cpuidle: don't call poll_idle_init() for every cpu

poll_idle_init() just initializes drv->states[0] and so that is
required to be done only once for each driver.  Currently, it is
called from cpuidle_enable_device() which is called for every CPU
that the driver supports.  That is not required, so move it to a
better place and call it from __cpuidle_register_driver() so that
the initialization is carried out only once.

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

2 files changed, 42 insertions, 41 deletions

diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 039a807b217a..2a991e468f78 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -226,45 +226,6 @@ void cpuidle_resume(void)
         mutex_unlock(&cpuidle_lock);
 }
 
-#ifdef CONFIG_ARCH_HAS_CPU_RELAX
-static int poll_idle(struct cpuidle_device *dev,
-                struct cpuidle_driver *drv, int index)
-{
-        ktime_t t1, t2;
-        s64 diff;
-
-        t1 = ktime_get();
-        local_irq_enable();
-        while (!need_resched())
-                cpu_relax();
-
-        t2 = ktime_get();
-        diff = ktime_to_us(ktime_sub(t2, t1));
-        if (diff > INT_MAX)
-                diff = INT_MAX;
-
-        dev->last_residency = (int) diff;
-
-        return index;
-}
-
-static void poll_idle_init(struct cpuidle_driver *drv)
-{
-        struct cpuidle_state *state = &drv->states[0];
-
-        snprintf(state->name, CPUIDLE_NAME_LEN, "POLL");
-        snprintf(state->desc, CPUIDLE_DESC_LEN, "CPUIDLE CORE POLL IDLE");
-        state->exit_latency = 0;
-        state->target_residency = 0;
-        state->power_usage = -1;
-        state->flags = 0;
-        state->enter = poll_idle;
-        state->disabled = false;
-}
-#else
-static void poll_idle_init(struct cpuidle_driver *drv) {}
-#endif /* CONFIG_ARCH_HAS_CPU_RELAX */
-
 /**
  * cpuidle_enable_device - enables idle PM for a CPU
  * @dev: the CPU
@@ -294,8 +255,6 @@ int cpuidle_enable_device(struct cpuidle_device *dev)
         if (!dev->state_count)
                 dev->state_count = drv->state_count;
 
-        poll_idle_init(drv);
-
         ret = cpuidle_add_device_sysfs(dev);
         if (ret)
                 return ret;
diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
index 2458a741ad45..06dbe7c86199 100644
--- a/drivers/cpuidle/driver.c
+++ b/drivers/cpuidle/driver.c
@@ -10,6 +10,7 @@
 
 #include <linux/mutex.h>
 #include <linux/module.h>
+#include <linux/sched.h>
 #include <linux/cpuidle.h>
 #include <linux/cpumask.h>
 #include <linux/clockchips.h>
@@ -177,6 +178,45 @@ static void __cpuidle_driver_init(struct cpuidle_driver *drv)
         }
 }
 
+#ifdef CONFIG_ARCH_HAS_CPU_RELAX
+static int poll_idle(struct cpuidle_device *dev,
+                struct cpuidle_driver *drv, int index)
+{
+        ktime_t t1, t2;
+        s64 diff;
+
+        t1 = ktime_get();
+        local_irq_enable();
+        while (!need_resched())
+                cpu_relax();
+
+        t2 = ktime_get();
+        diff = ktime_to_us(ktime_sub(t2, t1));
+        if (diff > INT_MAX)
+                diff = INT_MAX;
+
+        dev->last_residency = (int) diff;
+
+        return index;
+}
+
+static void poll_idle_init(struct cpuidle_driver *drv)
+{
+        struct cpuidle_state *state = &drv->states[0];
+
+        snprintf(state->name, CPUIDLE_NAME_LEN, "POLL");
+        snprintf(state->desc, CPUIDLE_DESC_LEN, "CPUIDLE CORE POLL IDLE");
+        state->exit_latency = 0;
+        state->target_residency = 0;
+        state->power_usage = -1;
+        state->flags = 0;
+        state->enter = poll_idle;
+        state->disabled = false;
+}
+#else
+static void poll_idle_init(struct cpuidle_driver *drv) {}
+#endif /* !CONFIG_ARCH_HAS_CPU_RELAX */
+
 /**
  * __cpuidle_register_driver: register the driver
  * @drv: a valid pointer to a struct cpuidle_driver
@@ -210,6 +250,8 @@ static int __cpuidle_register_driver(struct cpuidle_driver *drv)
                 on_each_cpu_mask(drv->cpumask, cpuidle_setup_broadcast_timer,
                                  (void *)CLOCK_EVT_NOTIFY_BROADCAST_ON, 1);
 
+        poll_idle_init(drv);
+
         return 0;
 }