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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?H9h1lxM0+Bo/9+3WD9Qi164Ew6rhg3Jj9MzAHrgSTNYZfe29fvZPhqVfdYHd?= =?us-ascii?Q?z1PVrrciB2cDVNy9aniV6h4k05AYJ2+1aRn7SbcaDA0icYWJOTi+3WSiCEkc?= =?us-ascii?Q?MrkKrwFTFBVcqxry6qZcUbRPgye/tXCbfc3rfYaV6Zmv/Xi4Eu0fSD9onXBE?= =?us-ascii?Q?FzKzjumVRefqaxcgAfN7W+gtJ4r2UPODjfAZp5leqbusGNpWKYSrcOGBT9CA?= =?us-ascii?Q?J0eBNymnPiG98zFUx/viToyLv9XhyV+NjGjvYbLjx5PnVLXc3+bu0D2Ihpui?= =?us-ascii?Q?LFGFuC2BLd0L1V0OZ4g5CbjogJsssNsXzNSwdTphNReDNgDLmJ32iXkTJPaX?= =?us-ascii?Q?K0/2l8GU4Knut/o047321WhiP0NLDr4m4YejVEQ9O30HRm9+UY3iXCmBMa7W?= =?us-ascii?Q?UxdVW0IeVK2G07EJUCY6cHIegkcEsZLY+IUe4S7c3Nn9YBd6Y4ZqONg/Z69Z?= =?us-ascii?Q?XmjkIOjaPR2pxSGRjx67rxPylG88CeHtuk8NX5oiZKq0tLMeOIeGQEX3kJn5?= =?us-ascii?Q?UjFInb5/JKEDyW9mXolc49XZJNBcmEN3jTm4I8NBJ59flbYD0et8hxz5UQ9n?= =?us-ascii?Q?xXKpEFHK1Sp8cUT1FwkV2ZxGLfd1ErBQIjXlWX2M1czVkQS0Ay2FBYLy5GnJ?= =?us-ascii?Q?+Mnjo20tzfpf1wE7Sk3dI0CgXMQVISsjKZLZLo1dATs9GqxrL5Vyx9GnRSXc?= =?us-ascii?Q?oZl0x1tm/8nUrMpGQ+GQ+hn14Mr+mRPHY9HKC1oF24+rsDvGf9jNHQ4agdjC?= =?us-ascii?Q?cDw+RU+bkAKbCwBFe5r7x6vzZg9WYBGjuOK5VKp8e2efgoIoRZqHGktsA3ig?= =?us-ascii?Q?oy4bFDtkJ9/jXlplJLXgg0b1s4ZgE3TJtWxIJoNmOurXLHlM2fyN02cJCBHM?= =?us-ascii?Q?x1HL2yrVwmhf9v1sBmYItjPy6PaDPN4n7b16dpgf4bPUZD3VpnM5ivxfHRG0?= =?us-ascii?Q?vrm1DPwM+LwV+PVREVXziBtuomYB0Tggjti/O/uoJ4y81sC9dvo2NFyBoznt?= =?us-ascii?Q?lN+WtMC51o6dar4y/WqRomUDZ39QPKZRDvZ18uKr/zixBP6P6DV9ZGuz8C7K?= =?us-ascii?Q?L+OhyKwvD7OuKqjs+wQNq+Xm3EUWfU5M9kWCuVy9nIOfQBJfwRI4add1oby5?= =?us-ascii?Q?8SaajvNalXzRj9e08BQ2gukw371LSXPTpibzpqYduV+h3xmlinsuazSmAeKW?= =?us-ascii?Q?Ta1lvGFSAAU13T8xb4Dg8/VFWcPq45IR0x+Pm7pacBSTojFbA33MPPICzZVx?= =?us-ascii?Q?aV5ALBY1v5aOHiR//VtCUtVuHI6/8HLFjB24Q8OgxeTno7y5zyG0MCV43qd0?= =?us-ascii?Q?2zzpMMY7Ce1Z1TaxCj5KMY/hH7SNQ+G3qtWmAljcfkCT+CtcPIPnL3hEc8YX?= =?us-ascii?Q?1UZoRfe/C+1fTGjRf03/eQU+slBotns7AqJCwGJ1r3kEPggjp5kCI8zTJl4r?= =?us-ascii?Q?Dytwrw7lZ1FooEF0l1FENrhzxo+0evroEiZajRX8P6FywT/fCfuQ4ky4E0bN?= =?us-ascii?Q?YQw9d2dcbK/VFv7qDXTXjb1d6SRJqNbG9rnNJqpkEfbcqQTskvoc64qrCdSC?= =?us-ascii?Q?GYq5AIxPlVHFwKfuc4TsaYyaO87Ul56xb3sexRosiZWF1fUCIQiqIIS2LxAQ?= =?us-ascii?Q?9zg8AXkmPGb63CtCSW3J+dt/oaUPCfaWk/+gR/chkHe04E9CWARgxq9Yqp5E?= =?us-ascii?Q?DTltSz8cXmYxIHkyzpWNjJ5NqL6PjJJ7g42rQQ3Eazu8WBxhfBYh71Y8yR0X?= =?us-ascii?Q?drBBmPHmuQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c3486077-011d-4406-3dcc-08de7bd62de0 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Mar 2026 23:14:55.7429 (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: adTP8lKqTxT8+0Ql235+tguVfujME/RjiPfrMyQx5QaeqjGpErX2Tksxe/RFN3VqR7ul5L2kuuYm+/1pNK8vkQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR12MB8078 On Fri, Mar 06, 2026 at 09:06:08AM -1000, Tejun Heo wrote: > scx_bpf_reenqueue_local() currently only supports the current CPU's local > DSQ and must be called from ops.cpu_release(). This patchset overhauls the > reenqueue infrastructure to support flexible, remote, and user DSQ reenqueue > operations through the new scx_bpf_dsq_reenq() kfunc. > > The patchset: > > - Refactors per-node data structures and DSQ lookup helpers as preparation. > > - Converts the deferred reenqueue mechanism from lockless llist to a > spinlock-protected regular list to support more complex list operations. > > - Introduces scx_bpf_dsq_reenq() which can target any local DSQ including > remote CPUs via SCX_DSQ_LOCAL_ON | cpu, and user-defined DSQs. > > - Adds per-CPU data to DSQs and cursor-based iteration helpers to support > user DSQ reenqueue with proper multi-rq locking. > > - Adds reenqueue flags plumbing and a lockless fast-path optimization. > > - Simplifies task state handling and adds SCX_TASK_REENQ_REASON flags so BPF > schedulers can distinguish why a task is being reenqueued. > > scx_bpf_reenqueue_local() is reimplemented as a wrapper around > scx_bpf_dsq_reenq(SCX_DSQ_LOCAL, 0) and may be deprecated in the future. This is really useful! Small issue on patch 10/15 (that you've already fixed). Everything else looks good to me. Reviewed-by: Andrea Righi Thanks. -Andrea