Re: [RFC PATCH 00/13] Core scheduling v5

[Joel Fernandes]

On Fri, Jun 26, 2020 at 11:10 AM Joel Fernandes <joel@xxxxxxxxxxxxxxxxx> wrote:
> [..]
> > What do you think about having a separate cgroup for coresched?
> > Both coresched cgroup and prctl() could co-exist where prctl could
> > be used to isolate individual process or task and coresched cgroup
> > to group trusted processes.
>
> This sounds like a fine idea to me. I wonder how Tejun and Peter feel about
> having a new attribute-less CGroup controller for core-scheduling and just
> use that for tagging. (No need to even have a tag file, just adding/removing
> to/from CGroup will tag).

Unless there are any major objections to this idea, or better ideas
for CGroup users, we will consider proposing a new CGroup controller
for this. The issue with CPU controller CGroups being they may be
configured in a way that is incompatible with tagging.

And I was also thinking of a new clone flag CLONE_CORE (which allows a
child to share a parent's core). This is because the fork-semantics
are not clear and it may be better to leave the behavior of fork to
userspace IMHO than hard-coding policy in the kernel.

Perhaps we can also discuss this at the scheduler MC at Plumbers.

Any other thoughts?

 - Joel