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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?0AW2Cv0bqMflqx7n/5m42GzHItzTSKKlwbVY6u8oYSSWXj8FNdRc4Zazh5g4?= =?us-ascii?Q?Zl6KtwWbj7E77L1Srhm9CXbKmDDi1BzDlt+8AVmt7HRQZ1LopHmcFjK5RpMr?= =?us-ascii?Q?1HLtKnMTAar+cbmO6nsKgufbq0r8mGTynhw/ATDPe7IWRImf35dr4WVIKRot?= =?us-ascii?Q?GhW08GQR7CuWqBYwxp1EKP4u+GMsceG+i4ELsnRaRKtM5tCmxdhBcbplZsEh?= =?us-ascii?Q?Iitzx+M4/FeAeZ5l7pVQ2WrHKcOz4itar8Kuj9aXlgnndrNdmiVSc5IPdOBR?= =?us-ascii?Q?xf3lRiGWOby3XwDhE0RJlHH818Mtr6GCL+kFlgJKfNeO6f0UNanqtcVIMmA6?= =?us-ascii?Q?dWGADTdeaqmuJkPMTQyG+rawBXm255Bi6sWqiRSp/vphuKDHGF8JXpdx8hZv?= =?us-ascii?Q?DkAIKC3z6UV7GNpGko+F/+8qqIhGfE54IzDELv7IEjtVkRYwcGmQvzLZqwfj?= =?us-ascii?Q?nNCoJBQwO6r7g8Krh/7AgKQnZytDKepb03VBwVMb66L3QfIJ80ZD591Ldot5?= =?us-ascii?Q?7gQlQIbx4mSAJoW9EO55quZqqrGJ7Qbh0Fr28YzfrySeqIdkEsRJwRF5IZ5B?= =?us-ascii?Q?/ZFOQJGgIKwILajQES3axcDlEuFClvUi9VVvitG5pSIE1StOyc68fme+0gjz?= =?us-ascii?Q?x7n2UgXdaMIKLYwgE1O5TIl/V3N+l+cNp7Hg0pX5IOOS1HSh1m4PWnXqtxhX?= =?us-ascii?Q?2jibKjavaatQr4D97lTReiRqXDs5NrchT8AecoPfaeXhW3BRSHBy+7VLERVF?= =?us-ascii?Q?D9isYMf6y0Zy3174s0Ikkk92XK2A28cw2YnH8MUPxhIb3C86fQgyI2eL2T0+?= =?us-ascii?Q?uellMwyt+AlJmDbWvc5LMrZIHUt25DuCBrGxWGmcVHBPOpch2NIbIOHyohOC?= =?us-ascii?Q?Jj0VhaWkKHK5nvKlGBmOeOW5OPsNyoOjIEbuwIfabd8v/Kd74xWpJfe2fyNC?= =?us-ascii?Q?FxRW5O6wv34lyWo/jajkxiBT+MNcGUtEQxK4BlhyvVXEbPKSDuAKEHqt+y29?= =?us-ascii?Q?rS5HLU0UtQMiYe8I+iZ79M0o1c+gJNmaiwE1QUuH6ITnXg+iUU2dBeXHBRli?= =?us-ascii?Q?C9VnSmvS1hIdzS7b3fbzk6WcNmj+C85fuEWqB9miIyzcKJLf/C+MYsdfIj9B?= =?us-ascii?Q?ckwJa+5vHaUs+V6Tjg1x4PTsxW4lk2Rzw0Itrh8sp+BJsmaQSuujRvxd2tqo?= =?us-ascii?Q?Ym15fW8imnArh6MibvLlLvaOBKTqad5n3476YRUGw+Per1tJNlQbgJM9C4c7?= =?us-ascii?Q?/JOWRFYQDozRQoA3U1vu9DCKvlJ1vPrboEE+t22FDxSsj7KosZ80G3VYb4f1?= =?us-ascii?Q?BTfa0001CO4souQnolTBso9r7WsTZ7Uutv3ZlGnUNiGkPahARR4pgJBqY6yR?= =?us-ascii?Q?eLKnSRCvfBbgM2IxiTht6XQwb6PmAeTTJlMGsxPTvQSPN+VMU+FdKoeY0GzR?= =?us-ascii?Q?YEy4j83nzcFh5sQvBk2/ErsXKDxB1ngxBC6a4HVtVTndLS/WO84hrltkfLiV?= =?us-ascii?Q?qsqthVHl72bzoFkAvVGb4DFjHiNmSm0ENDdA82/gKaS7jcp4VIdtM15W/g+c?= =?us-ascii?Q?qSz1HPLusDlwiEDkZ+GmDkO6F3N3esEKggFkZVrD0dRg4hi9xUaq+UhdHyBh?= =?us-ascii?Q?yH4UtGdy0VouBBK/Bh9mvMS+EUR/Lvo2HEqUAF2QhJByU4IMT0ZxtqKcQmex?= =?us-ascii?Q?AWQaSkjBuvac3q8cLzebG0OAKJFw2j4dhIirMuRAMH25y4AWlvrXtZxkyTNr?= =?us-ascii?Q?t3UsbJUACA=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 47f7e2bb-5624-4fe2-800c-08dee7c740d2 X-MS-Exchange-CrossTenant-AuthSource: CH2PR12MB4824.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Jul 2026 08:00:10.7542 (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: vk3YT2Dz9LuqEc42fqgOZK8HhuBe/HYlNskjWf60jYoqWjNj4yGpmMfZTVeOqVDSCp4AsGhpCmuK5hmvfhYhgg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN7PR12MB7323 Hi Tejun, On Tue, Jul 21, 2026 at 12:31:14PM -1000, Tejun Heo wrote: > Hello, > > v2: v1's 0003 only added NULL checks and, as Andrea and sashiko-bot pointed > out, left the cid tables readable while being filled and rewritten in > place. The new 0004 replaces it: each root enable builds a fresh table > set privately and publishes it with RCU once the layout is final. 0003 > is a new trivial dead code removal. 0001-0002 are unchanged. > > v1: https://lore.kernel.org/r/20260720082605.1451945-1-tj@kernel.org > > A few fixes for the sub-scheduler and cid-form code on for-7.3. > > - 0001 attributes a runnable stall to the scheduler that owns the DSQ the > task is stuck on rather than the task's owner, so a bypassing sub's task > parked on an ancestor's bypass DSQ blames the ancestor, not the sub. > > - 0002 skips the default CPU selection while bypassing. The pick is discarded > by the bypass enqueue anyway, and it consults idle masks a scheduler doing > its own idle tracking leaves frozen. > > - 0003 drops the unused scx_cpumask_to_cmask(). > > - 0004 ties the cid tables' lifetimes to the root sched: built privately on > enable, published with RCU once final, unpublished and RCU-freed on > disable. I left a comment about PATCH 4/4 (purely doc stuff), overall looks good to me. For the whole series: Reviewed-by: Andrea Righi Thanks, -Andrea > > Based on sched_ext/for-7.3 (b20dfde5ec54). > > Tejun Heo (4): > sched_ext: Blame the DSQ's owning scheduler for a runnable stall > sched_ext: Skip the default CPU selection while bypassing > sched_ext: Drop unused scx_cpumask_to_cmask() > sched_ext: Build the cid tables privately and publish them with RCU > > Git tree: git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext.git scx-sub-fixes-v2 > > kernel/sched/ext/cid.c | 279 ++++++++++++++++++++++++++------------------ > kernel/sched/ext/cid.h | 58 +++++---- > kernel/sched/ext/ext.c | 80 ++++++++++--- > kernel/sched/ext/internal.h | 5 +- > kernel/sched/ext/sub.c | 42 +++++-- > 5 files changed, 298 insertions(+), 166 deletions(-) > > -- > tejun