Re: [PATCH 0/4] Workqueue: replace system wq and change alloc_workqueue callers

[Marco Crivellari]

Hello Tejun,

Sorry for another email.

Another question / observation: I guess maintainers can't just pull
the changes and merge for the next release, if the workqueue changes
(e.g. changes in queue_work() etc) are not also merged, right?

I received a reply here, in the meantime, in "Workqueue: fs: replace
use of system_wq and add WQ_PERCPU to alloc_workqueue users"
(https://www.spinics.net/lists/kernel/msg5811817.html).

Thank you.

Marco

On Fri, Aug 15, 2025 at 8:04 PM Tejun Heo <tj@xxxxxxxxxx> wrote:
>
> Hello, Marco.
>
> On Fri, Aug 15, 2025 at 11:45:06AM +0200, Marco Crivellari wrote:
> > === Introduced Changes by this series ===
> >
> > 1) [P 1-2] Replace use of system_wq and system_unbound_wq
> >
> >               system_wq is a per-CPU workqueue, but his name is not clear.
> >               system_unbound_wq is to be used when locality is not required.
> >
> >               Because of that, system_wq has been renamed in system_percpu_wq, and
> >               system_unbound_wq has been renamed in system_dfl_wq.
> >
> > 2) [P 3] add WQ_PERCPU to remaining alloc_workqueue() users
> >
> >               Every alloc_workqueue() caller should use one among WQ_PERCPU or
> >               WQ_UNBOUND. This is actually enforced warning if both or none of them
> >               are present at the same time.
> >
> >               WQ_UNBOUND will be removed in a next release cycle.
> >
> > 3) [P 4] upgraded WQ_UNBOUND documentation
> >
> >               Added a note about the WQ_UNBOUND flag removal in a next release cycle.
> >
> >
> > Per-subsystem changes will be submitted in different series inolving also
> > maintainers.
>
> I'm afraid these are a bit intrusive for me to apply directly. Can you
> please split the patches in this and related serieses on subsystem tree
> boundaries? e.g. Network flows through the same tree but different
> filesystems often have their own trees. Please prefix the patch title with
> the respective subsystem's name. As the base patch is already in the master
> branch, you can ask each tree to take the patches. For trees that don't
> respond after a couple pings, we can route them through wq tree.
>
> Thanks.
>
> --
> tejun



-- 

Marco Crivellari

L3 Support Engineer, Technology & Product




marco.crivellari@xxxxxxxx