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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?mAn3zHnEhhLfomY2PSxK1Ngy604vSVFptY9lGlOlFaLJMA2ZJfgGtzuyNXQ9?= =?us-ascii?Q?YtI+hlCa/tjfnV386cm/WwsuxXpwES3ht5Qjhv45+S6vz8Itky4fNts4Sa6s?= =?us-ascii?Q?gVSE0sr363NDPrE9sy5k67jKqTOAjyAAD8CChVASjcmPvga73KHH1pWwcFt/?= =?us-ascii?Q?rY58P6fnRkDFfEJdF5Jpb2dXgkd9FlE+ELVHOp5E1afsKeg1MpdnUN654q0+?= =?us-ascii?Q?IDenmMULnDDYA/eRDD9rgb1Xv9xD1nNY8kLmiyXj4JT+w+xY6DM7noidxjzJ?= =?us-ascii?Q?95+wGpWNyAjuXgDlmx99r4fVa9DuVDsYp25ky2VmAJxekhWXo70rp6dYHmt7?= =?us-ascii?Q?FlCsiQMo4Fa7Bs1d2oWmp8ys4+Vq6u9DajoXtUkoXqcOV8o8rSt12KnxSJ40?= =?us-ascii?Q?wVU/rx6rAAKj9otm2Gl4+RSYJQfrvjAAjAtTpR4HTa5tbKzScOK89p++i7Mo?= =?us-ascii?Q?QqhNJK0MQ7jRrXNBqxiqV/ycCDMKW1johE/wlYQ7kWuOKVJ8IiKLZwquW0YH?= =?us-ascii?Q?gOUvaVtSqSaYCDTc2oABdXm5x83dGaDyNURwKYqlqu9SqAsyWvumet7aqWjF?= =?us-ascii?Q?1u1Q3pt+xxONujYeMfET7o6pGdiDp87zXeQMFii6flEKxlHMKF7WVdPjvU7a?= =?us-ascii?Q?S8Zy/D1yQE5Wce13W7OIx7SAL0ji4hWsjfOw2a7iTLXMzDe3VM80QehyVp4k?= =?us-ascii?Q?gG0LGJxwvz2EEc0dhk5o5IVm5LwbLw5dQ35Tx2HRHfcMJRHAoRa7wWy4myap?= =?us-ascii?Q?xGs1bZbesWiWd24U1AlbK6uNEyfvoUN0Xpwm2Xmhl4/Kn6TCP2oI52+Axrgs?= =?us-ascii?Q?D9x4cP2dvD8C8+dt9/IdeMJ7Rr59I3hf8KF/mXA3xi10H5CPDzTlAa4JO9fu?= =?us-ascii?Q?eOrHGaz1g+1Mn5c25oS98Ye9GMH2hhKvdNhanaY9f3HulBfdKOQg4tQy0VGz?= =?us-ascii?Q?MFTVj6GeOd4I+Q7RoLcCn3mBmgUjLDvOvj6tV8+KwihOCTQraReMVsObzNzt?= =?us-ascii?Q?2+efGx/04aHPb+6fa76iYO3g5OdLZztuGD2EMExlw2bBu3kGCVWQKh4tXxjG?= =?us-ascii?Q?KfB3MvLYgv80wnHOFu5C8rwogUWHzmjup70iZPY7AILBlMQZ59zXExTr9Kpv?= =?us-ascii?Q?R4wa4Oo9SLxw2qQFkRXsHEFJbXtqM8Li1hmGIdpBwaCYa9QlXkxzDdjmJclR?= =?us-ascii?Q?9LgUzkYh4Gn5i0gjsfQKTgGF/kFhzS60T34n4GIVpUMSPbHyDrvmYZrrPNT5?= =?us-ascii?Q?gOgCdHhD016fWTrpRoaKEFp4mte9mid/h+Fd5FqpxhHxPJ1CM8gE22pk9TYa?= =?us-ascii?Q?dGShMyxPIgCM5PnokQuxpRjHe1j5XNSiY/snriKQH0EN/bJJ01zPsW3rz2zz?= =?us-ascii?Q?za0u+rPLDZqdSGHGUnp1mkk25k3mw8cyPpZmsHXXvsto85ZlOmFBYFyHkx7R?= =?us-ascii?Q?5fFucC8SsQCkncV2dL9K9BSy8MMXgBVPn3tdzjUw08/6mxLiTG0JExSzuM11?= =?us-ascii?Q?SaPGPhX8GRz02QLIugkxf3P0z4FzlrwgA7Hpr7Bp1Qlhouif/br2fTU3+NuT?= =?us-ascii?Q?xIp2JFL8l1EpvavpDJh0EKln3OMmDeMNeUdpLkk6?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 0b00a96a-ee7d-4d52-38d2-08ddfad19c6f X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Sep 2025 18:47:13.7237 (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: nnTz8T4Ci4mu+QGAq6sHR9RvD6No3IGTBCuo2Qh7VrKsNWbO0hL9EY2ax7NT8tV9waO2DPBcLXWLvp/MgyelyA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR12MB7632 On Tue, Sep 23, 2025 at 05:59:47AM -1000, Tejun Heo wrote: > On Tue, Sep 23, 2025 at 09:18:33AM +0200, Andrea Righi wrote: > > 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? > > rhashtable_lookup() already has that as it uses rcu_dereference_check() > internally. Oh that's right, I see it now. Then looks good. Acked-by: Andrea Righi -Andrea