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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Oct 2025 06:29:41.3980 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: c11bef17-ab90-4a4b-2585-08de15223625 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: SJ1PEPF00002310.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH2PR12MB9496 Hello Tim, On 10/11/2025 11:54 PM, Tim Chen wrote: > +/* > + * Do LLC balance on sched group that contains LLC, and have tasks preferring > + * to run on LLC in idle dst_cpu. > + */ > +static inline bool llc_balance(struct lb_env *env, struct sg_lb_stats *sgs, > + struct sched_group *group) > +{ > + struct sched_domain *child = env->sd->child; > + int llc; > + > + if (!sched_cache_enabled()) > + return false; > + > + if (env->sd->flags & SD_SHARE_LLC) > + return false; > + > + /* only care about task migration among LLCs */ > + if (child && !(child->flags & SD_SHARE_LLC)) nit. You can just check group->flags here. > + return false; > + > + llc = llc_idx(env->dst_cpu); > + if (sgs->nr_pref_llc[llc] > 0 && > + can_migrate_llc(env->src_cpu, env->dst_cpu, 0, true) == mig_llc) > + return true; > + > + return false; > +} > #else > static inline void record_sg_llc_stats(struct lb_env *env, struct sg_lb_stats *sgs, > struct sched_group *group) > { > } > + > +static inline bool llc_balance(struct lb_env *env, struct sg_lb_stats *sgs, > + struct sched_group *group) > +{ > + return false; > +} > #endif > > /** > @@ -10954,6 +10988,11 @@ static inline void update_sg_lb_stats(struct lb_env *env, > sgs->group_type = group_classify(env->sd->imbalance_pct, group, sgs); > > record_sg_llc_stats(env, sgs, group); Okay, I see the intention of recording this based on group stats. Sorry for the noise on Patch 2. > + > + /* Check for tasks in this group can be moved to their preferred LLC */ > + if (!local_group && llc_balance(env, sgs, group)) > + sgs->group_llc_balance = 1; > + > /* Computing avg_load makes sense only when group is overloaded */ > if (sgs->group_type == group_overloaded) > sgs->avg_load = (sgs->group_load * SCHED_CAPACITY_SCALE) / -- Thanks and Regards, Prateek