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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?FEwFj7Rve5tlvQyycBo9ZPtSVAJ8jR+lb9OahUs9HODGlq3yyy/0dFYa/bS5?= =?us-ascii?Q?qcXotEIFRWeU/TXFbM7sW5v1FGbCWCsbpo9KmSA5AK/p9R47cvv3jukqVr40?= =?us-ascii?Q?SB3WWdAtfmPlcOuaRhc2E44rzDj+IJSnVSlvNm1UcRpqsoFZHsM6ULl/E0cN?= =?us-ascii?Q?NLTDpBFLuYlo38ML+eFq4n+0NatUaz8KpVGORhS/6L57EOAamQQBwDDQw8hR?= =?us-ascii?Q?mz3DJ8ggluU5tQONCRBOBssgvQoL35aTYFuFFDtpSzO+k22VI4VUIWmOHLXA?= =?us-ascii?Q?V0ICN5Ddb6HoJm6m2okA8erBRneCGBgsyz2rS4mnt3ys4mPh+L7CJbqHf18e?= =?us-ascii?Q?vA53TVGoSV1r0qHaxT6yJbv0hbrDXhevpc6R3p87Kcs+/tKKNlD6yEBiLODP?= =?us-ascii?Q?u9GQFiTosKZJuUxRTgwr2qRxrrkYS1vJO2R+lg/wY2UCDBQafnJxnTUNWwLC?= =?us-ascii?Q?LaheVHb1AapVli189udIPiIDVN5IC6dBL82u0WykZz35U6QnORfvjTmQ277x?= =?us-ascii?Q?eKpuGdd68g/rGrN6aPvfxVtSAJE9PqQJjYXhtctfT+hX0icFS4UcNB0uM77N?= =?us-ascii?Q?xfZtUt4B0Jut1vyx61bFzkrFJd4Q1KVT+hGh4U6bGjbQcoE2ZeHtWRIW+UlW?= =?us-ascii?Q?J++rse70gixen6+JgKNMJbnSvJvYWqLRHCrg26CD1VgxNCN9pesAeP+GEZKx?= =?us-ascii?Q?ks6WS4eVUTKoujz0Dh3br6cS2wzhbsVHwXSmNVxvqfBIqOt3ZbO5UOFSKRNF?= =?us-ascii?Q?YfNVcX2WooPbtkEC07npBitGudlF1VWwTmz7OdRKmq6a9EQdz/x3pB2rCr0c?= =?us-ascii?Q?QNyTWh8McsE8MAmrzOi0SnKKCaswZNl292Mq0pIqvEfjhzxoXmN+0zgKhR1b?= =?us-ascii?Q?kQc6l0mT2aQVrNS5nqaw/JkbBEZaYfc0bjIN/qo/tJDIDSoO/et1zoaFozvi?= =?us-ascii?Q?CxYSoJhF04qzRar8GSnB5J0lp8jii/0nDaYrGTi57upqwYgS9ANAk2su2rC3?= =?us-ascii?Q?UpGwWKKlIhXa0GOdT3xi31VwupuXFaVTuaHBFkl+ev5S4uBgScw46VbDqCRK?= =?us-ascii?Q?PMlHuC0+PC0tp7/kd0xh0n85lsGS89610rPGjoHOPDWBPfoZkcHoco1vqJmO?= =?us-ascii?Q?6zXGFdeqouBqdxhJAefaf7AUbLxizX6Q6mDiks9/o2NrNHYgmGkcsSbSftBi?= =?us-ascii?Q?CfNmAVZdNUsPxeJXC5LknmppueFkKC1s0W8SyFTBnwBc2qj0Bc8K66lyAHvF?= =?us-ascii?Q?KVmGxrkY1eTBkCG4jL2k4dBzvuqs12w/pbHxDyfIoT2AHNxbaWhvVIOcEHf+?= =?us-ascii?Q?ojHD+TIhguVL44mVlEAZoWR6KJqHGvSO6WO8QD0bSdxmhJ4TMgHETozPdP6I?= =?us-ascii?Q?1ngLzLn5nDp/3MSJs9GY4qF6IdbNJmDbE0ENa0SMp1rfdaIdrVU1T2OAC/c+?= =?us-ascii?Q?ZR7ZbfOqhCumrGepDRM6Oeo1uRbZO3Naur1vO1SY2i2r9STNwAMZT3jNmsU2?= =?us-ascii?Q?4pBZY7e914N0zt/25AyPQVojVi7zb76CR4J/bTN+FxQnBTxb7c6OLd5hNguz?= =?us-ascii?Q?A9SjSfa4OZ6wLIVLXtjNtercG8vpU7empGIfHoGL?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2a095419-32e5-480c-4eaa-08ddfa716b1f X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Sep 2025 07:18:39.4398 (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: PMFCN9USaoK49NGcyh5WaAKoTsDohMsf3GPRUuRRuoArHGMb1RulozVsmJBckDoe0MFcePyPJgBAp2vOpe/6BQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CYYPR12MB8940 Hi Tejun, On Sun, Sep 21, 2025 at 03:32:40PM -1000, Tejun Heo wrote: > The find_user_dsq() function is called from contexts that are already > under RCU read lock protection. Switch from rhashtable_lookup_fast() to > rhashtable_lookup() to avoid redundant RCU locking. > > Signed-off-by: Tejun Heo > --- > kernel/sched/ext.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c > index f5873f8ed669..df433f6fab4b 100644 > --- a/kernel/sched/ext.c > +++ b/kernel/sched/ext.c > @@ -207,7 +207,7 @@ static struct scx_dispatch_q *find_global_dsq(struct task_struct *p) > > static struct scx_dispatch_q *find_user_dsq(struct scx_sched *sch, u64 dsq_id) > { Maybe we should add a WARN_ON_ONCE(!rcu_read_lock_held()) to make sure the assumption is correct and catch potential non RCU read locked usage in the future? > - return rhashtable_lookup_fast(&sch->dsq_hash, &dsq_id, dsq_hash_params); > + return rhashtable_lookup(&sch->dsq_hash, &dsq_id, dsq_hash_params); > } > > /* Thanks, -Andrea