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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Dc8a9QNNG/t1Pzdey644wKxWKDZclDyzK8b18+BqdBk4apFDKRS+Ip/JH0eM?= =?us-ascii?Q?7N0tcb+cthu012vZNLJgUgx6RjtZG5Pajz2zJfDVDs3NYUe0WGS/jDaz6O5x?= =?us-ascii?Q?Ds1rKbvdlQ9JSy+u8prVungpGtNqauDDPBl/oUrmauZVjannyqjKV2T6tqMJ?= =?us-ascii?Q?lgItCkz0p52/+7U/oXuVwsGYBN2Aqcf5nf97wmE3ebu1o+tQcau50MwJbnOn?= =?us-ascii?Q?XOP1y+uFXByuzDqorn8H2C8rE8nCMdE6EHMDo6sZRvSc3lgXmIZdCHylWYOb?= =?us-ascii?Q?x4oWx+h6RhMjPT0hGjDpPVSTeEoRINTL3GnTOidGGB8wdGsLyqlsj7YBW0Ch?= =?us-ascii?Q?INYFEoW926j0WZyIn78oymnMCthA4hijefxiKIY0ASevKhtKnrVeRKD0SeVz?= =?us-ascii?Q?s3LSXMms+po/EPg8jeEyc7uv2iz9BtuzyCCJWtbMmf8WOyq0+Be4juFzcrOS?= =?us-ascii?Q?tJo8hYR36hN4wDF5dYhwoJFptM7EUjmyHLCnNMv8VJaFVdb0TIwpiGo7+tQK?= =?us-ascii?Q?hGtUM8aInKMSbEZoKeWZ745v3llLGSL4DvdeebYf96r8Icyn1R92ov0x2oRy?= =?us-ascii?Q?P25M2Ch8Ji0UPMW8HIUNMNmD3Kg7QDhoJZvyAgwpkCltff52Sky6ic7vSisq?= =?us-ascii?Q?iF6sKkuUggwsgTHWyq8keLcX0SOln3Zp4RKopD0N6wO4vdKz1C3YEkRtqV1s?= =?us-ascii?Q?auui1J3Pk3SNqa4ntDhwocPkEItJ0/YBo7LkzWnQ8bmEszOV2nQYLppjCRJX?= =?us-ascii?Q?xSDGQcHSxr4tUmLIIkewm3OiVWfZPdS2aOMRmMUDueNX7hcqAA6qHR4DMin9?= =?us-ascii?Q?Jh+W0NQeScMlgt10cQWWvgeuMtNYIu2lErZHTU7d+b2+D1kSqHhKw1C5bV0W?= =?us-ascii?Q?Ucg+B9cceAqTV3x+ngsB1Zh5AL6i5nZ+dEmbpywUH4Rt2l5pxwxVXnqO5CW+?= =?us-ascii?Q?4+y3DLnscorZClailq9sQmdfXxOGamGvTzhnBLIe9wQBPpMRtTz4d4iDVAlk?= =?us-ascii?Q?A16J+sBsO+JbHA3ftklyGGTnEnpJgPtU02w6+zImI02LOmVP+dHVRaVQ8mNY?= =?us-ascii?Q?kUkvOtOEkS3J69x00zHAax6kN5vMNbPnvAPH07BAENN87nrVyL60uNjZfsuj?= =?us-ascii?Q?m7LN3b0H7mW7Fcpnf/E1S2BTDURshVG7DZkeRur6jVwfZto/nqBCJ1BVjkjq?= =?us-ascii?Q?fiuCikHGRLr+20hXofi5aZNy9U7QzhCI8Nn+WOyC6P07D7hwegI3wPGHL1N7?= =?us-ascii?Q?dgVnYF2XfKWb2GCOpqub9yUnX+jPgzCApyKs3QSt5Gqs0oYVQfdQMg1dgHPU?= =?us-ascii?Q?Mrkf+MQmttm/ig8lwqbgBPj6NfIFboTYnqrjQHTBjCSN+LzUl6Wn1oPLv2ZL?= =?us-ascii?Q?2ug8G2gOgahHomnlCGvgue0a+hWVas/7Mb91ckgfSi0r6gEWkPXCJwGgjhQh?= =?us-ascii?Q?OgHntEOfL14P8Yfzj37+5BphEY5vB6e/QecPpqdrTePNoAzK7Nd8hffDJx5S?= =?us-ascii?Q?K5Lp/vJBSnvbpTE4LX36svqLaMzgafGcStxCi/dBIbn54wBUeQBfmvcNykyz?= =?us-ascii?Q?6EaGzUMqcRlwpr6j/1nHabgCkzZm5rd5/zi1XiSi?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 311e4e95-6c2f-4558-c929-08de1d53257d X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Nov 2025 16:40:09.0403 (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: ef4V8gNlSNLKWlwiyB+GUw01B6+AUkOYbM3XlQhwm1Q1+71kJCMiYvRDniPLMXwgdSW38/AI+tHDQxE8uTTTCg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH0PR12MB8505 On Thu, Nov 06, 2025 at 08:13:39AM +0100, Juri Lelli wrote: > Hi, > > On 29/10/25 20:08, 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: Juri Lelli > > Reviewed-by: Andrea Righi > > Signed-off-by: Joel Fernandes > > --- > > kernel/sched/debug.c | 11 ++++++++--- > > 1 file changed, 8 insertions(+), 3 deletions(-) > > > > diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c > > index 6cf9be6eea49a..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; > > > > @@ -376,8 +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? Thanks, -Andrea