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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?KAEfeULMD3FJabzeb6p7KAxEAN6NK57rroBtIit6TKcg9G3pUuRziCHTBMHL?= =?us-ascii?Q?6hgrI/EowfXsQ4yVI6vbo5OCP8beHHr2xU97UrphGgjkqJ9MuGT2vwVCO/DY?= =?us-ascii?Q?PQaixyEjMhKo6ruaPhiMhQxRRXjaq9ylBPz7ss5pf2hixV6vWXcdgPj7H+ve?= =?us-ascii?Q?vVwcHSXlGNHW5UajPBcsuRWkjd0mmw6JC2Gl1xo4/VEx0+tJYT3LpmiyFWwE?= =?us-ascii?Q?c6PwLIcvVhrNQ8wFt9QFWoRSojs82tBKOhGOEOBsvMkaBrxk1zcbRu/O2Hp2?= =?us-ascii?Q?8RS44eYS3fp16bH1Tfcf2TlzZ8/woyhiQTPyF+tFe5kj/yG3ZcdD5UD8Q8hI?= =?us-ascii?Q?+Q3QPeZHHPgRR842Ak3305/eaHNaQQ6Y9d/cWk4B+YG2E8jo3PzCyZ+iT0UW?= =?us-ascii?Q?5tNTFQlphPkz/aZcPyFZcc72TwobXB0HUJOI+m3jUwd+fo3ATLwiuQFDghbf?= =?us-ascii?Q?yHNklDtZGqtcr63uzLTBXMjclk7QX/llRO2l7wOum1aBUoqLwtKR0o5w3+T4?= =?us-ascii?Q?/rxTyY21eLG+w/2AfzuVWVV2faTkzd42tP5AggicL0TfbarmaXEeBZRHvWny?= =?us-ascii?Q?w1esGqIYckq4VNGNDtydIFVYAxZyDFG2Lf3g946BNPRhXf7dJGALDYyuRXHv?= =?us-ascii?Q?R5fEKK0BsNZXcPR2tT4hlQC1r1HYL+6JNx168rfecOQB9JVXLrAjFu/LXBoP?= =?us-ascii?Q?x5Dudx1mu9xFh3HJ9yFGfBJ9IxHGLGy/NHxoVpat8vpoSYzkiYeNjtSlOubH?= =?us-ascii?Q?xJlkcUcm1BhrCQ6xKgOCC7fyjg1fUdk6l+H6YuWZzL/8EIaI8vtCx3QknAUS?= =?us-ascii?Q?0qX/muK/jdtEJiegiJr7/YCVHKe3mFQawT8I0FR0FXxfAeafIXKASeQX9Br2?= =?us-ascii?Q?uzdo2IdsDNxL88Sd8dU7vK0ZcgCUFwv+F6csxSBFWyX0ojp/8MHRfgExfWPI?= =?us-ascii?Q?4eskkklP1KWbemfnD5E3fUUg8dAUjnHb4R09Qc47qfi9EByFphX5XXOr3Amj?= =?us-ascii?Q?JI7fRhmrHKXw+9lf/qEWcALJiskVPO3LgqYltlW6v5M9pQVbDWSxDYx7Kzk/?= =?us-ascii?Q?1l1CEXtLCgrnFaFlazkUbREhHn1OfQa8CT1N2Tn5J5QITJzH3M9UBmXzerfn?= =?us-ascii?Q?7w7hw+e+a/v0QyUkmfJpsAqo6F+OMNNG02XzPF5/zo87ZnHWiXZLGLLfTH1E?= =?us-ascii?Q?ihrj7zkdIIYDf/AEaV2Cbxxt5sSArLrCykUclrO2NZS/lkcMWDZmvZgUeTm6?= =?us-ascii?Q?8AnEHn94/av9rXSNujtz6/8V+OvNzQ1oLufyaeeUQcyVJAe+ci20Ic1h/zCi?= =?us-ascii?Q?vzl+lTZuHMosqrfekEyHRtl40l2vH/YU9fNfYsLzQdRDqbsW065QFpmltdco?= =?us-ascii?Q?4cmmrzKP2gNLZHdWQWRAA0W8Lj5IhSczf0CfrQOCDM1DoI1q2qoRRGpd+wk0?= =?us-ascii?Q?VIBJUEPofWBXyrSqz0ScQOLm6bv5424KhBYaKDQ/dGjgSHKe2or9Zy+GEOEa?= =?us-ascii?Q?xHGmSFomOId4te2Eu7CsL8jsIIjCxz2FEC4eZHq1MWy30VgEgrkdGcSfpsWq?= =?us-ascii?Q?6bqIT9vbWf+Ft3IAu/pviljrAILH3HQMfd7ZR0Yt?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 0aaab73c-b28d-4bf0-a21b-08dd5d423f8a X-MS-Exchange-CrossTenant-AuthSource: CY5PR12MB6405.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Mar 2025 06:35:27.3349 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: ueaxjOUuFReH2BJHpYqy0NLShr4rvpLj+zNrgmCdSFCP0kFjBOOoR2zsZsL+4ASCYYNI94yMojMtzYcHDWnYUw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY8PR12MB7415 Hi Changwoo, On Fri, Mar 07, 2025 at 12:15:04PM +0900, Changwoo Min wrote: ... > > +__bpf_kfunc s32 scx_bpf_select_cpu_pref(struct task_struct *p, > > + const struct cpumask *preferred_cpus, > > + s32 prev_cpu, u64 wake_flags, u64 flags) > > +{ > > +#ifdef CONFIG_SMP > > + struct cpumask *preferred = NULL; > > + bool is_idle = false; > > +#endif > > + > > + if (!ops_cpu_valid(prev_cpu, NULL)) > > + return -EINVAL; > > + > > + if (!check_builtin_idle_enabled()) > > + return -EBUSY; > > + > > + if (!scx_kf_allowed(SCX_KF_SELECT_CPU)) > > + return -EPERM; > > + > > +#ifdef CONFIG_SMP > > + preempt_disable(); > > + > > + /* > > + * As an optimization, do not update the local idle mask when > > + * p->cpus_ptr is passed directly in @preferred_cpus. > > + */ > > + if (preferred_cpus != p->cpus_ptr) { > > + preferred = this_cpu_cpumask_var_ptr(local_idle_cpumask); > > + if (!cpumask_and(preferred, p->cpus_ptr, preferred_cpus)) > > + preferred = NULL; > > I think it would be better to move cpumask_and() inside > scx_select_cpu_dfl() because scx_select_cpu_dfl() assumes that > anyway. That will make the code easier to read and avoid > potential mistakes when extending scx_select_cpu_dfl() in the > future. I agree, will do this in the next version. Thanks! -Andrea