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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?2OLtosh2NGuXYAZBgP4WiSWrPTRCI4oXonwkJBZZ7WeUCGHi/VzQV47FNNwm?= =?us-ascii?Q?5EoicDrSmDf/SyRkrW5E4soNooEGHcGavgxLt/Z9a2UtQeMOY26z8qKo0PTC?= =?us-ascii?Q?yUzpVWQ00SDeKWD2KpQtpmrso/VieLihhx6XR5aqU0noqJx4iYEfwVJ2ipw8?= =?us-ascii?Q?S8ZOBxRtQGSWMKhQiBoEMJUspnZ3vuv5KCH64S0JGBgNU5Jrx/g5ZZq6WXi6?= =?us-ascii?Q?mvhJYk8T+t+CYnkkB8cMeeL6n+fQqm89sqrKHvuL4AKqYRFgQEuPnwPeLKfa?= =?us-ascii?Q?E+nJArwmgv6g7Zgx2lejdvEAnQumGC4WUFWdHqa0kGScm9D4Qi2V+u53vxIC?= =?us-ascii?Q?oOJdaDeei8YmLyuFEJbPeDTkGwGpIedxt10iai5GA3stMJnxuYDpFsC0yrq1?= =?us-ascii?Q?Hqp9rC/TzASQcCFCGZGTxVb1GQzqhjwO1nNFCb0Q7hPG4TOGeOMBHPxK4b9Z?= =?us-ascii?Q?1xKAiDtsDp65p00xgOIFwlCx6TNqbGrJEn2yIJKIhQPJLY+2iCG005Nu1Tm4?= =?us-ascii?Q?Nt1ivLJ5JcLY4hn3z/SZxfmeg5NHOGrixnnN6dmYdVH+AstvldX+Zseyant8?= =?us-ascii?Q?fnVki/lXQw2nMRdNyHwpxRKk+Kzn9i5Cj0SzMDyrY9olqhnAqTHXgCfYE6La?= =?us-ascii?Q?3zT5jtoXUjBobok+y4b7Rgn//+3kpn7/hOdEdZGsYdGN0Dppbv6h7Gcd+g3i?= =?us-ascii?Q?5WCYj8B2J/5EkvUMG0EvPEZlC3UA6B95GCmbr+kSC+3+dylxfLkv1EVnMH3f?= =?us-ascii?Q?Ca6XeBbpiPBjT2Gw7klX/ax6HD1vg6M/3vvx52o4DdLodS7XvJNiMltHZkfk?= =?us-ascii?Q?olcPsYwUnmqbk9rm8/po+nibD/0xtVHUq1+ZXi6dcGCJDq2BJ7GtLujaCumm?= =?us-ascii?Q?yYD0t4T4T5X+8rMC+2h3aNdrKFREieifmdEFh+ZixrL3AC11ghM0+Km7rRCU?= =?us-ascii?Q?xGGYwYHPPxJJKVdCajjmDSziTiNk3rCnLVnKR+Zgbk4PVEaZ95t16sGrwW9/?= =?us-ascii?Q?H4GCzSPCbYVZ6OnJ9Nw//mTZlWsvBnmfzVxNMpNx8CLGarodYREFecgK26dl?= =?us-ascii?Q?zgU1vLgUC4zc7f2gAVqsqeEZwFpX85RuLVpDneJiwayYFCtc7Ij/RyIvqgEx?= =?us-ascii?Q?bJuZF8Wn6SGIdeOw0xRrXnoeuP7Mm793j8HBQgpwe4kwzpVJsdWiOvJofynN?= =?us-ascii?Q?RGIhUvHjCFztinUb2LghbvJFybmpKU43CZ1ZIJjMP85gGFcBGKvvA4EzeXZ5?= =?us-ascii?Q?dgyhn6ZxStvbscyRebk6aatBpICgWuCzF7/xICB1X9H916NBLnipN0sRNyRM?= =?us-ascii?Q?gORJkiPCazZD5qfpKU7RX6w4AXUT8w3eFzZNPM0XlN+PU4MoGpBgMk7OkqCC?= =?us-ascii?Q?8D7RgAzi8RXubB5pIM/IEpr/dcYuApsk5peuegnUZguariuz4q7e5Y2N2ZFD?= =?us-ascii?Q?ltURntTMspobWZHgbziwRbunc9QYK6CJnBCy+9c9swP6n4B5+J6MvgEnpGDN?= =?us-ascii?Q?VJVeYW0nwYXN7RWFf7VNi10fO0G8eoD45z5WDoTOsOxtInlqifnPTUCfHHQp?= =?us-ascii?Q?ZmKshmE+qJjf9KqOHGTyhb0QtWPLze6J4FVqqbb1?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: a735d7c5-ecde-425f-602c-08ddfa7c5c8b X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Sep 2025 08:36:59.3431 (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: zP/9Tth+hv4vJ67xwcu/cTyX8D6pD7O4lCikMpYMjd7Ye/lA+IvfyZmQzI9GFm8sfQtovI0sdmxaTVvfezpf1A== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB8692 Hi Tejun, On Mon, Sep 22, 2025 at 06:14:36AM -1000, Tejun Heo wrote: > In preparation for multiple scheduler support: > > - Add the @sch parameter to find_global_dsq() and refill_task_slice_dfl(). > > - Restructure scx_allow_ttwu_queue() and make it read scx_root into $sch. > > - Make RCU protection in scx_dsq_move() and scx_bpf_dsq_move_to_local() > explicit. > > Signed-off-by: Tejun Heo > --- > kernel/sched/ext.c | 62 ++++++++++++++++++++++++++++++---------------- > 1 file changed, 40 insertions(+), 22 deletions(-) > > diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c > index 0c99a55f199b..32306203fba5 100644 > --- a/kernel/sched/ext.c > +++ b/kernel/sched/ext.c ... > @@ -3572,9 +3571,22 @@ bool task_should_scx(int policy) > > bool scx_allow_ttwu_queue(const struct task_struct *p) > { > - return !scx_enabled() || > - (scx_root->ops.flags & SCX_OPS_ALLOW_QUEUED_WAKEUP) || > - p->sched_class != &ext_sched_class; > + struct scx_sched *sch; > + > + if (!scx_enabled()) > + return true; > + > + sch = rcu_dereference_sched(scx_root); > + if (unlikely(!sch)) > + return true; > + > + if (scx_root->ops.flags & SCX_OPS_ALLOW_QUEUED_WAKEUP) We should use sch->ops.flags here. > + return true; > + > + if (unlikely(p->sched_class != &ext_sched_class)) > + return true; > + > + return false; > } Thanks, -Andrea