PM-runtime: Replace jiffies-based accounting with ktime-based accounting

Replace jiffies-based accounting for runtime_active_time and
runtime_suspended_time with ktime-based accounting. This makes the
runtime debug counters inline with genpd and other PM subsytems which
use ktime-based accounting.

Timekeeping is initialized before driver_init(). It's only at that time
that PM-runtime can be enabled.

Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
[switch from ktime to raw nsec]
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index f23b7ecfce3b38d9f4dec6b58361c671ef7992dc..eb1a3b878e1e985320a309f5fdfe0324fb4ebd84 100644 (file)
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -66,8 +66,8 @@ static int rpm_suspend(struct device *dev, int rpmflags);
  */
 void update_pm_runtime_accounting(struct device *dev)
 {
-       unsigned long now = jiffies;
-       unsigned long delta;
+       u64 now = ktime_to_ns(ktime_get());
+       u64 delta;
 
        delta = now - dev->power.accounting_timestamp;
 
@@ -77,9 +77,9 @@ void update_pm_runtime_accounting(struct device *dev)
                return;
 
        if (dev->power.runtime_status == RPM_SUSPENDED)
-               dev->power.suspended_jiffies += delta;
+               dev->power.suspended_time += delta;
        else
-               dev->power.active_jiffies += delta;
+               dev->power.active_time += delta;
 }
 
 static void __update_runtime_status(struct device *dev, enum rpm_status status)
@@ -90,16 +90,17 @@ static void __update_runtime_status(struct device *dev, enum rpm_status status)
 
 u64 pm_runtime_suspended_time(struct device *dev)
 {
-       unsigned long flags, time;
+       u64 time;
+       unsigned long flags;
 
        spin_lock_irqsave(&dev->power.lock, flags);
 
        update_pm_runtime_accounting(dev);
-       time = dev->power.suspended_jiffies;
+       time = dev->power.suspended_time;
 
        spin_unlock_irqrestore(&dev->power.lock, flags);
 
-       return jiffies_to_nsecs(time);
+       return time;
 }
 EXPORT_SYMBOL_GPL(pm_runtime_suspended_time);
 
@@ -1314,7 +1315,7 @@ void pm_runtime_enable(struct device *dev)
 
                /* About to enable runtime pm, set accounting_timestamp to now */
                if (!dev->power.disable_depth)
-                       dev->power.accounting_timestamp = jiffies;
+                       dev->power.accounting_timestamp = ktime_to_ns(ktime_get());
        } else {
                dev_warn(dev, "Unbalanced %s!\n", __func__);
        }

diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c
index d713738ce7967cdb8003166fc17bf63116d3b629..96c8a227610a4b99509878c8069e9083ed031f56 100644 (file)
--- a/drivers/base/power/sysfs.c
+++ b/drivers/base/power/sysfs.c
@@ -125,9 +125,12 @@ static ssize_t runtime_active_time_show(struct device *dev,
                                struct device_attribute *attr, char *buf)
 {
        int ret;
+       u64 tmp;
        spin_lock_irq(&dev->power.lock);
        update_pm_runtime_accounting(dev);
-       ret = sprintf(buf, "%i\n", jiffies_to_msecs(dev->power.active_jiffies));
+       tmp = dev->power.active_time;
+       do_div(tmp, NSEC_PER_MSEC);
+       ret = sprintf(buf, "%llu\n", tmp);
        spin_unlock_irq(&dev->power.lock);
        return ret;
 }
@@ -138,10 +141,12 @@ static ssize_t runtime_suspended_time_show(struct device *dev,
                                struct device_attribute *attr, char *buf)
 {
        int ret;
+       u64 tmp;
        spin_lock_irq(&dev->power.lock);
        update_pm_runtime_accounting(dev);
-       ret = sprintf(buf, "%i\n",
-               jiffies_to_msecs(dev->power.suspended_jiffies));
+       tmp = dev->power.suspended_time;
+       do_div(tmp, NSEC_PER_MSEC);
+       ret = sprintf(buf, "%llu\n", tmp);
        spin_unlock_irq(&dev->power.lock);
        return ret;
 }

diff --git a/include/linux/pm.h b/include/linux/pm.h
index 0bd9de116826a02a942e3162b8f4126fe3526242..3d2cbf9477682fdc3a95d70ec9d0581f0070768e 100644 (file)
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -633,9 +633,9 @@ struct dev_pm_info {
        int                     runtime_error;
        int                     autosuspend_delay;
        u64                     last_busy;
-       unsigned long           active_jiffies;
-       unsigned long           suspended_jiffies;
-       unsigned long           accounting_timestamp;
+       u64                     active_time;
+       u64                     suspended_time;
+       u64                     accounting_timestamp;
 #endif
        struct pm_subsys_data   *subsys_data;  /* Owned by the subsystem. */
        void (*set_latency_tolerance)(struct device *, s32);