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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?zjazgEV8erwXLgRDAE+yMRlUXSGeTgW/i7HAM897mItjOma4vN0cuEiR6wDI?= =?us-ascii?Q?qixRJ/JSfzzJ7iY16BrCsKfchBjozJqmlnqXwwY/l77iXJ64xNyjNZtu1Q/c?= =?us-ascii?Q?b6rvGg0K0WIsvnuthAzQIMC4QsPQhJtvnHdH5ivWRx3zAEqTxBWnYDKPI9AD?= =?us-ascii?Q?dHBH4MFyihO7MD3+jb1TaXBHYMxJop6VzDWbzcnnrP/iOzinBh39i6h4V+IQ?= =?us-ascii?Q?bg3MSPE5KjjhRcBCPgKTDri87dfd/F2/GaAvN7qo47NNBxmhmspeNGUrj8Gz?= =?us-ascii?Q?2JkX0H9mC6f9HgY+UdkqsZpMSswJyhKSfzPfQdZtDZuXoeH0/0uV5l7fMScb?= =?us-ascii?Q?b6/mSAyt0YGrDJsK2AGsHbpdkLebrAH+cr3lUoHv82UUiDk7eoACzO/x+7E3?= =?us-ascii?Q?8EIDRFqE4Turs/1DHOzu1Wd8LiImmmu+CP6GfqXNdFZZ60+WzwTfniMPrltL?= =?us-ascii?Q?8ZVji/yNjXbZszREMKk0EtNV8Zbo6McWlaSdbuz77gAGeMzzaKAzzY4jsrts?= =?us-ascii?Q?beDPBS6v3kqcomcd1zhiXSMgzkOpJoREXnFvlfbHnWyLZcj2RO7gQ1eROfft?= =?us-ascii?Q?SPkEpz3GSREW6rkEU2WUdubD8uehtPLqnqUGrJdauIWaBinTH8dtSMMMMB4f?= =?us-ascii?Q?HUY3M114lcpIBRPOi/jt0IurVA1Nn+xZOC2e2hD0BhUAPRHIVd54mUE/RMAP?= =?us-ascii?Q?sp1FvXvGe0uSm/a1lJF+xg2K6ghTzbSDMuZ+Nydy4O3RAudsSfd/yZbYNRy0?= =?us-ascii?Q?L0o/8+DdPjth1HcCIqe1SgkL1oaYwgahrj6XqZy73KwhSMBYZKT95e8OzdNe?= =?us-ascii?Q?p0skc561paEaNCiUEduF/A7hqpxEf2XKi7vKMolmLrkeqOOwRwdz/Jf+oDw6?= =?us-ascii?Q?NUIahMXLkWrh9ZA+UGNqbj6k4QLDVhqWkbMKPnU7yp7OoaODcX6Eu/tkrEnO?= =?us-ascii?Q?wnYS0SAZrAEX3K0iJlnOR/8EgSi8iKPfwF7lplyZ/9+TK/hRJ2B0K7nsGRSk?= =?us-ascii?Q?rKwZPZRYcLX1qsNzy5/MFSHmpNylfJqx9H0PiQ3t9ZpaoczATDpf0NFt0NO0?= =?us-ascii?Q?5RYousKBLNKeNl0XxmEtvugGyPTkVy2dfI6Z3lPRghz18/aYceug0j6xbVkN?= =?us-ascii?Q?lzVu6lL1gD764xiLw5nxGIm5ilu3a7O17crm/FYclJPhEq6cBOC49TEmOnhH?= =?us-ascii?Q?9IIHg1Vp9BNXl5xIUNJE0a5h6SFMLBC8/55QghqVcOfbrgmcxknuiL5AqRVt?= =?us-ascii?Q?947l+NdN64A8SybyWu3dYEJmH87R66ThHFJxsxR4+oTnKsfEGkBWLyRexlyv?= =?us-ascii?Q?6KwQPkP8uYhf5lemw5KN6Aj9JCikbtU0EDMeZ0hmUKszJqrTZ9p8KxmCgSSr?= =?us-ascii?Q?e7yeIA5247KJhpyGgtWpFRdfOujhzSGYHrPNoaatG50V8OKkNo+Y3ujIxcXw?= =?us-ascii?Q?21Y5m4G6F7J87Unz9DOzjzD5JuRlnebBAO6LypKz30qGJM5BNKFrTjn6YZH5?= =?us-ascii?Q?NH2R+cAFs0gIcCr5+SAIru91xGI4Ru+QEOpZlPiiFjS5nyuPvI2X3eoGPN1Y?= =?us-ascii?Q?PeuVv3+eb935lBLCFY+I9Dwx1souo+YTa6EbCBlQRA7QJ0dOVsjuOupmOKAe?= =?us-ascii?Q?lRrXZMOz660kFA1HUIkW9xQgGEKNSQAL/dYrx9kOVx0eRodVdE9oErK2VcX6?= =?us-ascii?Q?IhUCZMnD5LAb3ayZN/kUniE88+SSa7AKHIFc4LGLowOSKva1nHPtKTAEKDNy?= =?us-ascii?Q?i6YDHLmCrQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 14a2adde-437c-4941-f45d-08df07848182 X-MS-Exchange-CrossTenant-AuthSource: DM4PR12MB5230.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 31 Aug 2026 17:23:00.1335 (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: TITnZ2evMjdzbbfq/Lr8oa+9g/zjJK/rZYhHiW/fJUJxLKcIjJBJ0MiJmQtLOzNsLBl3j/Nk+EU1/3vz/oWgDw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ5PPF0C60B25BF After enabling memory-level MSCs, the existing class-picking heuristics still treat every candidate like an L3 cache MSC. That rejects valid memory classes for MBWU counters and applies L3 egress checks to MBA classes on CPU-less or system-wide affinities, leaving no monitor or control class selected on affected platforms. Adjust the heuristics so memory classes can back MBWU directly, L3 topology matching is only required for level-3 MBA candidates, and traffic matching is skipped when the class already spans all CPUs. Also tolerate components with no online CPUs once at least one component has matched. Signed-off-by: Shanker Donthineni Signed-off-by: Fenghua Yu --- drivers/resctrl/mpam_resctrl.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/drivers/resctrl/mpam_resctrl.c b/drivers/resctrl/mpam_resctrl.c index 47a7b18d841d..72302f6021d7 100644 --- a/drivers/resctrl/mpam_resctrl.c +++ b/drivers/resctrl/mpam_resctrl.c @@ -865,10 +865,12 @@ static bool topology_matches_l3(struct mpam_class *victim) { int cpu, err; struct mpam_component *victim_iter; + bool matched_once = false; lockdep_assert_cpus_held(); cpumask_var_t __free(free_cpumask_var) tmp_cpumask = CPUMASK_VAR_NULL; + if (!alloc_cpumask_var(&tmp_cpumask, GFP_KERNEL)) return false; @@ -882,8 +884,11 @@ static bool topology_matches_l3(struct mpam_class *victim) } cpu = cpumask_any_and(&victim_iter->affinity, cpu_online_mask); - if (WARN_ON_ONCE(cpu >= nr_cpu_ids)) + if (WARN_ON_ONCE(cpu >= nr_cpu_ids)) { + if (matched_once) + continue; return false; + } cpumask_clear(tmp_cpumask); err = find_l3_equivalent_bitmask(cpu, tmp_cpumask); @@ -903,6 +908,7 @@ static bool topology_matches_l3(struct mpam_class *victim) return false; } + matched_once = true; } return true; @@ -1041,13 +1047,15 @@ static void mpam_resctrl_pick_mba(void) continue; } - if (!topology_matches_l3(class)) { + if (class->level == 3 && !topology_matches_l3(class)) { pr_debug("class %u topology doesn't match L3\n", class->level); continue; } - if (!traffic_matches_l3(class)) { + /* Check memory at egress from L3 for MSC with L3 */ + if (!cpumask_equal(&class->affinity, cpu_possible_mask) && + !traffic_matches_l3(class)) { pr_debug("class %u traffic doesn't match L3 egress\n", class->level); continue; @@ -1175,8 +1183,9 @@ static void mpam_resctrl_pick_counters(void) } if (class_has_usable_mbwu(class) && - topology_matches_l3(class) && - traffic_matches_l3(class)) { + ((class->type == MPAM_CLASS_MEMORY) || + (topology_matches_l3(class) && + traffic_matches_l3(class)))) { pr_debug("class %u has usable MBWU, and matches L3 topology and traffic\n", class->level); @@ -1314,6 +1323,9 @@ static int mpam_resctrl_pick_domain_id(int cpu, struct mpam_component *comp) if (class->type == MPAM_CLASS_CACHE) return comp->comp_id; + if (mpam_class_memory(class)) + return comp->comp_id; + if (topology_matches_l3(class)) { /* Use the corresponding L3 component ID as the domain ID */ int id = get_cpu_cacheinfo_id(cpu, 3); -- 2.53.0