ASoC: Trace and collect statistics for DAPM graph walking
One of the longest standing areas for improvement in ASoC has been the
DAPM algorithm - it repeats the same checks many times whenever it is run
and makes no effort to limit the areas of the graph it checks meaning we
do an awful lot of walks over the full graph. This has never mattered too
much as the size of the graph has generally been small in relation to the
size of the devices supported and the speed of CPUs but it is annoying.
In preparation for work on improving this insert a trace point after the
graph walk has been done. This gives us specific timing information for
the walk, and in order to give quantifiable (non-benchmark) numbers also
count every time we check a link or check the power for a widget and report
those numbers. Substantial changes in the algorithm may require tweaks to
the stats but they should be useful for simpler things.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index 4a440b5..6a1e13e 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -48,6 +48,8 @@
#include <trace/events/asoc.h>
+#define DAPM_UPDATE_STAT(widget, val) widget->dapm->card->dapm_stats.val++;
+
/* dapm power sequences - make this per codec in the future */
static int dapm_up_seq[] = {
[snd_soc_dapm_pre] = 0,
@@ -649,6 +651,8 @@
struct snd_soc_dapm_path *path;
int con = 0;
+ DAPM_UPDATE_STAT(widget, path_checks);
+
if (widget->id == snd_soc_dapm_supply)
return 0;
@@ -697,6 +701,8 @@
struct snd_soc_dapm_path *path;
int con = 0;
+ DAPM_UPDATE_STAT(widget, path_checks);
+
if (widget->id == snd_soc_dapm_supply)
return 0;
@@ -767,6 +773,8 @@
{
int in, out;
+ DAPM_UPDATE_STAT(w, power_checks);
+
in = is_connected_input_ep(w);
dapm_clear_walk(w->dapm);
out = is_connected_output_ep(w);
@@ -779,6 +787,8 @@
{
int in;
+ DAPM_UPDATE_STAT(w, power_checks);
+
if (w->active) {
in = is_connected_input_ep(w);
dapm_clear_walk(w->dapm);
@@ -793,6 +803,8 @@
{
int out;
+ DAPM_UPDATE_STAT(w, power_checks);
+
if (w->active) {
out = is_connected_output_ep(w);
dapm_clear_walk(w->dapm);
@@ -808,6 +820,8 @@
struct snd_soc_dapm_path *path;
int power = 0;
+ DAPM_UPDATE_STAT(w, power_checks);
+
/* Check if one of our outputs is connected */
list_for_each_entry(path, &w->sinks, list_source) {
if (path->weak)
@@ -1208,6 +1222,8 @@
}
}
+ memset(&card->dapm_stats, 0, sizeof(card->dapm_stats));
+
/* Check which widgets we need to power and store them in
* lists indicating if they should be powered up or down.
*/
@@ -1299,6 +1315,7 @@
list_for_each_entry(d, &card->dapm_list, list)
d->target_bias_level = bias;
+ trace_snd_soc_dapm_walk_done(card);
/* Run all the bias changes in parallel */
list_for_each_entry(d, &dapm->card->dapm_list, list)
