Re: [PATCH v3] doc: Add CPU Isolation documentation

[Frederic Weisbecker]

Le Thu, Apr 02, 2026 at 01:01:22PM +0200, Sebastian Andrzej Siewior a écrit :
> On 2026-04-02 11:47:49 [+0200], Frederic Weisbecker wrote:
> > nohz_full was introduced in v3.10 in 2013, which means this
> > documentation is overdue for 13 years.
> > 
> > Fortunately Paul wrote a part of the needed documentation a while ago,
> > especially concerning nohz_full in Documentation/timers/no_hz.rst and
> > also about per-CPU kthreads in
> > Documentation/admin-guide/kernel-per-CPU-kthreads.rst
> > 
> > Introduce a new page that gives an overview of CPU isolation in general.
> > 
> > Acked-by: Waiman Long <longman@xxxxxxxxxx>
> > Reviewed-by: Valentin Schneider <vschneid@xxxxxxxxxx>
> > Reviewed-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
> > Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
> 
> This documents also isolcpus= boot argument. The only thing that this
> argument does and runtime can not do is the managed_irq sub argument.
> This sub argument is a story of its own and it is of quite limited for
> me taste.
> 
> However, isolcpus= is marked as deprecated. I suggest to remove the
> "Deprecated - use cpusets instead" note as the static configuration is
> fine if the system is partitioned once never changed within its
> lifetime.
> Are there any objections and if so why needs this boot argument be
> removed (assuming we have a runtime equivalent knob for managed_irq)?

No objections! Thanks.

> 
> Sebastian

-- 
Frederic Weisbecker
SUSE Labs