> +++ b/arch/x86/kernel/cpu/resctrl/intel_aet.c > >>> @@ -57,12 +57,16 @@ struct pmt_event { > >>> * struct event_group - Events with the same feature type ("energy" or "perf") and guid. > >>> * @feature: Type of events, for example FEATURE_PER_RMID_PERF_TELEM or > >>> * FEATURE_PER_RMID_ENERGY_TELEM, in this group. > >>> + * @name: Name for this group (used by boot rdt= option) > >> > >> This needs a new definition since multiple groups can have the same name now. > > > > How about this: > > > > * @type: Type (energy or perf) of this group. > > I find this to be confusing when considering it together with existing @feature and its > definition that also refers to itself as a "type" using perf and energy terms. Agreed. The two fields duplicate the same basic function. > > > > That covers how different instances have the same string where "name" > > was confusing. > > > Essentially this is the name used for @feature and for this there is already > pmt_feature_names[]. Is it needed to create a new name? This would mean that the > kernel parameters become "per_rmid_energy_telemetry" and "per_rmid_perf_telemetry" which > is much longer though. The only limiting factor I am aware of is the command line size which > is defined in arch/x86/include/asm/setup.h as 2048. Here I do not know if there are customs on > whether kernel parameters need to be brief or not ... some kernel parameters seem to be quite > verbose while others are cryptic. Personally I prefer brief names (as it isn't always possible to cut and paste to a remote serial console window to add them in grub edit mode). > > The safest may be to stick with the separate names but I am curious about your opinion. Short names are good. > Even so, it seems unnecessary to force each new instance of struct event_group to > set a parameter that is required to be of particular value based on value of event_group::feature. > If not using pmt_feature_names[] then intel_aet.c could have its own private array > that maps pmt_feature_id to "energy" or "perf". I find that doing so would make it obvious > what this property is/should be. > > What do you think? I agree with one value and a mapping function. But I'm using the string name eight times, and the event_group::feature just once. So I think I'd like to keep the string name in the structure, and just do a lookup of the enum in order to call intel_pmt_get_regions_by_feature(). So new proposal. New name event_group::pfname for the string: @pfname: PMT feature type (energy or perf) of this event group. static enum pmt_feature_id lookup_pfid(char *pfname) { if (!strcmp(pfname, "energy")) return FEATURE_PER_RMID_ENERGY_TELEM; else if (!strcmp(pfname, "perf")) return FEATURE_PER_RMID_PERF_TELEM; pr_warn("Unknown PMT feature name '%s'\n", pfname); return FEATURE_INVALID; } There are only two options, and no sign of additional ones. So this if/else style seems simplest, rather than creating a lookup table to iterate through looking for the feature name. -Tony