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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?R2Avpxd0AAUnFGHxorDf0r1fpK0AfAceQ5b6mVxMK9l3Gvean8Vj9Q4cMp+5?= =?us-ascii?Q?nMV6zFiT6UxNp2awRo0+S9SRftFs8WVpvN5lBZo69uUCd0r/N8DKfwIO+G3w?= =?us-ascii?Q?qPWjd+fuK8pk3Z/K2VHCtTdFh4Em38YdDZwQ2/IsrKno7UTp5vXfgEV34l7T?= =?us-ascii?Q?/cCreL9bahkglAlI6JurYe/4nsRyfgeetjgMC21g7H83KO5fKAFd63getpcK?= =?us-ascii?Q?atJjtOpq5+7imKIKTYSeanWqFRgyQijszJ6NuNDL9jMCxofKtUqoYUwS5g4B?= =?us-ascii?Q?9qFZd1gkJmFSewId0Ahtnkfm+sUVlwx0/wgFS8lGHV/3HHGEmnnQph8ysFhy?= =?us-ascii?Q?bsjb/Du1jJK2YvU/nKjt0kMXQIW5Sqdwn7VszjZFuiQ20f8FublSQnISCbDP?= =?us-ascii?Q?a/PzyysrkbLZKsaa8XgBJfrdLPy+MHmztXb1slc04dZ7kfHlewfsLA0XNQz0?= =?us-ascii?Q?7YWow+4xSHd81FpH6r6jxibR3Uuc3oTFW5FhnBFA/Re4YUR3u+3v2bak1ugX?= =?us-ascii?Q?q5p9VeEbItJV/LBFP1s8SiV1doxnlyLvmAXHyNIMVZkRWlCI/GgoigMYCoRN?= =?us-ascii?Q?sNCYoYPSVi0W5836T/glxtw37KGnpHolG2cGQqGsO8KcC5zscp60vwXxD7gz?= =?us-ascii?Q?0DQT/SPb4l2yRkGYIAbmLVVb6jOFJvpZ9LfNiMTS+0/Xw+QNbckhDdL/fSYL?= =?us-ascii?Q?y2ohxEOZfCu5fWTj5KTdjdQyIGagkLlEI2t8TfGAlK/Gz4ttHGAz3vVEZ9Xc?= =?us-ascii?Q?YOSJbnKeMTVptEhVIwyf3bygh8OrKT0Cmn8ExPso898L6x4tYXFfHysbt/NM?= =?us-ascii?Q?Oxp1YlBANSHAbdbg/6mCwSTwURCwVOj9p9Upr0b/oLg2amrM8T94jCxKvNoo?= =?us-ascii?Q?f9/HV+EtAJE/BJJJk+ytww/23KHsxaP/QKc4Mc45Hl5oGyHm5WFMCOFJiljJ?= =?us-ascii?Q?D8/cMzYzA8ZwjFmJDyAQkMarQAiFSulUMvBeftN06K/f7MrClbHtCRHnt0xn?= =?us-ascii?Q?A5eHyDrWZdbp/s3v54DgCMTkDS9ih3CoANTfp3ETaU0B8RiNisunpx7bZ9ns?= =?us-ascii?Q?ygV9TKaTynR5FIGEskx32dUzpaM7yz54eMiULEH/Cm0xUPwrie9AzZMkkSmC?= =?us-ascii?Q?TDjc9VHIjdql7GCgUZsrnDLMtW9toS1cE32OTWQOToEPQTLfyFi/JzHn/2kb?= =?us-ascii?Q?LA6KttSbQc4AXVAjbWjBaL2nv/zCz8cFFfPkqtipm7lZbGzU8Kzntuvu8DpG?= =?us-ascii?Q?+EzwUDZmteiYMvQRerCAzimCG9/8jSOGpHykKy4c8DCTPxZMwM+Pux3lVLug?= =?us-ascii?Q?/TF9uaMxy/LQXADWJj26Ge7TAuqA+kfGx+VNpgE7ALCCsoMOGqrChEwOQ6Tb?= =?us-ascii?Q?QQfCQSPMWzUlhxOlt5YZab9t9DtwG9zZR5yHt+2PHEwlmRM40rrIwqcFjKKe?= =?us-ascii?Q?RMdpcEcD5ZS9MHR8sL8a2+FgOfl0cqSF2XSYT2FpTSKYS/6xMAy1qDdNnVH4?= =?us-ascii?Q?KM7V3oO8EGtKArGM486wrgVpqSn9Rth+IV44SjuDRJpX5U77dlkewNBY9cnS?= =?us-ascii?Q?QIYktFPgmr0db/4zMOZ8katqFr1OTzduxGmzKkE/JZz+VEsZJsBi7JC6vlII?= =?us-ascii?Q?te3kZpd3JqxlIVfA0+YtBdLpsw/t11GMBbFJ6eQN6X1/Ns0U+DM9kNkCQ/wV?= =?us-ascii?Q?qHZrgOPTDrunGLkfp+MdTItXD3mJWC0gO2WfxaYsIe4XHk1ypKE8VydXHzDq?= =?us-ascii?Q?rPXBviVJjg=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 7ff26acd-5e96-4034-d686-08de418832e0 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Dec 2025 18:30:35.9808 (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: WVdTMxTbkNDnorXRk3+vAAjJxthN7w71jmI79C6u0EzpiqCCdA7nFisGecwuxyE9fM1z2KoSdM35LpGqgYeXTA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY8PR12MB8244 On Mon, Dec 22, 2025 at 07:53:18PM +0800, Zqiang wrote: > This commit only make irq_work_queue() to be called when the > llist_add() returns true. Just to be more clear, we could rephrase the commit message as follows: llist_add() returns true only when adding to an empty list, which indicates that no IRQ work is currently queued or running. Therefore, we only need to call irq_work_queue() when llist_add() returns true, to avoid unnecessarily re-queueing IRQ work that is already pending or executing. > > Signed-off-by: Zqiang But overall, looks good to me. Reviewed-by: Andrea Righi Thanks, -Andrea > --- > kernel/sched/ext.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c > index 8f6d8d7f895c..136b01950a62 100644 > --- a/kernel/sched/ext.c > +++ b/kernel/sched/ext.c > @@ -3439,8 +3439,8 @@ static void destroy_dsq(struct scx_sched *sch, u64 dsq_id) > * operations inside scheduler locks. > */ > dsq->id = SCX_DSQ_INVALID; > - llist_add(&dsq->free_node, &dsqs_to_free); > - irq_work_queue(&free_dsq_irq_work); > + if (llist_add(&dsq->free_node, &dsqs_to_free)) > + irq_work_queue(&free_dsq_irq_work); > > out_unlock_dsq: > raw_spin_unlock_irqrestore(&dsq->lock, flags); > -- > 2.17.1 >