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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?u3WsJQgEGdUL0ONP7ptYVpqfSvbfY6ZV2pe+5RKpZ3yYgvQ4eIbr/o0Z72iB?= =?us-ascii?Q?TuGt/ynUr+S7xPWYxS9BThRIvjeu+uji9w0+70/CZxMY61GZbnacNnK8CfSo?= =?us-ascii?Q?QwhIFLDWjVoeTA4+MuqOUJYCjIXthvQJ/viCk9KcDSNOFhBr1wxOiyRZaLl6?= =?us-ascii?Q?4gj3k+N8cQ/uA6CuSTo7rVymyLn18ksfUrMXFb1Q8HngrsUp2y+EGl9kh48U?= =?us-ascii?Q?2ZpO5hkZGfWMAgQDU6na/gEQwsftNeWM5b0t9XTkdeSyHBXQZ33cVkRjpryF?= =?us-ascii?Q?sOdA2yKdG/HzEDG6dNruA65m/noHYTc+h94KMCjPrNNatKEic/0qHZ3ZcJfQ?= =?us-ascii?Q?oEzm+xUPASH5ZE/L92awCFY2vUSIyMgWRqkj64a6hm8hDF1tY/z3Mx19EcWd?= =?us-ascii?Q?I78KJmhq/AJxVKd433FL8NyasOV6xHZMII/pVAVvM9rYMThs2mqaLr2JaXH3?= =?us-ascii?Q?bfW8F0HGuilUdl2Jv/wIRdrt9OBQsbOma0sJ6F9EhRSS8V5qAPgYXZd4q6Xc?= =?us-ascii?Q?YkiLo0W72TZTAjt64pRxuge1e8ZWzmDpHPBaIPn9ymrq6x0Laa0H4HsCCJ9B?= =?us-ascii?Q?WH12i91lK2jC56D6rxXONuxE34LLBP49L5neq94oeBERuIwXqgzD0v1AG/Ya?= =?us-ascii?Q?ABw5UQmJ4Dgx4zy8HfxoiiqzkhurpRKY24JJ7AL/Zq4dnVOAMl+oiLFdalKq?= =?us-ascii?Q?I/MGA+5obajllllqUxnHQTtMSsI/RgC/aEjtwwAZsB9nH+LooIkPRV6RpTS+?= =?us-ascii?Q?f58LP5bW9SGxKS+kVkpE5Kke/uz6t/V8zxnLZ06C9r43ItBy+0UYOSV612yZ?= =?us-ascii?Q?SQ5i66RnJTW3zB3HNQD+n6+g1WfrZUIRJNh2gjyr3cIhdg5RqLLB4GG7u7EE?= =?us-ascii?Q?JrA2sZS6H7FBO4RjsgCVt4uyJ+iE44tXk+fA29I3GZflKAJsFX4lJdl8h/Bn?= =?us-ascii?Q?z/NQmhxqUPH40nJZIcLbnuWgZ3vXR2PmVnQ7hOEc7wR6glcXVBT4i8NuJER/?= =?us-ascii?Q?H4SMfpFd5FMHS0DKRbzlNCbmHkJcxWltcecZFfB2LL0BJC65HR0lpechdY5q?= =?us-ascii?Q?QT8+dncva7+wY6gMinOmXoYTvZlILL/xUw+0ysTXD8f+OywH7hvflD8Ge6S2?= =?us-ascii?Q?NO5bavvYeMJR27bp3ykycP1orekJbShvKPQRd9jV6QdNZntLEsOhYCirivy2?= =?us-ascii?Q?xNG7bLIDWqvO/EkegLMu0mRbAMNi1YgO3MV7KuZKXNRvX6Z7kelRHqUsUEDu?= =?us-ascii?Q?SbMAVjPGop2+PZ0Isk44+VeRLKwtSM2/QdvcSQDiJorohaPhXcgKEyCWXjWW?= =?us-ascii?Q?6HhzD5/cWzo0eOwuP/GSUqhq6WwVvSvD+D8977Ci4Odxnd98ozCz6uBU+NYl?= =?us-ascii?Q?rLFDFkGQbAOrmGVb3oobVi2jWRadh5IgaHBY3KCuJvG95w/tiRRAh1xjvvqe?= =?us-ascii?Q?nnLtwWsAbOxHhPTIcvnikKoHM5fGOeQXvY6oFeTAdI6GF1Ps5nM5pUH0ZFzJ?= =?us-ascii?Q?5uk5yQBsTTnaRctVNtKPLQrTR28hOlyHtiQCNdeHiumAdNFKKFIICH/vSZP5?= =?us-ascii?Q?Gil/wYkTlfGD/KhTe7dxSJafSVuecdEvm6NDodJMvR3zkHsW6dxZ0IYuPtSu?= =?us-ascii?Q?WMtOU5Fnfn2P4qbGFJX9+gf5WFCdCFv8iYd9mi6gFjrtpVsVqptUUXlBfaFq?= =?us-ascii?Q?gGLYA58hKnJ+aOKus3nfkeDzhuZhzrf1FhbHbmNmr5gdx2sC9WvKAjS2TEoQ?= =?us-ascii?Q?oyE/9g29lQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 8b5c6371-d439-4170-bc88-08dea99d6a5a X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 May 2026 05:24:29.3729 (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: JzOAin6SSU8Y43CVfPf6O4Odmb8qPycPLpWCYVEFK5DBF0XZONgp7IOLTrLwvwli39gcugpGcm1DZy+j+Tb1XQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CYYPR12MB8871 On Mon, May 04, 2026 at 07:17:16AM +0200, Andrea Righi wrote: > Hi Zqiang, > > On Thu, Apr 30, 2026 at 04:45:43PM +0800, Zqiang wrote: > > The sysrq_handle_sched_ext_reset() callback has already been > > executed in the rcu read critical section within __handle_sysrq(), > > this commit therefore remove redundant rcu_read_lock/unlock() in > > the sysrq_handle_sched_ext_reset(). Actually, minor nits in the commit message: 1) s/has already been executed/is executed/ 2) s/remove/removes/ Or maybe rephrase as following? sysrq_handle_sched_ext_reset() is called from __handle_sysrq(), which already holds rcu_read_lock() while invoking the sysrq handler. Remove the redundant rcu_read_lock/unlock() pair. Thanks, -Andrea > > > > Signed-off-by: Zqiang > > Looks good to me. > > Reviewed-by: Andrea Righi > > Thanks, > -Andrea > > > --- > > kernel/sched/ext.c | 2 -- > > 1 file changed, 2 deletions(-) > > > > diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c > > index 45a2668284bc..0f3e9d088151 100644 > > --- a/kernel/sched/ext.c > > +++ b/kernel/sched/ext.c > > @@ -7953,13 +7953,11 @@ static void sysrq_handle_sched_ext_reset(u8 key) > > { > > struct scx_sched *sch; > > > > - rcu_read_lock(); > > sch = rcu_dereference(scx_root); > > if (likely(sch)) > > scx_disable(sch, SCX_EXIT_SYSRQ); > > else > > pr_info("sched_ext: BPF schedulers not loaded\n"); > > - rcu_read_unlock(); > > } > > > > static const struct sysrq_key_op sysrq_sched_ext_reset_op = { > > -- > > 2.17.1 > >