This patch continues the effort to refactor workqueue APIs, which has begun
with the changes introducing new workqueues and a new alloc_workqueue flag:

   commit 128ea9f6ccfb ("workqueue: Add system_percpu_wq and system_dfl_wq")
   commit 930c2ea566af ("workqueue: Add new WQ_PERCPU flag")

The point of the refactoring is to eventually alter the default behavior of
workqueues to become unbound by default so that their workload placement is
optimized by the scheduler.

Before that to happen after a careful review and conversion of each individual
case, workqueue users must be converted to the better named new workqueues with
no intended behaviour changes:

   system_wq -> system_percpu_wq
   system_unbound_wq -> system_dfl_wq

This way the old obsolete workqueues (system_wq, system_unbound_wq) can be
removed in the future.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
---
 sound/soc/sdca/sdca_ump.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/sdca/sdca_ump.c b/sound/soc/sdca/sdca_ump.c
index 8aba3ff16872..96537545c1f9 100644
--- a/sound/soc/sdca/sdca_ump.c
+++ b/sound/soc/sdca/sdca_ump.c
@@ -257,6 +257,6 @@ void sdca_ump_schedule_timeout(struct delayed_work *work, unsigned int timeout_u
 	if (!timeout_us)
 		return;
 
-	queue_delayed_work(system_wq, work, usecs_to_jiffies(timeout_us));
+	queue_delayed_work(system_percpu_wq, work, usecs_to_jiffies(timeout_us));
 }
 EXPORT_SYMBOL_NS_GPL(sdca_ump_schedule_timeout, "SND_SOC_SDCA");
-- 
2.52.0

On 24/12/25 16:26, Marco Crivellari wrote:
> This patch continues the effort to refactor workqueue APIs, which has begun
> with the changes introducing new workqueues and a new alloc_workqueue flag:
> 
>     commit 128ea9f6ccfb ("workqueue: Add system_percpu_wq and system_dfl_wq")
>     commit 930c2ea566af ("workqueue: Add new WQ_PERCPU flag")
> 
> The point of the refactoring is to eventually alter the default behavior of
> workqueues to become unbound by default so that their workload placement is
> optimized by the scheduler.
> 
> Before that to happen after a careful review and conversion of each individual
> case

... so the commit message should say why this review decided that for
this individual case the best alternative queue was system_percpu_wq.

, workqueue users must be converted to the better named new workqueues with
> no intended behaviour changes:
> 
>     system_wq -> system_percpu_wq
>     system_unbound_wq -> system_dfl_wq
>

This seems to contradict the statement above that "after a careful
review .. of each individual case". This looks more like every system_wq
is converted to system_percpu_wq.

On Sat, Dec 27, 2025 at 4:15 PM Richard Fitzgerald
<rf@opensource.cirrus.com> wrote:
> [...]
> , workqueue users must be converted to the better named new workqueues with
> > no intended behaviour changes:
> >
> >     system_wq -> system_percpu_wq
> >     system_unbound_wq -> system_dfl_wq
> >
>
> This seems to contradict the statement above that "after a careful
> review .. of each individual case". This looks more like every system_wq
> is converted to system_percpu_wq.

Hi Richard,

Yes you're right. Every system_wq has been converted directly to
system_percpu_wq.

I will fix the commit log.

Thank you!


-- 

Marco Crivellari

L3 Support Engineer

On Wed, Dec 24, 2025 at 05:26:35PM +0100, Marco Crivellari wrote:

> -	queue_delayed_work(system_wq, work, usecs_to_jiffies(timeout_us));
> +	queue_delayed_work(system_percpu_wq, work, usecs_to_jiffies(timeout_us));

As with all of these thus far I am unconvinced that there was any
intention to use a percpu queue here.

On Wed, Dec 24, 2025 at 9:30 PM Mark Brown <broonie@kernel.org> wrote:
>
> On Wed, Dec 24, 2025 at 05:26:35PM +0100, Marco Crivellari wrote:
>
> > -     queue_delayed_work(system_wq, work, usecs_to_jiffies(timeout_us));
> > +     queue_delayed_work(system_percpu_wq, work, usecs_to_jiffies(timeout_us));
>
> As with all of these thus far I am unconvinced that there was any
> intention to use a percpu queue here.

Hi Mark,

I will send a new version using the unbound workqueue. :-)

Thanks!

-- 

Marco Crivellari

L3 Support Engineer