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

[Jon Hunter]

On 13/01/2025 09:32, Juri Lelli wrote:
> 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?


I just noticed that by default we do boot this board with 
'isolcpus=1-2'. I see that this is a deprecated cmdline argument now and 
I must admit I don't know the history of this for this specific board. 
It is quite old now.

Thierry, I am curious if you have this set for Tegra186 or not? Looks 
like our BSP (r35 based) sets this by default.

I did try removing this and that does appear to fix it.

Juri, let me know your thoughts.

Thanks!
Jon

--
nvpublic