5 files changed, 832 insertions, 873 deletions

diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c
index 181abad0726..64ef737e7e7 100644
--- a/drivers/cpufreq/cpufreq_conservative.c
+++ b/drivers/cpufreq/cpufreq_conservative.c
@@ -11,83 +11,30 @@
  * published by the Free Software Foundation.
  */
 
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/init.h>
 #include <linux/cpufreq.h>
-#include <linux/cpu.h>
-#include <linux/jiffies.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
 #include <linux/kernel_stat.h>
+#include <linux/kobject.h>
+#include <linux/module.h>
 #include <linux/mutex.h>
-#include <linux/hrtimer.h>
-#include <linux/tick.h>
-#include <linux/ktime.h>
-#include <linux/sched.h>
+#include <linux/notifier.h>
+#include <linux/percpu-defs.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
 
-/*
- * dbs is used in this file as a shortform for demandbased switching
- * It helps to keep variable names smaller, simpler
- */
+#include "cpufreq_governor.h"
 
+/* Conservative governor macors */
 #define DEF_FREQUENCY_UP_THRESHOLD		(80)
 #define DEF_FREQUENCY_DOWN_THRESHOLD		(20)
-
-/*
- * The polling frequency of this governor depends on the capability of
- * the processor. Default polling frequency is 1000 times the transition
- * latency of the processor. The governor will work on any processor with
- * transition latency <= 10mS, using appropriate sampling
- * rate.
- * For CPUs with transition latency > 10mS (mostly drivers with CPUFREQ_ETERNAL)
- * this governor will not work.
- * All times here are in uS.
- */
-#define MIN_SAMPLING_RATE_RATIO			(2)
-
-static unsigned int min_sampling_rate;
-
-#define LATENCY_MULTIPLIER			(1000)
-#define MIN_LATENCY_MULTIPLIER			(100)
 #define DEF_SAMPLING_DOWN_FACTOR		(1)
 #define MAX_SAMPLING_DOWN_FACTOR		(10)
-#define TRANSITION_LATENCY_LIMIT		(10 * 1000 * 1000)
-
-static void do_dbs_timer(struct work_struct *work);
-
-struct cpu_dbs_info_s {
-	cputime64_t prev_cpu_idle;
-	cputime64_t prev_cpu_wall;
-	cputime64_t prev_cpu_nice;
-	struct cpufreq_policy *cur_policy;
-	struct delayed_work work;
-	unsigned int down_skip;
-	unsigned int requested_freq;
-	int cpu;
-	unsigned int enable:1;
-	/*
-	 * percpu mutex that serializes governor limit change with
-	 * do_dbs_timer invocation. We do not want do_dbs_timer to run
-	 * when user is changing the governor or limits.
-	 */
-	struct mutex timer_mutex;
-};
-static DEFINE_PER_CPU(struct cpu_dbs_info_s, cs_cpu_dbs_info);
 
-static unsigned int dbs_enable;	/* number of CPUs using this policy */
+static struct dbs_data cs_dbs_data;
+static DEFINE_PER_CPU(struct cs_cpu_dbs_info_s, cs_cpu_dbs_info);
 
-/*
- * dbs_mutex protects dbs_enable in governor start/stop.
- */
-static DEFINE_MUTEX(dbs_mutex);
-
-static struct dbs_tuners {
-	unsigned int sampling_rate;
-	unsigned int sampling_down_factor;
-	unsigned int up_threshold;
-	unsigned int down_threshold;
-	unsigned int ignore_nice;
-	unsigned int freq_step;
-} dbs_tuners_ins = {
+static struct cs_dbs_tuners cs_tuners = {
 	.up_threshold = DEF_FREQUENCY_UP_THRESHOLD,
 	.down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD,
 	.sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR,
@@ -95,61 +42,121 @@ static struct dbs_tuners {
 	.freq_step = 5,
 };
 
-/* keep track of frequency transitions */
-static int
-dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
-		     void *data)
+/*
+ * Every sampling_rate, we check, if current idle time is less than 20%
+ * (default), then we try to increase frequency Every sampling_rate *
+ * sampling_down_factor, we check, if current idle time is more than 80%, then
+ * we try to decrease frequency
+ *
+ * Any frequency increase takes it to the maximum frequency. Frequency reduction
+ * happens at minimum steps of 5% (default) of maximum frequency
+ */
+static void cs_check_cpu(int cpu, unsigned int load)
 {
-	struct cpufreq_freqs *freq = data;
-	struct cpu_dbs_info_s *this_dbs_info = &per_cpu(cs_cpu_dbs_info,
-							freq->cpu);
+	struct cs_cpu_dbs_info_s *dbs_info = &per_cpu(cs_cpu_dbs_info, cpu);
+	struct cpufreq_policy *policy = dbs_info->cdbs.cur_policy;
+	unsigned int freq_target;
+
+	/*
+	 * break out if we 'cannot' reduce the speed as the user might
+	 * want freq_step to be zero
+	 */
+	if (cs_tuners.freq_step == 0)
+		return;
+
+	/* Check for frequency increase */
+	if (load > cs_tuners.up_threshold) {
+		dbs_info->down_skip = 0;
+
+		/* if we are already at full speed then break out early */
+		if (dbs_info->requested_freq == policy->max)
+			return;
+
+		freq_target = (cs_tuners.freq_step * policy->max) / 100;
+
+		/* max freq cannot be less than 100. But who knows.... */
+		if (unlikely(freq_target == 0))
+			freq_target = 5;
+
+		dbs_info->requested_freq += freq_target;
+		if (dbs_info->requested_freq > policy->max)
+			dbs_info->requested_freq = policy->max;
 
+		__cpufreq_driver_target(policy, dbs_info->requested_freq,
+			CPUFREQ_RELATION_H);
+		return;
+	}
+
+	/*
+	 * The optimal frequency is the frequency that is the lowest that can
+	 * support the current CPU usage without triggering the up policy. To be
+	 * safe, we focus 10 points under the threshold.
+	 */
+	if (load < (cs_tuners.down_threshold - 10)) {
+		freq_target = (cs_tuners.freq_step * policy->max) / 100;
+
+		dbs_info->requested_freq -= freq_target;
+		if (dbs_info->requested_freq < policy->min)
+			dbs_info->requested_freq = policy->min;
+
+		/*
+		 * if we cannot reduce the frequency anymore, break out early
+		 */
+		if (policy->cur == policy->min)
+			return;
+
+		__cpufreq_driver_target(policy, dbs_info->requested_freq,
+				CPUFREQ_RELATION_H);
+		return;
+	}
+}
+
+static void cs_dbs_timer(struct work_struct *work)
+{
+	struct cs_cpu_dbs_info_s *dbs_info = container_of(work,
+			struct cs_cpu_dbs_info_s, cdbs.work.work);
+	unsigned int cpu = dbs_info->cdbs.cpu;
+	int delay = delay_for_sampling_rate(cs_tuners.sampling_rate);
+
+	mutex_lock(&dbs_info->cdbs.timer_mutex);
+
+	dbs_check_cpu(&cs_dbs_data, cpu);
+
+	schedule_delayed_work_on(cpu, &dbs_info->cdbs.work, delay);
+	mutex_unlock(&dbs_info->cdbs.timer_mutex);
+}
+
+static int dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
+		void *data)
+{
+	struct cpufreq_freqs *freq = data;
+	struct cs_cpu_dbs_info_s *dbs_info =
+					&per_cpu(cs_cpu_dbs_info, freq->cpu);
 	struct cpufreq_policy *policy;
 
-	if (!this_dbs_info->enable)
+	if (!dbs_info->enable)
 		return 0;
 
-	policy = this_dbs_info->cur_policy;
+	policy = dbs_info->cdbs.cur_policy;
 
 	/*
-	 * we only care if our internally tracked freq moves outside
-	 * the 'valid' ranges of freqency available to us otherwise
-	 * we do not change it
+	 * we only care if our internally tracked freq moves outside the 'valid'
+	 * ranges of freqency available to us otherwise we do not change it
 	*/
-	if (this_dbs_info->requested_freq > policy->max
-			|| this_dbs_info->requested_freq < policy->min)
-		this_dbs_info->requested_freq = freq->new;
+	if (dbs_info->requested_freq > policy->max
+			|| dbs_info->requested_freq < policy->min)
+		dbs_info->requested_freq = freq->new;
 
 	return 0;
 }
 
-static struct notifier_block dbs_cpufreq_notifier_block = {
-	.notifier_call = dbs_cpufreq_notifier
-};
-
 /************************** sysfs interface ************************/
 static ssize_t show_sampling_rate_min(struct kobject *kobj,
 				      struct attribute *attr, char *buf)
 {
-	return sprintf(buf, "%u\n", min_sampling_rate);
+	return sprintf(buf, "%u\n", cs_dbs_data.min_sampling_rate);
 }
 
-define_one_global_ro(sampling_rate_min);
-
-/* cpufreq_conservative Governor Tunables */
-#define show_one(file_name, object)					\
-static ssize_t show_##file_name						\
-(struct kobject *kobj, struct attribute *attr, char *buf)		\
-{									\
-	return sprintf(buf, "%u\n", dbs_tuners_ins.object);		\
-}
-show_one(sampling_rate, sampling_rate);
-show_one(sampling_down_factor, sampling_down_factor);
-show_one(up_threshold, up_threshold);
-show_one(down_threshold, down_threshold);
-show_one(ignore_nice_load, ignore_nice);
-show_one(freq_step, freq_step);
-
 static ssize_t store_sampling_down_factor(struct kobject *a,
 					  struct attribute *b,
 					  const char *buf, size_t count)
@@ -161,7 +168,7 @@ static ssize_t store_sampling_down_factor(struct kobject *a,
 	if (ret != 1 || input > MAX_SAMPLING_DOWN_FACTOR || input < 1)
 		return -EINVAL;
 
-	dbs_tuners_ins.sampling_down_factor = input;
+	cs_tuners.sampling_down_factor = input;
 	return count;
 }
 
@@ -175,7 +182,7 @@ static ssize_t store_sampling_rate(struct kobject *a, struct attribute *b,
 	if (ret != 1)
 		return -EINVAL;
 
-	dbs_tuners_ins.sampling_rate = max(input, min_sampling_rate);
+	cs_tuners.sampling_rate = max(input, cs_dbs_data.min_sampling_rate);
 	return count;
 }
 
@@ -186,11 +193,10 @@ static ssize_t store_up_threshold(struct kobject *a, struct attribute *b,
 	int ret;
 	ret = sscanf(buf, "%u", &input);
 
-	if (ret != 1 || input > 100 ||
-			input <= dbs_tuners_ins.down_threshold)
+	if (ret != 1 || input > 100 || input <= cs_tuners.down_threshold)
 		return -EINVAL;
 
-	dbs_tuners_ins.up_threshold = input;
+	cs_tuners.up_threshold = input;
 	return count;
 }
 
@@ -203,21 +209,19 @@ static ssize_t store_down_threshold(struct kobject *a, struct attribute *b,
 
 	/* cannot be lower than 11 otherwise freq will not fall */
 	if (ret != 1 || input < 11 || input > 100 ||
-			input >= dbs_tuners_ins.up_threshold)
+			input >= cs_tuners.up_threshold)
 		return -EINVAL;
 
-	dbs_tuners_ins.down_threshold = input;
+	cs_tuners.down_threshold = input;
 	return count;
 }
 
 static ssize_t store_ignore_nice_load(struct kobject *a, struct attribute *b,
 				      const char *buf, size_t count)
 {
-	unsigned int input;
+	unsigned int input, j;
 	int ret;
 
-	unsigned int j;
-
 	ret = sscanf(buf, "%u", &input);
 	if (ret != 1)
 		return -EINVAL;
@@ -225,19 +229,20 @@ static ssize_t store_ignore_nice_load(struct kobject *a, struct attribute *b,
 	if (input > 1)
 		input = 1;
 
-	if (input == dbs_tuners_ins.ignore_nice) /* nothing to do */
+	if (input == cs_tuners.ignore_nice) /* nothing to do */
 		return count;
 
-	dbs_tuners_ins.ignore_nice = input;
+	cs_tuners.ignore_nice = input;
 
 	/* we need to re-evaluate prev_cpu_idle */
 	for_each_online_cpu(j) {
-		struct cpu_dbs_info_s *dbs_info;
+		struct cs_cpu_dbs_info_s *dbs_info;
 		dbs_info = &per_cpu(cs_cpu_dbs_info, j);
-		dbs_info->prev_cpu_idle = get_cpu_idle_time(j,
-						&dbs_info->prev_cpu_wall);
-		if (dbs_tuners_ins.ignore_nice)
-			dbs_info->prev_cpu_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE];
+		dbs_info->cdbs.prev_cpu_idle = get_cpu_idle_time(j,
+						&dbs_info->cdbs.prev_cpu_wall);
+		if (cs_tuners.ignore_nice)
+			dbs_info->cdbs.prev_cpu_nice =
+				kcpustat_cpu(j).cpustat[CPUTIME_NICE];
 	}
 	return count;
 }
@@ -255,18 +260,28 @@ static ssize_t store_freq_step(struct kobject *a, struct attribute *b,
 	if (input > 100)
 		input = 100;
 
-	/* no need to test here if freq_step is zero as the user might actually
-	 * want this, they would be crazy though :) */
-	dbs_tuners_ins.freq_step = input;
+	/*
+	 * no need to test here if freq_step is zero as the user might actually
+	 * want this, they would be crazy though :)
+	 */
+	cs_tuners.freq_step = input;
 	return count;
 }
 
+show_one(cs, sampling_rate, sampling_rate);
+show_one(cs, sampling_down_factor, sampling_down_factor);
+show_one(cs, up_threshold, up_threshold);
+show_one(cs, down_threshold, down_threshold);
+show_one(cs, ignore_nice_load, ignore_nice);
+show_one(cs, freq_step, freq_step);
+
 define_one_global_rw(sampling_rate);
 define_one_global_rw(sampling_down_factor);
 define_one_global_rw(up_threshold);
 define_one_global_rw(down_threshold);
 define_one_global_rw(ignore_nice_load);
 define_one_global_rw(freq_step);
+define_one_global_ro(sampling_rate_min);
 
 static struct attribute *dbs_attributes[] = {
 	&sampling_rate_min.attr,
@@ -279,283 +294,38 @@ static struct attribute *dbs_attributes[] = {
 	NULL
 };
 
-static struct attribute_group dbs_attr_group = {
+static struct attribute_group cs_attr_group = {
 	.attrs = dbs_attributes,
 	.name = "conservative",
 };
 
 /************************** sysfs end ************************/
 
-static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
-{
-	unsigned int load = 0;
-	unsigned int max_load = 0;
-	unsigned int freq_target;
-
-	struct cpufreq_policy *policy;
-	unsigned int j;
-
-	policy = this_dbs_info->cur_policy;
-
-	/*
-	 * Every sampling_rate, we check, if current idle time is less
-	 * than 20% (default), then we try to increase frequency
-	 * Every sampling_rate*sampling_down_factor, we check, if current
-	 * idle time is more than 80%, then we try to decrease frequency
-	 *
-	 * Any frequency increase takes it to the maximum frequency.
-	 * Frequency reduction happens at minimum steps of
-	 * 5% (default) of maximum frequency
-	 */
-
-	/* Get Absolute Load */
-	for_each_cpu(j, policy->cpus) {
-		struct cpu_dbs_info_s *j_dbs_info;
-		cputime64_t cur_wall_time, cur_idle_time;
-		unsigned int idle_time, wall_time;
-
-		j_dbs_info = &per_cpu(cs_cpu_dbs_info, j);
-
-		cur_idle_time = get_cpu_idle_time(j, &cur_wall_time);
-
-		wall_time = (unsigned int)
-			(cur_wall_time - j_dbs_info->prev_cpu_wall);
-		j_dbs_info->prev_cpu_wall = cur_wall_time;
-
-		idle_time = (unsigned int)
-			(cur_idle_time - j_dbs_info->prev_cpu_idle);
-		j_dbs_info->prev_cpu_idle = cur_idle_time;
-
-		if (dbs_tuners_ins.ignore_nice) {
-			u64 cur_nice;
-			unsigned long cur_nice_jiffies;
-
-			cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE] -
-					 j_dbs_info->prev_cpu_nice;
-			/*
-			 * Assumption: nice time between sampling periods will
-			 * be less than 2^32 jiffies for 32 bit sys
-			 */
-			cur_nice_jiffies = (unsigned long)
-					cputime64_to_jiffies64(cur_nice);
-
-			j_dbs_info->prev_cpu_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE];
-			idle_time += jiffies_to_usecs(cur_nice_jiffies);
-		}
-
-		if (unlikely(!wall_time || wall_time < idle_time))
-			continue;
-
-		load = 100 * (wall_time - idle_time) / wall_time;
-
-		if (load > max_load)
-			max_load = load;
-	}
+define_get_cpu_dbs_routines(cs_cpu_dbs_info);
 
-	/*
-	 * break out if we 'cannot' reduce the speed as the user might
-	 * want freq_step to be zero
-	 */
-	if (dbs_tuners_ins.freq_step == 0)
-		return;
-
-	/* Check for frequency increase */
-	if (max_load > dbs_tuners_ins.up_threshold) {
-		this_dbs_info->down_skip = 0;
-
-		/* if we are already at full speed then break out early */
-		if (this_dbs_info->requested_freq == policy->max)
-			return;
-
-		freq_target = (dbs_tuners_ins.freq_step * policy->max) / 100;
-
-		/* max freq cannot be less than 100. But who knows.... */
-		if (unlikely(freq_target == 0))
-			freq_target = 5;
-
-		this_dbs_info->requested_freq += freq_target;
-		if (this_dbs_info->requested_freq > policy->max)
-			this_dbs_info->requested_freq = policy->max;
-
-		__cpufreq_driver_target(policy, this_dbs_info->requested_freq,
-			CPUFREQ_RELATION_H);
-		return;
-	}
-
-	/*
-	 * The optimal frequency is the frequency that is the lowest that
-	 * can support the current CPU usage without triggering the up
-	 * policy. To be safe, we focus 10 points under the threshold.
-	 */
-	if (max_load < (dbs_tuners_ins.down_threshold - 10)) {
-		freq_target = (dbs_tuners_ins.freq_step * policy->max) / 100;
-
-		this_dbs_info->requested_freq -= freq_target;
-		if (this_dbs_info->requested_freq < policy->min)
-			this_dbs_info->requested_freq = policy->min;
-
-		/*
-		 * if we cannot reduce the frequency anymore, break out early
-		 */
-		if (policy->cur == policy->min)
-			return;
-
-		__cpufreq_driver_target(policy, this_dbs_info->requested_freq,
-				CPUFREQ_RELATION_H);
-		return;
-	}
-}
-
-static void do_dbs_timer(struct work_struct *work)
-{
-	struct cpu_dbs_info_s *dbs_info =
-		container_of(work, struct cpu_dbs_info_s, work.work);
-	unsigned int cpu = dbs_info->cpu;
-
-	/* We want all CPUs to do sampling nearly on same jiffy */
-	int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
-
-	delay -= jiffies % delay;
-
-	mutex_lock(&dbs_info->timer_mutex);
-
-	dbs_check_cpu(dbs_info);
-
-	schedule_delayed_work_on(cpu, &dbs_info->work, delay);
-	mutex_unlock(&dbs_info->timer_mutex);
-}
-
-static inline void dbs_timer_init(struct cpu_dbs_info_s *dbs_info)
-{
-	/* We want all CPUs to do sampling nearly on same jiffy */
-	int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
-	delay -= jiffies % delay;
+static struct notifier_block cs_cpufreq_notifier_block = {
+	.notifier_call = dbs_cpufreq_notifier,
+};
 
-	dbs_info->enable = 1;
-	INIT_DEFERRABLE_WORK(&dbs_info->work, do_dbs_timer);
-	schedule_delayed_work_on(dbs_info->cpu, &dbs_info->work, delay);
-}
+static struct cs_ops cs_ops = {
+	.notifier_block = &cs_cpufreq_notifier_block,
+};
 
-static inline void dbs_timer_exit(struct cpu_dbs_info_s *dbs_info)
-{
-	dbs_info->enable = 0;
-	cancel_delayed_work_sync(&dbs_info->work);
-}
+static struct dbs_data cs_dbs_data = {
+	.governor = GOV_CONSERVATIVE,
+	.attr_group = &cs_attr_group,
+	.tuners = &cs_tuners,
+	.get_cpu_cdbs = get_cpu_cdbs,
+	.get_cpu_dbs_info_s = get_cpu_dbs_info_s,
+	.gov_dbs_timer = cs_dbs_timer,
+	.gov_check_cpu = cs_check_cpu,
+	.gov_ops = &cs_ops,
+};
 
-static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
+static int cs_cpufreq_governor_dbs(struct cpufreq_policy *policy,
 				   unsigned int event)
 {
-	unsigned int cpu = policy->cpu;
-	struct cpu_dbs_info_s *this_dbs_info;
-	unsigned int j;
-	int rc;
-
-	this_dbs_info = &per_cpu(cs_cpu_dbs_info, cpu);
-
-	switch (event) {
-	case CPUFREQ_GOV_START:
-		if ((!cpu_online(cpu)) || (!policy->cur))
-			return -EINVAL;
-
-		mutex_lock(&dbs_mutex);
-
-		for_each_cpu(j, policy->cpus) {
-			struct cpu_dbs_info_s *j_dbs_info;
-			j_dbs_info = &per_cpu(cs_cpu_dbs_info, j);
-			j_dbs_info->cur_policy = policy;
-
-			j_dbs_info->prev_cpu_idle = get_cpu_idle_time(j,
-						&j_dbs_info->prev_cpu_wall);
-			if (dbs_tuners_ins.ignore_nice)
-				j_dbs_info->prev_cpu_nice =
-						kcpustat_cpu(j).cpustat[CPUTIME_NICE];
-		}
-		this_dbs_info->cpu = cpu;
-		this_dbs_info->down_skip = 0;
-		this_dbs_info->requested_freq = policy->cur;
-
-		mutex_init(&this_dbs_info->timer_mutex);
-		dbs_enable++;
-		/*
-		 * Start the timerschedule work, when this governor
-		 * is used for first time
-		 */
-		if (dbs_enable == 1) {
-			unsigned int latency;
-			/* policy latency is in nS. Convert it to uS first */
-			latency = policy->cpuinfo.transition_latency / 1000;
-			if (latency == 0)
-				latency = 1;
-
-			rc = sysfs_create_group(cpufreq_global_kobject,
-						&dbs_attr_group);
-			if (rc) {
-				mutex_unlock(&dbs_mutex);
-				return rc;
-			}
-
-			/*
-			 * conservative does not implement micro like ondemand
-			 * governor, thus we are bound to jiffes/HZ
-			 */
-			min_sampling_rate =
-				MIN_SAMPLING_RATE_RATIO * jiffies_to_usecs(10);
-			/* Bring kernel and HW constraints together */
-			min_sampling_rate = max(min_sampling_rate,
-					MIN_LATENCY_MULTIPLIER * latency);
-			dbs_tuners_ins.sampling_rate =
-				max(min_sampling_rate,
-				    latency * LATENCY_MULTIPLIER);
-
-			cpufreq_register_notifier(
-					&dbs_cpufreq_notifier_block,
-					CPUFREQ_TRANSITION_NOTIFIER);
-		}
-		mutex_unlock(&dbs_mutex);
-
-		dbs_timer_init(this_dbs_info);
-
-		break;
-
-	case CPUFREQ_GOV_STOP:
-		dbs_timer_exit(this_dbs_info);
-
-		mutex_lock(&dbs_mutex);
-		dbs_enable--;
-		mutex_destroy(&this_dbs_info->timer_mutex);
-
-		/*
-		 * Stop the timerschedule work, when this governor
-		 * is used for first time
-		 */
-		if (dbs_enable == 0)
-			cpufreq_unregister_notifier(
-					&dbs_cpufreq_notifier_block,
-					CPUFREQ_TRANSITION_NOTIFIER);
-
-		mutex_unlock(&dbs_mutex);
-		if (!dbs_enable)
-			sysfs_remove_group(cpufreq_global_kobject,
-					   &dbs_attr_group);
-
-		break;
-
-	case CPUFREQ_GOV_LIMITS:
-		mutex_lock(&this_dbs_info->timer_mutex);
-		if (policy->max < this_dbs_info->cur_policy->cur)
-			__cpufreq_driver_target(
-					this_dbs_info->cur_policy,
-					policy->max, CPUFREQ_RELATION_H);
-		else if (policy->min > this_dbs_info->cur_policy->cur)
-			__cpufreq_driver_target(
-					this_dbs_info->cur_policy,
-					policy->min, CPUFREQ_RELATION_L);
-		dbs_check_cpu(this_dbs_info);
-		mutex_unlock(&this_dbs_info->timer_mutex);
-
-		break;
-	}
-	return 0;
+	return cpufreq_governor_dbs(&cs_dbs_data, policy, event);
 }
 
 #ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
@@ -563,13 +333,14 @@ static
 #endif
 struct cpufreq_governor cpufreq_gov_conservative = {
 	.name			= "conservative",
-	.governor		= cpufreq_governor_dbs,
+	.governor		= cs_cpufreq_governor_dbs,
 	.max_transition_latency	= TRANSITION_LATENCY_LIMIT,
 	.owner			= THIS_MODULE,
 };
 
 static int __init cpufreq_gov_dbs_init(void)
 {
+	mutex_init(&cs_dbs_data.mutex);
 	return cpufreq_register_governor(&cpufreq_gov_conservative);
 }
 
@@ -578,7 +349,6 @@ static void __exit cpufreq_gov_dbs_exit(void)
 	cpufreq_unregister_governor(&cpufreq_gov_conservative);
 }
 
-
 MODULE_AUTHOR("Alexander Clouter <alex@digriz.org.uk>");
 MODULE_DESCRIPTION("'cpufreq_conservative' - A dynamic cpufreq governor for "
 		"Low Latency Frequency Transition capable processors "
diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c
index 679842a8d34..5ea2c829a79 100644
--- a/drivers/cpufreq/cpufreq_governor.c
+++ b/drivers/cpufreq/cpufreq_governor.c
@@ -3,19 +3,31 @@
  *
  * CPUFREQ governors common code
  *
+ * Copyright	(C) 2001 Russell King
+ *		(C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
+ *		(C) 2003 Jun Nakajima <jun.nakajima@intel.com>
+ *		(C) 2009 Alexander Clouter <alex@digriz.org.uk>
+ *		(c) 2012 Viresh Kumar <viresh.kumar@linaro.org>
+ *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <asm/cputime.h>
+#include <linux/cpufreq.h>
+#include <linux/cpumask.h>
 #include <linux/export.h>
 #include <linux/kernel_stat.h>
+#include <linux/mutex.h>
 #include <linux/tick.h>
 #include <linux/types.h>
-/*
- * Code picked from earlier governer implementations
- */
+#include <linux/workqueue.h>
+
+#include "cpufreq_governor.h"
+
 static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall)
 {
 	u64 idle_time;
@@ -33,9 +45,9 @@ static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall)
 
 	idle_time = cur_wall_time - busy_time;
 	if (wall)
-		*wall = cputime_to_usecs(cur_wall_time);
+		*wall = jiffies_to_usecs(cur_wall_time);
 
-	return cputime_to_usecs(idle_time);
+	return jiffies_to_usecs(idle_time);
 }
 
 cputime64_t get_cpu_idle_time(unsigned int cpu, cputime64_t *wall)
@@ -50,3 +62,257 @@ cputime64_t get_cpu_idle_time(unsigned int cpu, cputime64_t *wall)
 	return idle_time;
 }
 EXPORT_SYMBOL_GPL(get_cpu_idle_time);
+
+void dbs_check_cpu(struct dbs_data *dbs_data, int cpu)
+{
+	struct cpu_dbs_common_info *cdbs = dbs_data->get_cpu_cdbs(cpu);
+	struct od_dbs_tuners *od_tuners = dbs_data->tuners;
+	struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
+	struct cpufreq_policy *policy;
+	unsigned int max_load = 0;
+	unsigned int ignore_nice;
+	unsigned int j;
+
+	if (dbs_data->governor == GOV_ONDEMAND)
+		ignore_nice = od_tuners->ignore_nice;
+	else
+		ignore_nice = cs_tuners->ignore_nice;
+
+	policy = cdbs->cur_policy;
+
+	/* Get Absolute Load (in terms of freq for ondemand gov) */
+	for_each_cpu(j, policy->cpus) {
+		struct cpu_dbs_common_info *j_cdbs;
+		cputime64_t cur_wall_time, cur_idle_time, cur_iowait_time;
+		unsigned int idle_time, wall_time, iowait_time;
+		unsigned int load;
+
+		j_cdbs = dbs_data->get_cpu_cdbs(j);
+
+		cur_idle_time = get_cpu_idle_time(j, &cur_wall_time);
+
+		wall_time = (unsigned int)
+			(cur_wall_time - j_cdbs->prev_cpu_wall);
+		j_cdbs->prev_cpu_wall = cur_wall_time;
+
+		idle_time = (unsigned int)
+			(cur_idle_time - j_cdbs->prev_cpu_idle);
+		j_cdbs->prev_cpu_idle = cur_idle_time;
+
+		if (ignore_nice) {
+			u64 cur_nice;
+			unsigned long cur_nice_jiffies;
+
+			cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE] -
+					 cdbs->prev_cpu_nice;
+			/*
+			 * Assumption: nice time between sampling periods will
+			 * be less than 2^32 jiffies for 32 bit sys
+			 */
+			cur_nice_jiffies = (unsigned long)
+					cputime64_to_jiffies64(cur_nice);
+
+			cdbs->prev_cpu_nice =
+				kcpustat_cpu(j).cpustat[CPUTIME_NICE];
+			idle_time += jiffies_to_usecs(cur_nice_jiffies);
+		}
+
+		if (dbs_data->governor == GOV_ONDEMAND) {
+			struct od_cpu_dbs_info_s *od_j_dbs_info =
+				dbs_data->get_cpu_dbs_info_s(cpu);
+
+			cur_iowait_time = get_cpu_iowait_time_us(j,
+					&cur_wall_time);
+			if (cur_iowait_time == -1ULL)
+				cur_iowait_time = 0;
+
+			iowait_time = (unsigned int) (cur_iowait_time -
+					od_j_dbs_info->prev_cpu_iowait);
+			od_j_dbs_info->prev_cpu_iowait = cur_iowait_time;
+
+			/*
+			 * For the purpose of ondemand, waiting for disk IO is
+			 * an indication that you're performance critical, and
+			 * not that the system is actually idle. So subtract the
+			 * iowait time from the cpu idle time.
+			 */
+			if (od_tuners->io_is_busy && idle_time >= iowait_time)
+				idle_time -= iowait_time;
+		}
+
+		if (unlikely(!wall_time || wall_time < idle_time))
+			continue;
+
+		load = 100 * (wall_time - idle_time) / wall_time;
+
+		if (dbs_data->governor == GOV_ONDEMAND) {
+			int freq_avg = __cpufreq_driver_getavg(policy, j);
+			if (freq_avg <= 0)
+				freq_avg = policy->cur;
+
+			load *= freq_avg;
+		}
+
+		if (load > max_load)
+			max_load = load;
+	}
+
+	dbs_data->gov_check_cpu(cpu, max_load);
+}
+EXPORT_SYMBOL_GPL(dbs_check_cpu);
+
+static inline void dbs_timer_init(struct dbs_data *dbs_data,
+		struct cpu_dbs_common_info *cdbs, unsigned int sampling_rate)
+{
+	int delay = delay_for_sampling_rate(sampling_rate);
+
+	INIT_DEFERRABLE_WORK(&cdbs->work, dbs_data->gov_dbs_timer);
+	schedule_delayed_work_on(cdbs->cpu, &cdbs->work, delay);
+}
+
+static inline void dbs_timer_exit(struct cpu_dbs_common_info *cdbs)
+{
+	cancel_delayed_work_sync(&cdbs->work);
+}
+
+int cpufreq_governor_dbs(struct dbs_data *dbs_data,
+		struct cpufreq_policy *policy, unsigned int event)
+{
+	struct od_cpu_dbs_info_s *od_dbs_info = NULL;
+	struct cs_cpu_dbs_info_s *cs_dbs_info = NULL;
+	struct od_dbs_tuners *od_tuners = dbs_data->tuners;
+	struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
+	struct cpu_dbs_common_info *cpu_cdbs;
+	unsigned int *sampling_rate, latency, ignore_nice, j, cpu = policy->cpu;
+	int rc;
+
+	cpu_cdbs = dbs_data->get_cpu_cdbs(cpu);
+
+	if (dbs_data->governor == GOV_CONSERVATIVE) {
+		cs_dbs_info = dbs_data->get_cpu_dbs_info_s(cpu);
+		sampling_rate = &cs_tuners->sampling_rate;
+		ignore_nice = cs_tuners->ignore_nice;
+	} else {
+		od_dbs_info = dbs_data->get_cpu_dbs_info_s(cpu);
+		sampling_rate = &od_tuners->sampling_rate;
+		ignore_nice = od_tuners->ignore_nice;
+	}
+
+	switch (event) {
+	case CPUFREQ_GOV_START:
+		if ((!cpu_online(cpu)) || (!policy->cur))
+			return -EINVAL;
+
+		mutex_lock(&dbs_data->mutex);
+
+		dbs_data->enable++;
+		cpu_cdbs->cpu = cpu;
+		for_each_cpu(j, policy->cpus) {
+			struct cpu_dbs_common_info *j_cdbs;
+			j_cdbs = dbs_data->get_cpu_cdbs(j);
+
+			j_cdbs->cur_policy = policy;
+			j_cdbs->prev_cpu_idle = get_cpu_idle_time(j,
+					&j_cdbs->prev_cpu_wall);
+			if (ignore_nice)
+				j_cdbs->prev_cpu_nice =
+					kcpustat_cpu(j).cpustat[CPUTIME_NICE];
+		}
+
+		/*
+		 * Start the timerschedule work, when this governor is used for
+		 * first time
+		 */
+		if (dbs_data->enable != 1)
+			goto second_time;
+
+		rc = sysfs_create_group(cpufreq_global_kobject,
+				dbs_data->attr_group);
+		if (rc) {
+			mutex_unlock(&dbs_data->mutex);
+			return rc;
+		}
+
+		/* policy latency is in nS. Convert it to uS first */
+		latency = policy->cpuinfo.transition_latency / 1000;
+		if (latency == 0)
+			latency = 1;
+
+		/*
+		 * conservative does not implement micro like ondemand
+		 * governor, thus we are bound to jiffes/HZ
+		 */
+		if (dbs_data->governor == GOV_CONSERVATIVE) {
+			struct cs_ops *ops = dbs_data->gov_ops;
+
+			cpufreq_register_notifier(ops->notifier_block,
+					CPUFREQ_TRANSITION_NOTIFIER);
+
+			dbs_data->min_sampling_rate = MIN_SAMPLING_RATE_RATIO *
+				jiffies_to_usecs(10);
+		} else {
+			struct od_ops *ops = dbs_data->gov_ops;
+
+			od_tuners->io_is_busy = ops->io_busy();
+		}
+
+		/* Bring kernel and HW constraints together */
+		dbs_data->min_sampling_rate = max(dbs_data->min_sampling_rate,
+				MIN_LATENCY_MULTIPLIER * latency);
+		*sampling_rate = max(dbs_data->min_sampling_rate, latency *
+				LATENCY_MULTIPLIER);
+
+second_time:
+		if (dbs_data->governor == GOV_CONSERVATIVE) {
+			cs_dbs_info->down_skip = 0;
+			cs_dbs_info->enable = 1;
+			cs_dbs_info->requested_freq = policy->cur;
+		} else {
+			struct od_ops *ops = dbs_data->gov_ops;
+			od_dbs_info->rate_mult = 1;
+			od_dbs_info->sample_type = OD_NORMAL_SAMPLE;
+			ops->powersave_bias_init_cpu(cpu);
+		}
+		mutex_unlock(&dbs_data->mutex);
+
+		mutex_init(&cpu_cdbs->timer_mutex);
+		dbs_timer_init(dbs_data, cpu_cdbs, *sampling_rate);
+		break;
+
+	case CPUFREQ_GOV_STOP:
+		if (dbs_data->governor == GOV_CONSERVATIVE)
+			cs_dbs_info->enable = 0;
+
+		dbs_timer_exit(cpu_cdbs);
+
+		mutex_lock(&dbs_data->mutex);
+		mutex_destroy(&cpu_cdbs->timer_mutex);
+		dbs_data->enable--;
+		if (!dbs_data->enable) {
+			struct cs_ops *ops = dbs_data->gov_ops;
+
+			sysfs_remove_group(cpufreq_global_kobject,
+					dbs_data->attr_group);
+			if (dbs_data->governor == GOV_CONSERVATIVE)
+				cpufreq_unregister_notifier(ops->notifier_block,
+						CPUFREQ_TRANSITION_NOTIFIER);
+		}
+		mutex_unlock(&dbs_data->mutex);
+
+		break;
+
+	case CPUFREQ_GOV_LIMITS:
+		mutex_lock(&cpu_cdbs->timer_mutex);
+		if (policy->max < cpu_cdbs->cur_policy->cur)
+			__cpufreq_driver_target(cpu_cdbs->cur_policy,
+					policy->max, CPUFREQ_RELATION_H);
+		else if (policy->min > cpu_cdbs->cur_policy->cur)
+			__cpufreq_driver_target(cpu_cdbs->cur_policy,
+					policy->min, CPUFREQ_RELATION_L);
+		dbs_check_cpu(dbs_data, cpu);
+		mutex_unlock(&cpu_cdbs->timer_mutex);
+		break;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cpufreq_governor_dbs);
diff --git a/drivers/cpufreq/cpufreq_governor.h b/drivers/cpufreq/cpufreq_governor.h
new file mode 100644
index 00000000000..34e14adfc3f
--- /dev/null
+++ b/drivers/cpufreq/cpufreq_governor.h
@@ -0,0 +1,177 @@
+/*
+ * drivers/cpufreq/cpufreq_governor.h
+ *
+ * Header file for CPUFreq governors common code
+ *
+ * Copyright	(C) 2001 Russell King
+ *		(C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
+ *		(C) 2003 Jun Nakajima <jun.nakajima@intel.com>
+ *		(C) 2009 Alexander Clouter <alex@digriz.org.uk>
+ *		(c) 2012 Viresh Kumar <viresh.kumar@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _CPUFREQ_GOVERNER_H
+#define _CPUFREQ_GOVERNER_H
+
+#include <asm/cputime.h>
+#include <linux/cpufreq.h>
+#include <linux/kobject.h>
+#include <linux/mutex.h>
+#include <linux/workqueue.h>
+#include <linux/sysfs.h>
+
+/*
+ * The polling frequency depends on the capability of the processor. Default
+ * polling frequency is 1000 times the transition latency of the processor. The
+ * governor will work on any processor with transition latency <= 10mS, using
+ * appropriate sampling rate.
+ *
+ * For CPUs with transition latency > 10mS (mostly drivers with CPUFREQ_ETERNAL)
+ * this governor will not work. All times here are in uS.
+ */
+#define MIN_SAMPLING_RATE_RATIO			(2)
+#define LATENCY_MULTIPLIER			(1000)
+#define MIN_LATENCY_MULTIPLIER			(100)
+#define TRANSITION_LATENCY_LIMIT		(10 * 1000 * 1000)
+
+/* Ondemand Sampling types */
+enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE};
+
+/* Macro creating sysfs show routines */
+#define show_one(_gov, file_name, object)				\
+static ssize_t show_##file_name						\
+(struct kobject *kobj, struct attribute *attr, char *buf)		\
+{									\
+	return sprintf(buf, "%u\n", _gov##_tuners.object);		\
+}
+
+#define define_get_cpu_dbs_routines(_dbs_info)				\
+static struct cpu_dbs_common_info *get_cpu_cdbs(int cpu)		\
+{									\
+	return &per_cpu(_dbs_info, cpu).cdbs;				\
+}									\
+									\
+static void *get_cpu_dbs_info_s(int cpu)				\
+{									\
+	return &per_cpu(_dbs_info, cpu);				\
+}
+
+/*
+ * Abbreviations:
+ * dbs: used as a shortform for demand based switching It helps to keep variable
+ *	names smaller, simpler
+ * cdbs: common dbs
+ * on_*: On-demand governor
+ * cs_*: Conservative governor
+ */
+
+/* Per cpu structures */
+struct cpu_dbs_common_info {
+	int cpu;
+	cputime64_t prev_cpu_idle;
+	cputime64_t prev_cpu_wall;
+	cputime64_t prev_cpu_nice;
+	struct cpufreq_policy *cur_policy;
+	struct delayed_work work;
+	/*
+	 * percpu mutex that serializes governor limit change with gov_dbs_timer
+	 * invocation. We do not want gov_dbs_timer to run when user is changing
+	 * the governor or limits.
+	 */
+	struct mutex timer_mute