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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: i6nj1JYAwMDsFRs/E1yopvr3MyQfi4CU13mDAhy7cUuqB1XFrejs1YJ+l+42N8Fz5J7tPLpNYbpgOVjARikN1uIElsFGoGTyYOe6y7PxwqsetXb4lZKm3OMVyCsrTjKqwxIJwRril3SEECVZK0hIupTLKqcrQwc1v+iBCuNN8GXCFhWZUKBUt8wFefBx809kD/KeIRCXwmHHJ2KXqyqcTqaHq2wy6OjvGHqIJF5t6SqId1X6cxXMAGYO8lBPnhOCaqVFqY84qt0a0OYE1qnBN9xkSJkNd5JFiOM7sZe/WrNGvnhDtA8Yt9Y2QGQgGJxO+gTLN7ayCOaeYKG8Ge1CdxG9IGeyKZEwE6HZt+OK9fmsLkPPKqUzUsX1zzobs43W/aPcbtQygTmBLTfNUikzUYJ1xjL23QTXGyL+4xFwXs5HtEc58e2Ijcr8ZYrqYx8q X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Feb 2026 05:16:34.3673 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 61337eea-5556-4a3c-f355-08de68638f18 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: SJ1PEPF00001CE2.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB9734 Hello Peter, On 2/9/2026 9:17 PM, Peter Zijlstra wrote: > I ended up with the below; and I've already pushed out a fresh > queue/sched/core. Could you please test again? I haven't seen any "sum_shifts" turning non-zero on the overnight runs, even with the larger workloads, so feel free to include: Tested-by: K Prateek Nayak The overall patch looks good. I only have couple of cosmetic nits inlined below: [..snip..] > u64 avg_vruntime(struct cfs_rq *cfs_rq) > { > struct sched_entity *curr = cfs_rq->curr; > - s64 avg = cfs_rq->sum_w_vruntime; > - long load = cfs_rq->sum_weight; > + s64 delta = 0, runtime = cfs_rq->sum_w_vruntime; nit. "runtime" is only ever used in "weight" != 0 case so perhaps it can be moved there to preserve the reverse x-mas (or this whole line can be moved up top). > + long weight = cfs_rq->sum_weight; > > - if (curr && curr->on_rq) { > - unsigned long weight = scale_load_down(curr->load.weight); > + if (curr && !curr->on_rq) > + curr = NULL; > > - avg += entity_key(cfs_rq, curr) * weight; > - load += weight; > - } > + if (weight) { > + if (curr) { > + unsigned long w = scale_load_down(curr->load.weight); > + > + runtime += entity_key(cfs_rq, curr) * w; > + weight += w; > + } > > - if (load) { > /* sign flips effective floor / ceiling */ > - if (avg < 0) > - avg -= (load - 1); > - avg = div_s64(avg, load); > + if (runtime < 0) > + runtime -= (weight - 1); > + > + delta = div_s64(runtime, weight); > + nit. Is this empty line necessary? > + } else if (curr) { > + /* > + * When there is but one element, it is the average. > + */ > + delta = curr->vruntime - cfs_rq->zero_vruntime; > } > > - return cfs_rq->zero_vruntime + avg; > + update_zero_vruntime(cfs_rq, delta); > + > + return cfs_rq->zero_vruntime; > } > > /* -- Thanks and Regards, Prateek