On Fri, Aug 29, 2025 at 04:44:28PM -0600, Jonathan Corbet wrote:
> Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx> writes:
>
> > Commit 6f63904c8f3e ("sched: add a few helpers to wake up tasks on the
> > current cpu") introduced this new function to the completion API that
> > has not been documented yet.
>
> For a change like this, it is a really good idea to copy the author of
> the original patch and others who were involved in it; I have added them
> now.
This really is a rather specialized thing -- not sure it makes sense to
have in the document.
> > Document complete_on_current_cpu() explaining what it does and when its
> > usage is justified.
> >
> > Signed-off-by: Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx>
> >
> > ---
> > Changes in v2:
> > - Rebase onto v6.17-rc1
> > - Fix patch formatting (drop --- before the Signed-off-by tag).
> > - Link to v1: https://lore.kernel.org/r/20250703-complete_on_current_cpu_doc-v1-1-262dc859b38a@xxxxxxxxx
> > ---
> > Documentation/scheduler/completion.rst | 4 ++++
> > 1 file changed, 4 insertions(+)
> >
> > diff --git a/Documentation/scheduler/completion.rst b/Documentation/scheduler/completion.rst
> > index adf0c0a56d02..db9c131f0b62 100644
> > --- a/Documentation/scheduler/completion.rst
> > +++ b/Documentation/scheduler/completion.rst
> > @@ -272,6 +272,10 @@ Signaling completion from IRQ context is fine as it will appropriately
> > lock with spin_lock_irqsave()/spin_unlock_irqrestore() and it will never
> > sleep.
> >
> > +Use complete_on_current_cpu() to wake up the task on the current CPU.
> > +It makes use of the WF_CURRENT_CPU flag to move the task to be woken up
> > +to the current CPU, achieving faster context switches. To use this variant,
> > +the context switch speed must be relevant and the optimization justified.
> >
> > try_wait_for_completion()/completion_done():
> > --------------------------------------------
> >
> > ---
> > base-commit: 8f5ae30d69d7543eee0d70083daf4de8fe15d585
> > change-id: 20250702-complete_on_current_cpu_doc-94dfc72a39f8
> >
> > Best regards,
> > --
> > Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx>
