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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Jan 2026 04:26:58.1189 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: ed5bbb6d-b2ea-46a0-7cae-08de525bfd85 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: DS3PEPF0000C37A.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH1PPF6D0742E7B Hello Wangyang, On 1/13/2026 8:36 AM, Wangyang Guo wrote: > Read-mostly sched_clock_irqtime may share the same cacheline with > frequently updated nohz struct. Make it as cache aligned to avoid > false sharing issue. nit. Since you mention this is a "Read-mostly" data ... [..snip..] > diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c > index 7097de2c8cda..34d15972f5fb 100644 > --- a/kernel/sched/cputime.c > +++ b/kernel/sched/cputime.c > @@ -25,7 +25,7 @@ > */ > DEFINE_PER_CPU(struct irqtime, cpu_irqtime); > > -int sched_clock_irqtime; > +int sched_clock_irqtime __cacheline_aligned; Have you tried annotating it with "__ro_after_init" or "__read_mostly"? That should also ensure "sched_clock_irqtime" doesn't have false-sharing with the nohz struct without using an entire cacheline worth of space. -- Thanks and Regards, Prateek