[RFC PATCH 2/2] ASoC: codecs: rt5640: Move long delayed work on system_dfl_long_wq

[Marco Crivellari]

Currently the code enqueue work items using {queue|mod}_delayed_work(),
using system_long_wq. This workqueue should be used when long works are
expected and it is a per-cpu workqueue.

The function(s) end up calling __queue_delayed_work(), which set a global
timer that could fire anywhere, enqueuing the work where the timer fired.

Unbound works could benefit from scheduler task placement, to optimize
performance and power consumption. Long work shouldn't stick to a single
CPU.

Recently, a new unbound workqueue specific for long running work has
been added:

    c116737e972e ("workqueue: Add system_dfl_long_wq for long unbound works")

Since the workqueue work doesn't rely on per-cpu variables, there is no
obvious reason that justify the use of a per-cpu workqueue. So change
system_long_wq with system_dfl_long_wq so that the work may benefit from
scheduler task placement.

Cc: Oder Chiou <oder_chiou@xxxxxxxxxxx>
Signed-off-by: Marco Crivellari <marco.crivellari@xxxxxxxx>
---
 sound/soc/codecs/rt5640.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/sound/soc/codecs/rt5640.c b/sound/soc/codecs/rt5640.c
index f6c6294e1588..1a5bb72b7d03 100644
--- a/sound/soc/codecs/rt5640.c
+++ b/sound/soc/codecs/rt5640.c
@@ -2397,7 +2397,7 @@ static void rt5640_jack_work(struct work_struct *work)
 		 * disabled the OVCD IRQ, the IRQ pin will stay high and as
 		 * we react to edges, we miss the unplug event -> recheck.
 		 */
-		queue_delayed_work(system_long_wq, &rt5640->jack_work, 0);
+		queue_delayed_work(system_dfl_long_wq, &rt5640->jack_work, 0);
 	}
 }
 
@@ -2410,7 +2410,8 @@ static irqreturn_t rt5640_irq(int irq, void *data)
 		delay = 100;
 
 	if (rt5640->jack)
-		mod_delayed_work(system_long_wq, &rt5640->jack_work, delay);
+		mod_delayed_work(system_dfl_long_wq, &rt5640->jack_work,
+				 delay);
 
 	return IRQ_HANDLED;
 }
@@ -2419,7 +2420,7 @@ static irqreturn_t rt5640_jd_gpio_irq(int irq, void *data)
 {
 	struct rt5640_priv *rt5640 = data;
 
-	queue_delayed_work(system_long_wq, &rt5640->jack_work,
+	queue_delayed_work(system_dfl_long_wq, &rt5640->jack_work,
 			   msecs_to_jiffies(JACK_SETTLE_TIME));
 
 	return IRQ_HANDLED;
@@ -2579,7 +2580,7 @@ static void rt5640_enable_jack_detect(struct snd_soc_component *component,
 	rt5640->irq_requested = true;
 
 	/* sync initial jack state */
-	queue_delayed_work(system_long_wq, &rt5640->jack_work, 0);
+	queue_delayed_work(system_dfl_long_wq, &rt5640->jack_work, 0);
 }
 
 static const struct snd_soc_dapm_route rt5640_hda_jack_dapm_routes[] = {
@@ -2632,7 +2633,7 @@ static void rt5640_enable_hda_jack_detect(
 	rt5640->irq_requested = true;
 
 	/* sync initial jack state */
-	queue_delayed_work(system_long_wq, &rt5640->jack_work, 0);
+	queue_delayed_work(system_dfl_long_wq, &rt5640->jack_work, 0);
 
 	snd_soc_dapm_add_routes(dapm, rt5640_hda_jack_dapm_routes,
 		ARRAY_SIZE(rt5640_hda_jack_dapm_routes));
@@ -2860,7 +2861,7 @@ static int rt5640_resume(struct snd_soc_component *component)
 		}
 
 		enable_irq(rt5640->irq);
-		queue_delayed_work(system_long_wq, &rt5640->jack_work, 0);
+		queue_delayed_work(system_dfl_long_wq, &rt5640->jack_work, 0);
 	}
 
 	return 0;
-- 
2.53.0