1 files changed, 34 insertions, 52 deletions

diff --git a/drivers/cpuidle/governor.c b/drivers/cpuidle/governor.c
index ea2f8e7aa24a..5d0e7f78c6c5 100644
--- a/drivers/cpuidle/governor.c
+++ b/drivers/cpuidle/governor.c
@@ -8,27 +8,32 @@
  * This code is licenced under the GPL.
  */
 
+#include <linux/cpu.h>
+#include <linux/cpuidle.h>
 #include <linux/mutex.h>
 #include <linux/module.h>
-#include <linux/cpuidle.h>
+#include <linux/pm_qos.h>
 
 #include "cpuidle.h"
 
+char param_governor[CPUIDLE_NAME_LEN];
+
 LIST_HEAD(cpuidle_governors);
 struct cpuidle_governor *cpuidle_curr_governor;
+struct cpuidle_governor *cpuidle_prev_governor;
 
 /**
- * __cpuidle_find_governor - finds a governor of the specified name
+ * cpuidle_find_governor - finds a governor of the specified name
  * @str: the name
  *
  * Must be called with cpuidle_lock acquired.
  */
-static struct cpuidle_governor * __cpuidle_find_governor(const char *str)
+struct cpuidle_governor *cpuidle_find_governor(const char *str)
 {
 	struct cpuidle_governor *gov;
 
 	list_for_each_entry(gov, &cpuidle_governors, governor_list)
-		if (!strnicmp(str, gov->name, CPUIDLE_NAME_LEN))
+		if (!strncasecmp(str, gov->name, CPUIDLE_NAME_LEN))
 			return gov;
 
 	return NULL;
@@ -37,14 +42,15 @@ static struct cpuidle_governor * __cpuidle_find_governor(const char *str)
 /**
  * cpuidle_switch_governor - changes the governor
  * @gov: the new target governor
- *
- * NOTE: "gov" can be NULL to specify disabled
  * Must be called with cpuidle_lock acquired.
  */
 int cpuidle_switch_governor(struct cpuidle_governor *gov)
 {
 	struct cpuidle_device *dev;
 
+	if (!gov)
+		return -EINVAL;
+
 	if (gov == cpuidle_curr_governor)
 		return 0;
 
@@ -53,19 +59,15 @@ int cpuidle_switch_governor(struct cpuidle_governor *gov)
 	if (cpuidle_curr_governor) {
 		list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
 			cpuidle_disable_device(dev);
-		module_put(cpuidle_curr_governor->owner);
 	}
 
 	cpuidle_curr_governor = gov;
 
-	if (gov) {
-		if (!try_module_get(cpuidle_curr_governor->owner))
-			return -EINVAL;
-		list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
-			cpuidle_enable_device(dev);
-		cpuidle_install_idle_handler();
-		printk(KERN_INFO "cpuidle: using governor %s\n", gov->name);
-	}
+	list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
+		cpuidle_enable_device(dev);
+
+	cpuidle_install_idle_handler();
+	pr_info("cpuidle: using governor %s\n", gov->name);
 
 	return 0;
 }
@@ -85,11 +87,14 @@ int cpuidle_register_governor(struct cpuidle_governor *gov)
 		return -ENODEV;
 
 	mutex_lock(&cpuidle_lock);
-	if (__cpuidle_find_governor(gov->name) == NULL) {
+	if (cpuidle_find_governor(gov->name) == NULL) {
 		ret = 0;
 		list_add_tail(&gov->governor_list, &cpuidle_governors);
 		if (!cpuidle_curr_governor ||
-		    cpuidle_curr_governor->rating < gov->rating)
+		    !strncasecmp(param_governor, gov->name, CPUIDLE_NAME_LEN) ||
+		    (cpuidle_curr_governor->rating < gov->rating &&
+		     strncasecmp(param_governor, cpuidle_curr_governor->name,
+				 CPUIDLE_NAME_LEN)))
 			cpuidle_switch_governor(gov);
 	}
 	mutex_unlock(&cpuidle_lock);
@@ -98,44 +103,21 @@ int cpuidle_register_governor(struct cpuidle_governor *gov)
 }
 
 /**
- * cpuidle_replace_governor - find a replacement governor
- * @exclude_rating: the rating that will be skipped while looking for
- * new governor.
+ * cpuidle_governor_latency_req - Compute a latency constraint for CPU
+ * @cpu: Target CPU
  */
-static struct cpuidle_governor *cpuidle_replace_governor(int exclude_rating)
+s64 cpuidle_governor_latency_req(unsigned int cpu)
 {
-	struct cpuidle_governor *gov;
-	struct cpuidle_governor *ret_gov = NULL;
-	unsigned int max_rating = 0;
-
-	list_for_each_entry(gov, &cpuidle_governors, governor_list) {
-		if (gov->rating == exclude_rating)
-			continue;
-		if (gov->rating > max_rating) {
-			max_rating = gov->rating;
-			ret_gov = gov;
-		}
-	}
+	struct device *device = get_cpu_device(cpu);
+	int device_req = dev_pm_qos_raw_resume_latency(device);
+	int global_req = cpu_latency_qos_limit();
+	int global_wake_req = cpu_wakeup_latency_qos_limit();
 
-	return ret_gov;
-}
+	if (global_req > global_wake_req)
+		global_req = global_wake_req;
 
-/**
- * cpuidle_unregister_governor - unregisters a governor
- * @gov: the governor
- */
-void cpuidle_unregister_governor(struct cpuidle_governor *gov)
-{
-	if (!gov)
-		return;
+	if (device_req > global_req)
+		device_req = global_req;
 
-	mutex_lock(&cpuidle_lock);
-	if (gov == cpuidle_curr_governor) {
-		struct cpuidle_governor *new_gov;
-		new_gov = cpuidle_replace_governor(gov->rating);
-		cpuidle_switch_governor(new_gov);
-	}
-	list_del(&gov->governor_list);
-	mutex_unlock(&cpuidle_lock);
+	return (s64)device_req * NSEC_PER_USEC;
 }
-