[PATCH 2/2] PM-runtime: update time accounting only when enabled

From: Vincent Guittot
Date: Mon Feb 04 2019 - 11:26:09 EST


Update accounting_timestamp field only when PM runtime is enable
and don't forget to account the last state before disabling it.

Suggested-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
---
drivers/base/power/runtime.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index 50740da..ed62cca 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -66,11 +66,14 @@ static int rpm_suspend(struct device *dev, int rpmflags);
*/
void update_pm_runtime_accounting(struct device *dev)
{
- u64 now = ktime_get_mono_fast_ns();
- u64 last = dev->power.accounting_timestamp;
- u64 delta;
+ u64 now, last, delta;

- dev->power.accounting_timestamp = now;
+ if (dev->power.disable_depth > 0)
+ return;
+
+ last = dev->power.accounting_timestamp;
+
+ dev->power.accounting_timestamp = now = ktime_get_mono_fast_ns();

/*
* Because ktime_get_mono_fast_ns() is not monotonic during
@@ -82,9 +85,6 @@ void update_pm_runtime_accounting(struct device *dev)

delta = now - last;

- if (dev->power.disable_depth > 0)
- return;
-
if (dev->power.runtime_status == RPM_SUSPENDED)
dev->power.suspended_time += delta;
else
@@ -1298,6 +1298,9 @@ void __pm_runtime_disable(struct device *dev, bool check_resume)
pm_runtime_put_noidle(dev);
}

+ /* Update time accounting before disabling pm runtime */
+ update_pm_runtime_accounting(dev);
+
if (!dev->power.disable_depth++)
__pm_runtime_barrier(dev);

@@ -1521,7 +1524,6 @@ void pm_runtime_init(struct device *dev)
dev->power.request_pending = false;
dev->power.request = RPM_REQ_NONE;
dev->power.deferred_resume = false;
- dev->power.accounting_timestamp = 0;
INIT_WORK(&dev->power.work, pm_runtime_work);

dev->power.timer_expires = 0;
--
2.7.4