Re: [PATCH v2 3/2] sched/deadline: Check bandwidth overflow earlier for hotplug

[Juri Lelli <juri.lelli@redhat.com>]

On 10/01/25 18:40, Jon Hunter wrote:

...

> With the above I see the following ...
> 
> [   53.919672] dl_bw_manage: cpu=5 cap=3072 fair_server_bw=52428 total_bw=209712 dl_bw_cpus=4
> [   53.930608] dl_bw_manage: cpu=4 cap=2048 fair_server_bw=52428 total_bw=157284 dl_bw_cpus=3
> [   53.941601] dl_bw_manage: cpu=3 cap=1024 fair_server_bw=52428 total_bw=104856 dl_bw_cpus=2

So far so good.

> [   53.952186] dl_bw_manage: cpu=2 cap=1024 fair_server_bw=52428 total_bw=576708 dl_bw_cpus=2

But, this above doesn't sound right.

> [   53.962938] dl_bw_manage: cpu=1 cap=0 fair_server_bw=52428 total_bw=576708 dl_bw_cpus=1
> [   53.971068] Error taking CPU1 down: -16
> [   53.974912] Non-boot CPUs are not disabled

What is the topology of your board?

Are you using any cpuset configuration for partitioning CPUs?

Also, could you please add sched_debug to the kernel cmdline and enable
CONFIG_SCHED_DEBUG (if not enabled already)? That should print
additional information about scheduling domains in case they get
reconfigured for some reason.

Thanks!
Juri