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Wysocki" , Frederic Weisbecker , "Christian Loehle" References: <20260301191959.406218221@kernel.org> <20260301192915.171574741@kernel.org> Content-Language: en-US From: K Prateek Nayak In-Reply-To: <20260301192915.171574741@kernel.org> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SJ1PEPF00001CE2:EE_|LV2PR12MB6016:EE_ X-MS-Office365-Filtering-Correlation-Id: 85f55a97-cf20-4aa4-c920-08de7821bed7 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|82310400026|36860700013|376014; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:satlexmb07.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(1800799024)(82310400026)(36860700013)(376014);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: N+cRnHwhsOuxUX7FpIXLVAgBF1UvVqyJeoaOQ9e0tJHOmpV48en8dxnevc1gFsQrJRfOsiaWyEDcSxWXpd+kkz6uGyfpWO4r2uWU9kilVXTV6bJSADIQ4FXoLzOhDKKMW65kpFd/77n+EgMiXnv9uaKIpBPDicAECIeZuk7cvtPM2ds0GcUOGYZ9uBqie27IN4l+V2ZSqn2PLpMWYJntj8Mlz+gaOknkb9ZkjkmGa428mdmtONuTbiJmk+W3d/TGOT6WkVrtZ2bwT6DiYALfHzCKMYTGDGGaOvklUzuRdn+pS0xPqH1tHZkLaXYIGprRy6ELMx8wsJWssJh7h7yJ5RVwKFHLDAY3/sPujUQi8y1pjNzgTu5Mgg665km7aliRtltdzish6A822LFlsXHlXxZwfmiFWrJ/mIM43yu3F9WYjahcTgEPvEg6CVjpXSSa X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Mar 2026 06:05:46.2995 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 85f55a97-cf20-4aa4-c920-08de7821bed7 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: SJ1PEPF00001CE2.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV2PR12MB6016 Hello Thomas, On 3/2/2026 1:00 AM, Thomas Gleixner wrote: > +static void default_idle_enter(void) > +{ > + this_cpu_write(nohz_data.entry_time, sched_clock()); > +} > + > +#else /* CONFIG_NO_HZ_COMMON */ > +static inline void default_idle_call(void { __default_idle_call(); } ^ s/void/void)/ to add a closing bracket here for !CONFIG_NO_HZ_COMMON. > +static inline void default_idle_enter(void) { } > +#endif /* !CONFIG_NO_HZ_COMMON */ > + > static int call_cpuidle_s2idle(struct cpuidle_driver *drv, > struct cpuidle_device *dev, > u64 max_latency_ns) > @@ -186,8 +236,6 @@ static void cpuidle_idle_call(void) > } > > if (cpuidle_not_available(drv, dev)) { > - tick_nohz_idle_stop_tick(); > - > default_idle_call(); > goto exit_idle; > } > @@ -276,6 +324,7 @@ static void do_idle(void) > > __current_set_polling(); > tick_nohz_idle_enter(); > + default_idle_enter(); Can we defer this to until after do_idle() disables IRQs to avoid a per-CPU write when we exit out immediately if it is semantically same? As a bonus, we can then use __this_cpu_write(). > > while (!need_resched()) { > > > -- Thanks and Regards, Prateek