Re: [PATCH v2 0/8] Fix SCHED_DEADLINE bandwidth accounting during suspend
From: Juri Lelli
Date: Fri Mar 07 2025 - 10:23:10 EST
Hi Jon,
On 07/03/25 11:40, Jon Hunter wrote:
> Hi Juri,
>
> On 06/03/2025 14:10, Juri Lelli wrote:
> > Hello!
> >
> > Jon reported [1] a suspend regression on a Tegra board configured to
> > boot with isolcpus and bisected it to commit 53916d5fd3c0
> > ("sched/deadline: Check bandwidth overflow earlier for hotplug").
> >
> > Root cause analysis pointed out that we are currently failing to
> > correctly clear and restore bandwidth accounting on root domains after
> > changes that initiate from partition_sched_domains(), as it is the case
> > for suspend operations on that board.
> >
> > This is v2 [2] of the proposed approach to fix the issue. With respect
> > to v1, the following implements the approach by:
> >
> > - 01: filter out DEADLINE special tasks
> > - 02: preparatory wrappers to be able to grab sched_domains_mutex on
> > UP (remove !SMP wrappers - Waiman)
> > - 03: generalize unique visiting of root domains so that we can
> > re-use the mechanism elsewhere
> > - 04: the bulk of the approach, clean and rebuild after changes
> > - 05: clean up a now redundant call
> > - 06: remove partition_and_rebuild_sched_domains() (Waiman)
> > - 07: stop exposing partition_sched_domains_locked (Waiman)
> >
> > Please test and review. The set is also available at
>
>
> Tested-by: Jon Hunter <jonathanh@xxxxxxxxxx>
Thanks!
Best,
Juri