Re: [PATCH 2/5] sched: add WF_CURRENT_CPU and externise ttwu

[Andrei Vagin]

On Wed, Oct 19, 2022 at 09:54:15PM -0700, Kees Cook wrote:
> On October 19, 2022 6:10:45 PM PDT, Andrei Vagin <avagin@xxxxxxxxx> wrote:
> >From: Peter Oskolkov <posk@xxxxxxxxxx>
> >
> >Add WF_CURRENT_CPU wake flag that advices the scheduler to
> >move the wakee to the current CPU. This is useful for fast on-CPU
> >context switching use cases such as UMCG.
> 
> UMCG is https://lwn.net/Articles/879398/ ?
> 

Yes, this is it. https://lkml.org/lkml/2021/11/4/830 is the most recent
version that I've seen.

> >In addition, make ttwu external rather than static so that
> >the flag could be passed to it from outside of sched/core.c.
> >
> >Signed-off-by: Peter Oskolkov <posk@xxxxxxxxxx>
> >Signed-off-by: Andrei Vagin <avagin@xxxxxxxxx>
> >---
> > kernel/sched/core.c  |  3 +--
> > kernel/sched/fair.c  |  4 ++++
> > kernel/sched/sched.h | 13 ++++++++-----
> > 3 files changed, 13 insertions(+), 7 deletions(-)
> 
> This would need an Ack from the sched maintainers...