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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?i+BM+K8E0+wfY2sBa93fDYkx107Yct8cmg5gVD4nU31Qp7qBMhmZ3UnLMAAC?= =?us-ascii?Q?O7KwEnh9qJZSSDT9jREEPsDmgL2eWgvYBW7TM4/uY5AZLtpCocvLSURrXmRh?= =?us-ascii?Q?AiDEGwX4QuUnCKUT3lrRuYFGSAjH5SB51S0eoIAByXxlsQPK1u+b3dS8CVdY?= =?us-ascii?Q?/LtMH6t8yrPzlWs6r+PQS9a0SDb/+/DSIjpX4Ps9NtgGQnHmXwAGe32bulB0?= =?us-ascii?Q?Me6W8coddZwDo67+iEGqrdJM0enz6DCutk/1ZrCv8PWj8UT0b53gLCAzBOtv?= =?us-ascii?Q?97AsbXPDxukf/NEWoT1WiB0BXru8rN5u6jx7o8JV8Qz45oexii4VmMkDTjpa?= =?us-ascii?Q?KMIDijx57neTx1aXZVDNQRc0lCvkIOTEhCPxXbHlc+mJRqHojCTOOhO73Bls?= =?us-ascii?Q?25z9D8qyqKOC/51U3kCH7LPcYQDBmRsfFV4cXEjWe4XZqI4+l7D3VdHMrEJy?= =?us-ascii?Q?uAg1mPLW1yyefL/VhnFIBz/iPkJw9Nh3SZAMsMK57PAPTO2eF5yBVpQ4w9PD?= =?us-ascii?Q?udqyIGwkzsV8mYfGTjaL28AbM7nQzOq8ja4tq0NZdbBPf0khKBboArmC80zR?= =?us-ascii?Q?1FVMgmgHoQgddJC6D2DTpTNXWC+xQ/99yizjVf0Q80RTAPNuNrZF9j/i/pTN?= =?us-ascii?Q?tRxnCZBOi/qf7COUFK7Nuayc0Bgg+9hReAQ+p/s+CSMQVH/PJQlgWDfSeWJL?= =?us-ascii?Q?ePcIv+C5PHzthS5E1A+XQs9wH3bnpcjJLn8HOh8VzonyEXiir/Xxw07CPE5d?= =?us-ascii?Q?mH36EX/WBV/5bKmXlQnMNbFGlFwhyOKRE81RlxiDpUISfz+ALUsjZ/szbyIB?= =?us-ascii?Q?Sh8QasMZBmeNju6ynAcEscmvJlZSxgqbnLIB0Xt3bN8Jao9KKgjxPzQ9B8y3?= =?us-ascii?Q?qchQFX1GaBblD/gTbfG5lsJr0Pbo4KFUO4IMdnO+/j6B+cabEoGu/2NV9850?= =?us-ascii?Q?Wc9byriuX4FlefCZfjYVcq2JsvzBf24TFf/gPfvxX1/iBwUGu3ocDTPxMsu1?= =?us-ascii?Q?Whwch0OUlXhUzSwXrVoKj1Y22hwNqbRLWduMtw84LfktY2Zf5kL8neixhKKO?= =?us-ascii?Q?BqpqYNNt4pktSkgnNWv21+6RjxOEAVaESmEzjj9MjCCEcdDxNiiMWM3vBQqQ?= =?us-ascii?Q?Qmft8RWczCcYnjOsS44kZDNGqpieLJMJRr07zN2pcWwOzQTWcXxjYd+bgvN4?= =?us-ascii?Q?qKLjyt9wr8QfSlEXJ977t2eOXkviw+xXkke+AL2dR9HShStur7XKxPtVSiNg?= =?us-ascii?Q?nBx64JCP+rNXd+D+i+eSXer9ePAmhaiOOX606vjmdIbn3QQNzoh9VdTfnqfs?= =?us-ascii?Q?ltsQGj+hYuZTEvKsqzw1DJQ9ukBt9GDIRRT96gP/K9R9XN/3mAnW3cmWKUcJ?= =?us-ascii?Q?AptRPUT6Dm4JplKrH3uOOpN+DDm3hdwMMjvLQLt649VMzzVmDcUfU3oM79E4?= =?us-ascii?Q?jfH+hqvnYOanwY4W43QAORLPqG87rQYfTjBr0IFSIXWIj+JCcrkY8Rx3HC5F?= =?us-ascii?Q?bVDlEqEKmg/apnpM1Mr+NMz0GGrl9Lwev6vraiqE1NNoJMc1uH5Gu3jil0Db?= =?us-ascii?Q?WdcwlrL/+EnFkTwiGqFQZ1yWnIp2qsU7udusQ7jJ?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: ae6aa02c-1c26-4a9f-0887-08ddeafae258 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Sep 2025 15:02:21.8960 (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: x1e03+NGdTVWXR5CamryByCrQiTUcgKhfuxt6vwkLkXBvsajJxWLEkRwYoQkCWhN2oF6iD2Stfr9Z3cqepV5zA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB8953 On Wed, Sep 03, 2025 at 04:43:19PM +0200, Juri Lelli wrote: > Hi, > > On 03/09/25 11:33, Andrea Righi wrote: > > From: Joel Fernandes > > > > Currently the DL server interface for applying parameters checks > > CFS-internals to identify if the server is active. This is error-prone > > and makes it difficult when adding new servers in the future. > > > > Fix it, by using dl_server_active() which is also used by the DL server > > code to determine if the DL server was started. > > > > Acked-by: Tejun Heo > > Reviewed-by: Andrea Righi > > Signed-off-by: Joel Fernandes > > --- > > kernel/sched/debug.c | 7 +++++-- > > 1 file changed, 5 insertions(+), 2 deletions(-) > > > > diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c > > index dbe2aee8628ce..e71f6618c1a6a 100644 > > --- a/kernel/sched/debug.c > > +++ b/kernel/sched/debug.c > > @@ -354,6 +354,8 @@ static ssize_t sched_fair_server_write(struct file *filp, const char __user *ubu > > return err; > > > > scoped_guard (rq_lock_irqsave, rq) { > > + bool is_active; > > + > > runtime = rq->fair_server.dl_runtime; > > period = rq->fair_server.dl_period; > > > > @@ -376,7 +378,8 @@ static ssize_t sched_fair_server_write(struct file *filp, const char __user *ubu > > return -EINVAL; > > } > > > > - if (rq->cfs.h_nr_queued) { > > + is_active = dl_server_active(&rq->fair_server); > > + if (is_active) { > > update_rq_clock(rq); > > dl_server_stop(&rq->fair_server); > > } > > I believe this chunk will unfortunately conflict with bb4700adc3ab > ("sched/deadline: Always stop dl-server before changing parameters"), > but it should be an easy fix. :) Right, I also tested that in a separate branch, this patchset is rebased on top of Tejun's branch that doesn't have bb4700adc3ab yet. But from a sched_ext perspective everything seems to work fine either way. Thanks, -Andrea