Re: [PATCH v3 2/2] cgroup/cpuset: reserve DL bandwidth only for root-domain moves

[Juri Lelli]

On Sat, 09 May 2026 18:20:31 +0800, Guopeng Zhang <zhangguopeng@xxxxxxxxxx> wrote:
> cpuset_can_attach() currently adds the bandwidth of all migrating
> SCHED_DEADLINE tasks to sum_migrate_dl_bw. If the source and destination
> cpuset effective CPU masks do not overlap, the whole sum is then
> reserved in the destination root domain.
> 
> set_cpus_allowed_dl(), however, subtracts bandwidth from the source
> root domain only when the affinity change really moves the task between
> root domains. A DL task can move between cpusets that are still in the
> same root domain, so including that task in sum_migrate_dl_bw can reserve
> destination bandwidth without a matching source-side subtraction.
> 
> [...]

Acked-by: Juri Lelli <juri.lelli@xxxxxxxxxx>
Tested-by: Juri Lelli <juri.lelli@xxxxxxxxxx>

-- 
Juri Lelli <juri.lelli@xxxxxxxxxx>