ASoC: Only run power_check() on a widget once per run
Some widgets will get power_check() run on them more than once during a
DAPM run, most commonly due to supply widgets checking to see if their
consumers are powered up. It's wasteful to do this so cache the result
of power_check() during a run. For one system I tested this on I got an
improvement of:
Power Path Neighbour
Before: 106 970 1186
After: 69 727 905
from this.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index e6a0882..c39146d 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -787,10 +787,17 @@
static int dapm_widget_power_check(struct snd_soc_dapm_widget *w)
{
+ if (w->power_checked)
+ return w->new_power;
+
if (w->force)
- return 1;
+ w->new_power = 1;
else
- return w->power_check(w);
+ w->new_power = w->power_check(w);
+
+ w->power_checked = true;
+
+ return w->new_power;
}
/* Generic check to see if a widget should be powered.
@@ -1322,6 +1329,10 @@
memset(&card->dapm_stats, 0, sizeof(card->dapm_stats));
+ list_for_each_entry(w, &card->widgets, list) {
+ w->power_checked = false;
+ }
+
/* Check which widgets we need to power and store them in
* lists indicating if they should be powered up or down. We
* only check widgets that have been flagged as dirty but note