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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?2iB8hMbwdWf+tbXTQY5mfleEj+qThIeSehtUVHIK4DVenNvwqB9QqmVFJtT8?= =?us-ascii?Q?7ayLwqnDVrVf+O6m2nBPEp0cC2fnB88+JQWT11sKBe0b5FTvW3SbfC17h2Ha?= =?us-ascii?Q?RCs39kANINmfGmd8ptCsiRs6jEAcKWorJVZdRswxxjFKRQyea5BFfHJ+w2My?= =?us-ascii?Q?sxJvW42Ow6rhMOSpjOGR6Dm2UaJsBeSXqiA4Si43NftMx1/iJocZ/t5NL5z+?= =?us-ascii?Q?VRBI4y7WldlvV7HTzf+Z3yLTOfhoIsqd4NGVg3kjwY/XXaX+2KhzF4aqtzQj?= =?us-ascii?Q?BfyQWn5ijT/HtZonOSABOdWY2v/vaCYYq6h3D0y4Pzm862eYA+Ml4ZFvguDx?= =?us-ascii?Q?yBlRie0B39RzCDZYEt6yrWWp6As24WnCdL1Go9jIcQ4hqyRWhZbGmopUNm2m?= =?us-ascii?Q?RQBBXhVz7+uYNY7+vwgGuYBd3f1l7HnSkemQEpnJ6kCsyPKeefRE/n6mx/4L?= =?us-ascii?Q?eDzhLbofpfcr4PM4KM5B65P1iJD/bFIn7sx7KjBoSTfSAQeL7/Az2ALnmIxe?= =?us-ascii?Q?EIEJ3SEzfyI/0IWTJ+Xvx0NgoM5S1Ao9WYch6xxrnxIshXdFWestA6srB0C2?= =?us-ascii?Q?ZEvUns2vB7KX+CRt1mUpRtVAUOB18R7Jf80tUKXb6ewsixiG+g7VDHVRQvEq?= =?us-ascii?Q?lk2GpIzHFUQDxn2yQLuO6WbiIwtEEuip/gzdfQCtq7k1zpGSrDOml2oz/URY?= =?us-ascii?Q?k92TefLtjV92CfW7pQZqDlBVw/lymtexxVS7MAQOz5UOTIRP1fExyxaKNI/X?= =?us-ascii?Q?Rt7cWAh89dFISwU21plSqEtmvyCONMF+IjK1Nmn/T5bxJpARDdeFq7CXyOXd?= =?us-ascii?Q?fAsQdELUWEHsSOMrklZ4fQ+a6DnhWiOb9nW0HKW5QI1fB3/2eXFpTpm1w4e6?= =?us-ascii?Q?Dz1t8vXjSr2BIodA8vRxscTUf7j+a9qDwGMtPq+gneGFebTHcYHPtPw/E59M?= =?us-ascii?Q?GJuiJEDA2DkD0OCaOA+dRLtR2QuxK0/HQ37G6jwN4YENhD+irWH04a7OvTK1?= =?us-ascii?Q?6KH8E/vZ63aR359f2hUJbdHyT566tON/VQGG9CPvCcfwVzg6MSSxlSKhGr7g?= =?us-ascii?Q?fhmY5XYYfRqwV3AFkJCNOcBDgxFYj82pjUT1jI76Zz9YF0+ssGPH/bUsBOqO?= =?us-ascii?Q?ljhup8ZCWFhwvd7F4GB63wmR6ZWdVmyLd6h11lzI1HuXAd9OyWNJcTDDkYLm?= =?us-ascii?Q?u+WC93vtX7qYhDShgBL2tNmmiAuHYZ92pFvRLxo9pZqRnmXRykWYy6OZ/P/M?= =?us-ascii?Q?ocAE5xDOkH3o206KPfGxPSgyMV1hIPr8n/pu7leznE6BEfxdIzkCoJPRV5uK?= =?us-ascii?Q?qPMcEA7IL5Yi/QOA+WzuFvN6SboVZzF94EvRuWr/KoI1tKcr5uOTnCZRZt5v?= =?us-ascii?Q?Z5JdQKT9psB04oEQ/8htsLs2zilevPh6eR10s4x6zuy91xb6+I0QKBA9a7si?= =?us-ascii?Q?CLuai2P63O3U1/qbneboZHkHGvcqFsxY/s1VqjjANuTa/ylPNsXyLIRrV7mC?= =?us-ascii?Q?T0djlzQSOwVdDIn/8WljTx0BoArRwzaE8fxiCiHuEOm8D2hPB7kVAwxPaECu?= =?us-ascii?Q?ai4ShD0PGEGNvwmkXGasdhaVryWAMODTSYPdxWdB?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 691081e1-0ff1-4a44-074f-08de2211de69 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 Nov 2025 17:35:27.6795 (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: aBE6sxxdqsJFlHIqpIaJNTh/y1kP3FHsbDagzY1pJy33K6R8H25Hqw2QYS97bS/c94/i4LImc0bHS4cz0oRTLA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS4PR12MB9633 On Fri, Nov 07, 2025 at 07:51:49AM +0100, Juri Lelli wrote: > On 06/11/25 17:39, Andrea Righi wrote: > > On Thu, Nov 06, 2025 at 08:13:39AM +0100, Juri Lelli wrote: > > ... > > > > > @@ -376,8 +378,11 @@ static ssize_t sched_fair_server_write(struct file *filp, const char __user *ubu > > > > return -EINVAL; > > > > } > > > > > > > > - update_rq_clock(rq); > > > > - dl_server_stop(&rq->fair_server); > > > > + is_active = dl_server_active(&rq->fair_server); > > > > + if (is_active) { > > > > + update_rq_clock(rq); > > > > + dl_server_stop(&rq->fair_server); > > > > + } > > > > > > > > retval = dl_server_apply_params(&rq->fair_server, runtime, period, 0); > > > > > > > > @@ -385,7 +390,7 @@ static ssize_t sched_fair_server_write(struct file *filp, const char __user *ubu > > > > printk_deferred("Fair server disabled in CPU %d, system may crash due to starvation.\n", > > > > cpu_of(rq)); > > > > > > > > - if (rq->cfs.h_nr_queued) > > > > + if (is_active) > > > > dl_server_start(&rq->fair_server); > > > > > > Something that I noticed while reviewing this series is that we still > > > start back a server even if the user put its runtime to zero (disabling > > > it) and I don't think we want to do that. It's not of course related to > > > this change or this series per-se, but something we probably want to fix > > > independently. > > > > Should we just call dl_server_remove_params() when runtime is zero? > > Looking again at it I actually wonder if wouldn't it be better to use > dl_server_apply_params(dl_se, 0, dl_se->dl_period, false) in both cases. > dl_rq_change_utilization() deals with dl_non_contending (inactive_timer > armed) case already (even though sub-optimally, but we can fix/change it > later), so we can probably remove the special handling you do in > dl_server_remove_params(). The WARN_ON_ONCE(on_dl_rq()) could be moved > to dl_server_apply_params() as well. > > What do you think? As you said, it's probably sub-optimal, but I think it's still better than missing scx dl_server entirely. :) I'll give this approach a try and check if everything works as expected. Thanks (and sorry for the late response)! -Andrea