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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 Nov 2025 16:34:09.2858 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: eacadc56-2e61-476b-5d35-08de1c89253f 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=[satlexmb08.amd.com] X-MS-Exchange-CrossTenant-AuthSource: SJ1PEPF00002325.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR12MB8786 Hello Fernand, On 11/5/2025 8:55 PM, Fernand Sieber wrote: > Early return true if the core cookie matches. This avoids the SMT mask > loop to check for an idle core, which might be more expensive on wide > platforms. > > Signed-off-by: Fernand Sieber > --- > kernel/sched/sched.h | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h > index adfb6e3409d7..381cd561e99b 100644 > --- a/kernel/sched/sched.h > +++ b/kernel/sched/sched.h > @@ -1432,6 +1432,9 @@ static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) > if (!sched_core_enabled(rq)) > return true; > > + if (rq->core->core_cookie == p->core_cookie) > + return true; nit. We can use sched_cpu_cookie_match(rq, p) to check for the above two conditions. but even this is good. Apart from that, I think this optimization makes sense. > + > for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) { > if (!available_idle_cpu(cpu)) { > idle_core = false; > @@ -1443,7 +1446,7 @@ static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) > * A CPU in an idle core is always the best choice for tasks with > * cookies. > */ > - return idle_core || rq->core->core_cookie == p->core_cookie; > + return idle_core; Peter, do we care about checking the core_cookie again before returning just in case the task cookie was selected between the check above an here? If not, then this looks good to me. Feel free to include: Reviewed-by: K Prateek Nayak > } > > static inline bool sched_group_cookie_match(struct rq *rq, -- Thanks and Regards, Prateek