[PATCH 3/3] PM / devfreq: Add tracepoint for frequency changes
From: Chanwoo Choi
Date: Thu Oct 08 2020 - 03:40:54 EST
From: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
Add a tracepoint for frequency changes of devfreq devices and
use it.
Signed-off-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
[cw00.choi: Move print position of tracepoint and add more information]
Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
---
drivers/devfreq/devfreq.c | 8 ++++++++
include/trace/events/devfreq.h | 28 ++++++++++++++++++++++++++++
2 files changed, 36 insertions(+)
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 5b069a8a1026..d4c4aa050efa 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -369,6 +369,14 @@ static int devfreq_set_target(struct devfreq *devfreq, unsigned long new_freq,
return err;
}
+ /*
+ * Print devfreq_frequency trace information between DEVFREQ_PRECHANGE
+ * and DEVFREQ_POSTCHANGE because for showing the correct frequency
+ * change order of between devfreq device and passive devfreq device.
+ */
+ if (trace_devfreq_frequency_enabled() && new_freq != cur_freq)
+ trace_devfreq_frequency(devfreq, new_freq, cur_freq);
+
freqs.new = new_freq;
devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE);
diff --git a/include/trace/events/devfreq.h b/include/trace/events/devfreq.h
index bd36d28d16bc..7627c620bbda 100644
--- a/include/trace/events/devfreq.h
+++ b/include/trace/events/devfreq.h
@@ -8,6 +8,34 @@
#include <linux/devfreq.h>
#include <linux/tracepoint.h>
+TRACE_EVENT(devfreq_frequency,
+ TP_PROTO(struct devfreq *devfreq, unsigned long freq,
+ unsigned long prev_freq),
+
+ TP_ARGS(devfreq, freq, prev_freq),
+
+ TP_STRUCT__entry(
+ __string(dev_name, dev_name(&devfreq->dev))
+ __field(unsigned long, freq)
+ __field(unsigned long, prev_freq)
+ __field(unsigned long, busy_time)
+ __field(unsigned long, total_time)
+ ),
+
+ TP_fast_assign(
+ __assign_str(dev_name, dev_name(&devfreq->dev));
+ __entry->freq = freq;
+ __entry->prev_freq = prev_freq;
+ __entry->busy_time = devfreq->last_status.busy_time;
+ __entry->total_time = devfreq->last_status.total_time;
+ ),
+
+ TP_printk("dev_name=%-30s freq=%-12lu prev_freq=%-12lu load=%-2lu",
+ __get_str(dev_name), __entry->freq, __entry->prev_freq,
+ __entry->total_time == 0 ? 0 :
+ (100 * __entry->busy_time) / __entry->total_time)
+);
+
TRACE_EVENT(devfreq_monitor,
TP_PROTO(struct devfreq *devfreq),
--
2.17.1