Re: [PATCHSET sched_ext/for-6.12] sched_ext: Apply pick_next_task() updates and remove switch_class()

[Tejun Heo]

On Tue, Sep 03, 2024 at 10:03:02PM -1000, Tejun Heo wrote:
> d7b01aef9dbd ("Merge branch 'tip/sched/core' into for-6.12") received sched
> core udpates around pick_next_task() and put_prev_task(). While the merge
> commit added a minimal workaround to keep sched_ext building and mostly
> functioning, sched_ext is currently out of step with other sched classes.
> 
> This patchset brings sched_ext upto the code by replacing
> pick_next_task_scx() with pick_task_scx() which doesn't require the current
> task to be queued and can detemrine between the current task and the top of
> the local DSQ statelessly. This allows unifying regular and core-sched pick
> task paths. After the updates, sched_class->switch_class() is no longer used
> and dropped.
> 
> This change causes two subtle API changes for the BPF schedulers. Both are
> desirable and all the existing schedulers should be okay with them.
> 
> The patchset is also available in the following git branch:
> 
>  git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext.git scx-pick_task
> 
> and contains the following patches:
> 
>  0001-sched_ext-Don-t-call-put_prev_task_scx-before-pickin.patch
>  0002-sched_ext-Replace-SCX_TASK_BAL_KEEP-with-SCX_RQ_BAL_.patch
>  0003-sched_ext-Unify-regular-and-core-sched-pick-task-pat.patch
>  0004-sched_ext-Relocate-functions-in-kernel-sched-ext.c.patch
>  0005-sched_ext-Remove-switch_class_scx.patch
>  0006-sched_ext-Remove-sched_class-switch_class.patch

Applying to sched_ext/for-6.12.

Thanks.

-- 
tejun