Re: [PATCH 28/31] sched_ext: Add Documentation/scheduler/sched-ext.rst

[Tejun Heo]

Hello,

On Mon, Dec 12, 2022 at 11:01:42AM +0700, Bagas Sanjaya wrote:
> On Tue, Nov 29, 2022 at 10:23:10PM -1000, Tejun Heo wrote:
> > Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
> > Reviewed-by: David Vernet <dvernet@xxxxxxxx>
> > Acked-by: Josh Don <joshdon@xxxxxxxxxx>
> > Acked-by: Hao Luo <haoluo@xxxxxxxxxx>
> > Acked-by: Barret Rhoden <brho@xxxxxxxxxx>
> 
> No patch description? Really? Please write one.

That's unnecessarily grating. I can add some blurb but here's an honest
question. What pertinent information would the description contain that
shouldn't be in the doc itself?

> For patch subject, better write "Documentation: scheduler: document
> extensible scheduler class".

Sounds good.

> ---- >8 ----
> diff --git a/Documentation/scheduler/sched-ext.rst b/Documentation/scheduler/sched-ext.rst
> index a2ad963b227a1b..404b820119b4a4 100644
> --- a/Documentation/scheduler/sched-ext.rst
> +++ b/Documentation/scheduler/sched-ext.rst
> @@ -15,7 +15,8 @@ programs - the BPF scheduler.
>  
>  * The system integrity is maintained no matter what the BPF scheduler does.
>    The default scheduling behavior is restored anytime an error is detected,
> -  a runnable task stalls, or on sysrq-S.
> +  a runnable task stalls, or on invoking SysRq key sequence like
> +  :kbd:`SysRq-s`.
>  
>  Switching to and from sched_ext
>  ===============================
> @@ -35,7 +36,7 @@ case, all ``SCHED_NORMAL``, ``SCHED_BATCH``, ``SCHED_IDLE`` and
>  ``SCHED_EXT`` tasks are scheduled by sched_ext. In the example schedulers,
>  this mode can be selected with the ``-a`` option.
>  
> -Terminating the sched_ext scheduler program, triggering sysrq-S, or
> +Terminating the sched_ext scheduler program, triggering SysRq key, or
>  detection of any internal error including stalled runnable tasks aborts the
>  BPF scheduler and reverts all tasks back to CFS.
>  
> 
> > +A task is always *dispatch*ed to a dsq for execution. The task starts
> > +execution when a CPU *consume*s the task from the dsq.
> 
> Sphinx reported two warnings:
> 
> Documentation/scheduler/sched-ext.rst:117: WARNING: Inline emphasis start-string without end-string.
> Documentation/scheduler/sched-ext.rst:117: WARNING: Inline emphasis start-string without end-string.
> 
> I have to replace with quotes (since "dispatch" and "consume" have different
> meaning in this context):
> 
> ---- >8 ----
> diff --git a/Documentation/scheduler/sched-ext.rst b/Documentation/scheduler/sched-ext.rst
> index 81f78e05a6c214..a2ad963b227a1b 100644
> --- a/Documentation/scheduler/sched-ext.rst
> +++ b/Documentation/scheduler/sched-ext.rst
> @@ -114,8 +114,8 @@ there is one global FIFO (``SCX_DSQ_GLOBAL``), and one local dsq per CPU
>  (``SCX_DSQ_LOCAL``). The BPF scheduler can manage an arbitrary number of
>  dsq's using ``scx_bpf_create_dsq()`` and ``scx_bpf_destroy_dsq()``.
>  
> -A task is always *dispatch*ed to a dsq for execution. The task starts
> -execution when a CPU *consume*s the task from the dsq.
> +A task is always "dispatched" to a dsq for execution. The task starts
> +execution when a CPU "consumes" the task from the dsq.
>  
>  Internally, a CPU only executes tasks which are running on its local dsq,
>  and the ``.consume()`` operation is in fact a transfer of a task from a
> 
> Otherwise the doc LGTM.

Will apply the suggested changes.

Thanks.

-- 
tejun