[deliverable/linux.git] / drivers / cpufreq / cpufreq_governor.c

/*
 * drivers/cpufreq/cpufreq_governor.c
 *
 * 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 <linux/export.h>
#include <linux/kernel_stat.h>
#include <linux/slab.h>

#include "cpufreq_governor.h"

static struct attribute_group *get_sysfs_attr(struct dbs_data *dbs_data)
{
	if (have_governor_per_policy())
		return dbs_data->cdata->attr_group_gov_pol;
	else
		return dbs_data->cdata->attr_group_gov_sys;
}

void dbs_check_cpu(struct dbs_data *dbs_data, int cpu)
{
	struct cpu_dbs_common_info *cdbs = dbs_data->cdata->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->cdata->governor == GOV_ONDEMAND)
		ignore_nice = od_tuners->ignore_nice_load;
	else
		ignore_nice = cs_tuners->ignore_nice_load;

	policy = cdbs->cur_policy;

	/* Get Absolute Load */
	for_each_cpu(j, policy->cpus) {
		struct cpu_dbs_common_info *j_cdbs;
		u64 cur_wall_time, cur_idle_time;
		unsigned int idle_time, wall_time;
		unsigned int load;
		int io_busy = 0;

		j_cdbs = dbs_data->cdata->get_cpu_cdbs(j);

		/*
		 * 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 do not add
		 * the iowait time to the cpu idle time.
		 */
		if (dbs_data->cdata->governor == GOV_ONDEMAND)
			io_busy = od_tuners->io_is_busy;
		cur_idle_time = get_cpu_idle_time(j, &cur_wall_time, io_busy);

		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 (unlikely(!wall_time || wall_time < idle_time))
			continue;

		load = 100 * (wall_time - idle_time) / wall_time;

		if (load > max_load)
			max_load = load;
	}

	dbs_data->cdata->gov_check_cpu(cpu, max_load);
}
EXPORT_SYMBOL_GPL(dbs_check_cpu);

static inline void __gov_queue_work(int cpu, struct dbs_data *dbs_data,
		unsigned int delay)
{
	struct cpu_dbs_common_info *cdbs = dbs_data->cdata->get_cpu_cdbs(cpu);

	mod_delayed_work_on(cpu, system_wq, &cdbs->work, delay);
}

void gov_queue_work(struct dbs_data *dbs_data, struct cpufreq_policy *policy,
		unsigned int delay, bool all_cpus)
{
	int i;

	if (!policy->governor_enabled)
		return;

	if (!all_cpus) {
		/*
		 * Use raw_smp_processor_id() to avoid preemptible warnings.
		 * We know that this is only called with all_cpus == false from
		 * works that have been queued with *_work_on() functions and
		 * those works are canceled during CPU_DOWN_PREPARE so they
		 * can't possibly run on any other CPU.
		 */
		__gov_queue_work(raw_smp_processor_id(), dbs_data, delay);
	} else {
		for_each_cpu(i, policy->cpus)
			__gov_queue_work(i, dbs_data, delay);
	}
}
EXPORT_SYMBOL_GPL(gov_queue_work);

static inline void gov_cancel_work(struct dbs_data *dbs_data,
		struct cpufreq_policy *policy)
{
	struct cpu_dbs_common_info *cdbs;
	int i;

	for_each_cpu(i, policy->cpus) {
		cdbs = dbs_data->cdata->get_cpu_cdbs(i);
		cancel_delayed_work_sync(&cdbs->work);
	}
}

/* Will return if we need to evaluate cpu load again or not */
bool need_load_eval(struct cpu_dbs_common_info *cdbs,
		unsigned int sampling_rate)
{
	if (policy_is_shared(cdbs->cur_policy)) {
		ktime_t time_now = ktime_get();
		s64 delta_us = ktime_us_delta(time_now, cdbs->time_stamp);

		/* Do nothing if we recently have sampled */
		if (delta_us < (s64)(sampling_rate / 2))
			return false;
		else
			cdbs->time_stamp = time_now;
	}

	return true;
}
EXPORT_SYMBOL_GPL(need_load_eval);

static void set_sampling_rate(struct dbs_data *dbs_data,
		unsigned int sampling_rate)
{
	if (dbs_data->cdata->governor == GOV_CONSERVATIVE) {
		struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
		cs_tuners->sampling_rate = sampling_rate;
	} else {
		struct od_dbs_tuners *od_tuners = dbs_data->tuners;
		od_tuners->sampling_rate = sampling_rate;
	}
}

int cpufreq_governor_dbs(struct cpufreq_policy *policy,
		struct common_dbs_data *cdata, unsigned int event)
{
	struct dbs_data *dbs_data;
	struct od_cpu_dbs_info_s *od_dbs_info = NULL;
	struct cs_cpu_dbs_info_s *cs_dbs_info = NULL;
	struct od_ops *od_ops = NULL;
	struct od_dbs_tuners *od_tuners = NULL;
	struct cs_dbs_tuners *cs_tuners = NULL;
	struct cpu_dbs_common_info *cpu_cdbs;
	unsigned int sampling_rate, latency, ignore_nice, j, cpu = policy->cpu;
	int io_busy = 0;
	int rc;

	if (have_governor_per_policy())
		dbs_data = policy->governor_data;
	else
		dbs_data = cdata->gdbs_data;

	WARN_ON(!dbs_data && (event != CPUFREQ_GOV_POLICY_INIT));

	switch (event) {
	case CPUFREQ_GOV_POLICY_INIT:
		if (have_governor_per_policy()) {
			WARN_ON(dbs_data);
		} else if (dbs_data) {
			dbs_data->usage_count++;
			policy->governor_data = dbs_data;
			return 0;
		}

		dbs_data = kzalloc(sizeof(*dbs_data), GFP_KERNEL);
		if (!dbs_data) {
			pr_err("%s: POLICY_INIT: kzalloc failed\n", __func__);
			return -ENOMEM;
		}

		dbs_data->cdata = cdata;
		dbs_data->usage_count = 1;
		rc = cdata->init(dbs_data);
		if (rc) {
			pr_err("%s: POLICY_INIT: init() failed\n", __func__);
			kfree(dbs_data);
			return rc;
		}

		if (!have_governor_per_policy())
			WARN_ON(cpufreq_get_global_kobject());

		rc = sysfs_create_group(get_governor_parent_kobj(policy),
				get_sysfs_attr(dbs_data));
		if (rc) {
			cdata->exit(dbs_data);
			kfree(dbs_data);
			return rc;
		}

		policy->governor_data = dbs_data;

		/* policy latency is in ns. Convert it to us first */
		latency = policy->cpuinfo.transition_latency / 1000;
		if (latency == 0)
			latency = 1;

		/* Bring kernel and HW constraints together */
		dbs_data->min_sampling_rate = max(dbs_data->min_sampling_rate,
				MIN_LATENCY_MULTIPLIER * latency);
		set_sampling_rate(dbs_data, max(dbs_data->min_sampling_rate,
					latency * LATENCY_MULTIPLIER));

		if ((cdata->governor == GOV_CONSERVATIVE) &&
				(!policy->governor->initialized)) {
			struct cs_ops *cs_ops = dbs_data->cdata->gov_ops;

			cpufreq_register_notifier(cs_ops->notifier_block,
					CPUFREQ_TRANSITION_NOTIFIER);
		}

		if (!have_governor_per_policy())
			cdata->gdbs_data = dbs_data;

		return 0;
	case CPUFREQ_GOV_POLICY_EXIT:
		if (!--dbs_data->usage_count) {
			sysfs_remove_group(get_governor_parent_kobj(policy),
					get_sysfs_attr(dbs_data));

			if (!have_governor_per_policy())
				cpufreq_put_global_kobject();

			if ((dbs_data->cdata->governor == GOV_CONSERVATIVE) &&
				(policy->governor->initialized == 1)) {
				struct cs_ops *cs_ops = dbs_data->cdata->gov_ops;

				cpufreq_unregister_notifier(cs_ops->notifier_block,
						CPUFREQ_TRANSITION_NOTIFIER);
			}

			cdata->exit(dbs_data);
			kfree(dbs_data);
			cdata->gdbs_data = NULL;
		}

		policy->governor_data = NULL;
		return 0;
	}

	cpu_cdbs = dbs_data->cdata->get_cpu_cdbs(cpu);

	if (dbs_data->cdata->governor == GOV_CONSERVATIVE) {
		cs_tuners = dbs_data->tuners;
		cs_dbs_info = dbs_data->cdata->get_cpu_dbs_info_s(cpu);
		sampling_rate = cs_tuners->sampling_rate;
		ignore_nice = cs_tuners->ignore_nice_load;
	} else {
		od_tuners = dbs_data->tuners;
		od_dbs_info = dbs_data->cdata->get_cpu_dbs_info_s(cpu);
		sampling_rate = od_tuners->sampling_rate;
		ignore_nice = od_tuners->ignore_nice_load;
		od_ops = dbs_data->cdata->gov_ops;
		io_busy = od_tuners->io_is_busy;
	}

	switch (event) {
	case CPUFREQ_GOV_START:
		if (!policy->cur)
			return -EINVAL;

		mutex_lock(&dbs_data->mutex);

		for_each_cpu(j, policy->cpus) {
			struct cpu_dbs_common_info *j_cdbs =
				dbs_data->cdata->get_cpu_cdbs(j);

			j_cdbs->cpu = j;
			j_cdbs->cur_policy = policy;
			j_cdbs->prev_cpu_idle = get_cpu_idle_time(j,
					       &j_cdbs->prev_cpu_wall, io_busy);
			if (ignore_nice)
				j_cdbs->prev_cpu_nice =
					kcpustat_cpu(j).cpustat[CPUTIME_NICE];

			mutex_init(&j_cdbs->timer_mutex);
			INIT_DEFERRABLE_WORK(&j_cdbs->work,
					     dbs_data->cdata->gov_dbs_timer);
		}

		/*
		 * conservative does not implement micro like ondemand
		 * governor, thus we are bound to jiffes/HZ
		 */
		if (dbs_data->cdata->governor == GOV_CONSERVATIVE) {
			cs_dbs_info->down_skip = 0;
			cs_dbs_info->enable = 1;
			cs_dbs_info->requested_freq = policy->cur;
		} else {
			od_dbs_info->rate_mult = 1;
			od_dbs_info->sample_type = OD_NORMAL_SAMPLE;
			od_ops->powersave_bias_init_cpu(cpu);
		}

		mutex_unlock(&dbs_data->mutex);

		/* Initiate timer time stamp */
		cpu_cdbs->time_stamp = ktime_get();

		gov_queue_work(dbs_data, policy,
				delay_for_sampling_rate(sampling_rate), true);
		break;

	case CPUFREQ_GOV_STOP:
		if (dbs_data->cdata->governor == GOV_CONSERVATIVE)
			cs_dbs_info->enable = 0;

		gov_cancel_work(dbs_data, policy);

		mutex_lock(&dbs_data->mutex);
		mutex_destroy(&cpu_cdbs->timer_mutex);
		cpu_cdbs->cur_policy = NULL;

		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);
Commit	Line	Data
2aacdfff	1	/*
	2	* drivers/cpufreq/cpufreq_governor.c
	3	*
	4	* CPUFREQ governors common code
	5	*
4471a34f VK	6	* Copyright (C) 2001 Russell King
	7	* (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
	8	* (C) 2003 Jun Nakajima <jun.nakajima@intel.com>
	9	* (C) 2009 Alexander Clouter <alex@digriz.org.uk>
	10	* (c) 2012 Viresh Kumar <viresh.kumar@linaro.org>
	11	*
2aacdfff	12	* This program is free software; you can redistribute it and/or modify
	13	* it under the terms of the GNU General Public License version 2 as
	14	* published by the Free Software Foundation.
	15	*/
	16
4471a34f VK	17	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
4471a34f VK	18
2aacdfff	19	#include <linux/export.h>
2aacdfff	20	#include <linux/kernel_stat.h>
4d5dcc42	21	#include <linux/slab.h>
4471a34f VK	22
	23	#include "cpufreq_governor.h"
	24
4d5dcc42 VK	25	static struct attribute_group get_sysfs_attr(struct dbs_data dbs_data)
	26	{
	27	if (have_governor_per_policy())
	28	return dbs_data->cdata->attr_group_gov_pol;
	29	else
	30	return dbs_data->cdata->attr_group_gov_sys;
	31	}
	32
4471a34f VK	33	void dbs_check_cpu(struct dbs_data *dbs_data, int cpu)
4471a34f VK	34	{
4d5dcc42	35	struct cpu_dbs_common_info *cdbs = dbs_data->cdata->get_cpu_cdbs(cpu);
4471a34f VK	36	struct od_dbs_tuners *od_tuners = dbs_data->tuners;
	37	struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
	38	struct cpufreq_policy *policy;
	39	unsigned int max_load = 0;
	40	unsigned int ignore_nice;
	41	unsigned int j;
	42
4d5dcc42	43	if (dbs_data->cdata->governor == GOV_ONDEMAND)
6c4640c3	44	ignore_nice = od_tuners->ignore_nice_load;
4471a34f	45	else
6c4640c3	46	ignore_nice = cs_tuners->ignore_nice_load;
4471a34f VK	47
	48	policy = cdbs->cur_policy;
	49
dfa5bb62	50	/* Get Absolute Load */
4471a34f VK	51	for_each_cpu(j, policy->cpus) {
4471a34f VK	52	struct cpu_dbs_common_info *j_cdbs;
9366d840 SK	53	u64 cur_wall_time, cur_idle_time;
9366d840 SK	54	unsigned int idle_time, wall_time;
4471a34f	55	unsigned int load;
9366d840	56	int io_busy = 0;
4471a34f	57
4d5dcc42	58	j_cdbs = dbs_data->cdata->get_cpu_cdbs(j);
4471a34f	59
9366d840 SK	60	/*
	61	* For the purpose of ondemand, waiting for disk IO is
	62	* an indication that you're performance critical, and
	63	* not that the system is actually idle. So do not add
	64	* the iowait time to the cpu idle time.
	65	*/
	66	if (dbs_data->cdata->governor == GOV_ONDEMAND)
	67	io_busy = od_tuners->io_is_busy;
	68	cur_idle_time = get_cpu_idle_time(j, &cur_wall_time, io_busy);
4471a34f VK	69
	70	wall_time = (unsigned int)
	71	(cur_wall_time - j_cdbs->prev_cpu_wall);
	72	j_cdbs->prev_cpu_wall = cur_wall_time;
	73
	74	idle_time = (unsigned int)
	75	(cur_idle_time - j_cdbs->prev_cpu_idle);
	76	j_cdbs->prev_cpu_idle = cur_idle_time;
	77
	78	if (ignore_nice) {
	79	u64 cur_nice;
	80	unsigned long cur_nice_jiffies;
	81
	82	cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE] -
	83	cdbs->prev_cpu_nice;
	84	/*
	85	* Assumption: nice time between sampling periods will
	86	* be less than 2^32 jiffies for 32 bit sys
	87	*/
	88	cur_nice_jiffies = (unsigned long)
	89	cputime64_to_jiffies64(cur_nice);
	90
	91	cdbs->prev_cpu_nice =
	92	kcpustat_cpu(j).cpustat[CPUTIME_NICE];
	93	idle_time += jiffies_to_usecs(cur_nice_jiffies);
	94	}
	95
4471a34f VK	96	if (unlikely(!wall_time \|\| wall_time < idle_time))
	97	continue;
	98
	99	load = 100 * (wall_time - idle_time) / wall_time;
	100
4471a34f VK	101	if (load > max_load)
	102	max_load = load;
	103	}
	104
4d5dcc42	105	dbs_data->cdata->gov_check_cpu(cpu, max_load);
4471a34f VK	106	}
	107	EXPORT_SYMBOL_GPL(dbs_check_cpu);
	108
031299b3 VK	109	static inline void __gov_queue_work(int cpu, struct dbs_data *dbs_data,
031299b3 VK	110	unsigned int delay)
4471a34f	111	{
4d5dcc42	112	struct cpu_dbs_common_info *cdbs = dbs_data->cdata->get_cpu_cdbs(cpu);
4471a34f	113
031299b3	114	mod_delayed_work_on(cpu, system_wq, &cdbs->work, delay);
4471a34f VK	115	}
4471a34f VK	116
031299b3 VK	117	void gov_queue_work(struct dbs_data dbs_data, struct cpufreq_policy policy,
031299b3 VK	118	unsigned int delay, bool all_cpus)
4471a34f	119	{
031299b3 VK	120	int i;
031299b3 VK	121
3617f2ca SB	122	if (!policy->governor_enabled)
	123	return;
	124
031299b3	125	if (!all_cpus) {
69320783 SB	126	/*
	127	* Use raw_smp_processor_id() to avoid preemptible warnings.
	128	* We know that this is only called with all_cpus == false from
	129	* works that have been queued with *_work_on() functions and
	130	* those works are canceled during CPU_DOWN_PREPARE so they
	131	* can't possibly run on any other CPU.
	132	*/
	133	__gov_queue_work(raw_smp_processor_id(), dbs_data, delay);
031299b3 VK	134	} else {
	135	for_each_cpu(i, policy->cpus)
	136	__gov_queue_work(i, dbs_data, delay);
	137	}
	138	}
	139	EXPORT_SYMBOL_GPL(gov_queue_work);
	140
	141	static inline void gov_cancel_work(struct dbs_data *dbs_data,
	142	struct cpufreq_policy *policy)
	143	{
	144	struct cpu_dbs_common_info *cdbs;
	145	int i;
58ddcead	146
031299b3 VK	147	for_each_cpu(i, policy->cpus) {
	148	cdbs = dbs_data->cdata->get_cpu_cdbs(i);
	149	cancel_delayed_work_sync(&cdbs->work);
	150	}
4471a34f VK	151	}
4471a34f VK	152
4447266b VK	153	/* Will return if we need to evaluate cpu load again or not */
	154	bool need_load_eval(struct cpu_dbs_common_info *cdbs,
	155	unsigned int sampling_rate)
	156	{
	157	if (policy_is_shared(cdbs->cur_policy)) {
	158	ktime_t time_now = ktime_get();
	159	s64 delta_us = ktime_us_delta(time_now, cdbs->time_stamp);
	160
	161	/* Do nothing if we recently have sampled */
	162	if (delta_us < (s64)(sampling_rate / 2))
	163	return false;
	164	else
	165	cdbs->time_stamp = time_now;
	166	}
	167
	168	return true;
	169	}
	170	EXPORT_SYMBOL_GPL(need_load_eval);
	171
4d5dcc42 VK	172	static void set_sampling_rate(struct dbs_data *dbs_data,
	173	unsigned int sampling_rate)
	174	{
	175	if (dbs_data->cdata->governor == GOV_CONSERVATIVE) {
	176	struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
	177	cs_tuners->sampling_rate = sampling_rate;
	178	} else {
	179	struct od_dbs_tuners *od_tuners = dbs_data->tuners;
	180	od_tuners->sampling_rate = sampling_rate;
	181	}
	182	}
	183
	184	int cpufreq_governor_dbs(struct cpufreq_policy *policy,
	185	struct common_dbs_data *cdata, unsigned int event)
4471a34f	186	{
4d5dcc42	187	struct dbs_data *dbs_data;
4471a34f VK	188	struct od_cpu_dbs_info_s *od_dbs_info = NULL;
4471a34f VK	189	struct cs_cpu_dbs_info_s *cs_dbs_info = NULL;
8eeed095	190	struct od_ops *od_ops = NULL;
4d5dcc42 VK	191	struct od_dbs_tuners *od_tuners = NULL;
4d5dcc42 VK	192	struct cs_dbs_tuners *cs_tuners = NULL;
4471a34f	193	struct cpu_dbs_common_info *cpu_cdbs;
4d5dcc42	194	unsigned int sampling_rate, latency, ignore_nice, j, cpu = policy->cpu;
9366d840	195	int io_busy = 0;
4471a34f VK	196	int rc;
4471a34f VK	197
4d5dcc42 VK	198	if (have_governor_per_policy())
	199	dbs_data = policy->governor_data;
	200	else
	201	dbs_data = cdata->gdbs_data;
	202
	203	WARN_ON(!dbs_data && (event != CPUFREQ_GOV_POLICY_INIT));
	204
	205	switch (event) {
	206	case CPUFREQ_GOV_POLICY_INIT:
	207	if (have_governor_per_policy()) {
	208	WARN_ON(dbs_data);
	209	} else if (dbs_data) {
a97c98ad	210	dbs_data->usage_count++;
4d5dcc42 VK	211	policy->governor_data = dbs_data;
	212	return 0;
	213	}
	214
	215	dbs_data = kzalloc(sizeof(*dbs_data), GFP_KERNEL);
	216	if (!dbs_data) {
	217	pr_err("%s: POLICY_INIT: kzalloc failed\n", __func__);
	218	return -ENOMEM;
	219	}
	220
	221	dbs_data->cdata = cdata;
a97c98ad	222	dbs_data->usage_count = 1;
4d5dcc42 VK	223	rc = cdata->init(dbs_data);
	224	if (rc) {
	225	pr_err("%s: POLICY_INIT: init() failed\n", __func__);
	226	kfree(dbs_data);
	227	return rc;
	228	}
	229
2361be23 VK	230	if (!have_governor_per_policy())
	231	WARN_ON(cpufreq_get_global_kobject());
	232
4d5dcc42 VK	233	rc = sysfs_create_group(get_governor_parent_kobj(policy),
	234	get_sysfs_attr(dbs_data));
	235	if (rc) {
	236	cdata->exit(dbs_data);
	237	kfree(dbs_data);
	238	return rc;
	239	}
	240
	241	policy->governor_data = dbs_data;
	242
c4afc410	243	/* policy latency is in ns. Convert it to us first */
4d5dcc42 VK	244	latency = policy->cpuinfo.transition_latency / 1000;
	245	if (latency == 0)
	246	latency = 1;
	247
	248	/* Bring kernel and HW constraints together */
	249	dbs_data->min_sampling_rate = max(dbs_data->min_sampling_rate,
	250	MIN_LATENCY_MULTIPLIER * latency);
	251	set_sampling_rate(dbs_data, max(dbs_data->min_sampling_rate,
	252	latency * LATENCY_MULTIPLIER));
	253
a97c98ad VK	254	if ((cdata->governor == GOV_CONSERVATIVE) &&
a97c98ad VK	255	(!policy->governor->initialized)) {
4d5dcc42 VK	256	struct cs_ops *cs_ops = dbs_data->cdata->gov_ops;
	257
	258	cpufreq_register_notifier(cs_ops->notifier_block,
	259	CPUFREQ_TRANSITION_NOTIFIER);
	260	}
	261
	262	if (!have_governor_per_policy())
	263	cdata->gdbs_data = dbs_data;
	264
	265	return 0;
	266	case CPUFREQ_GOV_POLICY_EXIT:
a97c98ad	267	if (!--dbs_data->usage_count) {
4d5dcc42 VK	268	sysfs_remove_group(get_governor_parent_kobj(policy),
	269	get_sysfs_attr(dbs_data));
	270
2361be23 VK	271	if (!have_governor_per_policy())
	272	cpufreq_put_global_kobject();
	273
a97c98ad VK	274	if ((dbs_data->cdata->governor == GOV_CONSERVATIVE) &&
a97c98ad VK	275	(policy->governor->initialized == 1)) {
4d5dcc42 VK	276	struct cs_ops *cs_ops = dbs_data->cdata->gov_ops;
	277
	278	cpufreq_unregister_notifier(cs_ops->notifier_block,
	279	CPUFREQ_TRANSITION_NOTIFIER);
	280	}
	281
	282	cdata->exit(dbs_data);
	283	kfree(dbs_data);
	284	cdata->gdbs_data = NULL;
	285	}
4471a34f	286
4d5dcc42 VK	287	policy->governor_data = NULL;
	288	return 0;
	289	}
	290
	291	cpu_cdbs = dbs_data->cdata->get_cpu_cdbs(cpu);
	292
	293	if (dbs_data->cdata->governor == GOV_CONSERVATIVE) {
	294	cs_tuners = dbs_data->tuners;
	295	cs_dbs_info = dbs_data->cdata->get_cpu_dbs_info_s(cpu);
	296	sampling_rate = cs_tuners->sampling_rate;
6c4640c3	297	ignore_nice = cs_tuners->ignore_nice_load;
4471a34f	298	} else {
4d5dcc42 VK	299	od_tuners = dbs_data->tuners;
	300	od_dbs_info = dbs_data->cdata->get_cpu_dbs_info_s(cpu);
	301	sampling_rate = od_tuners->sampling_rate;
6c4640c3	302	ignore_nice = od_tuners->ignore_nice_load;
4d5dcc42	303	od_ops = dbs_data->cdata->gov_ops;
9366d840	304	io_busy = od_tuners->io_is_busy;
4471a34f VK	305	}
	306
	307	switch (event) {
	308	case CPUFREQ_GOV_START:
3361b7b1	309	if (!policy->cur)
4471a34f VK	310	return -EINVAL;
	311
	312	mutex_lock(&dbs_data->mutex);
	313
4471a34f	314	for_each_cpu(j, policy->cpus) {
8eeed095	315	struct cpu_dbs_common_info *j_cdbs =
4d5dcc42	316	dbs_data->cdata->get_cpu_cdbs(j);
4471a34f	317
09dca5ae	318	j_cdbs->cpu = j;
4471a34f VK	319	j_cdbs->cur_policy = policy;
4471a34f VK	320	j_cdbs->prev_cpu_idle = get_cpu_idle_time(j,
9366d840	321	&j_cdbs->prev_cpu_wall, io_busy);
4471a34f VK	322	if (ignore_nice)
	323	j_cdbs->prev_cpu_nice =
	324	kcpustat_cpu(j).cpustat[CPUTIME_NICE];
2abfa876 RA	325
	326	mutex_init(&j_cdbs->timer_mutex);
	327	INIT_DEFERRABLE_WORK(&j_cdbs->work,
4d5dcc42	328	dbs_data->cdata->gov_dbs_timer);
4471a34f VK	329	}
4471a34f VK	330
4471a34f VK	331	/*
	332	* conservative does not implement micro like ondemand
	333	* governor, thus we are bound to jiffes/HZ
	334	*/
4d5dcc42	335	if (dbs_data->cdata->governor == GOV_CONSERVATIVE) {
8eeed095 VK	336	cs_dbs_info->down_skip = 0;
	337	cs_dbs_info->enable = 1;
	338	cs_dbs_info->requested_freq = policy->cur;
4471a34f	339	} else {
8eeed095 VK	340	od_dbs_info->rate_mult = 1;
	341	od_dbs_info->sample_type = OD_NORMAL_SAMPLE;
	342	od_ops->powersave_bias_init_cpu(cpu);
4471a34f VK	343	}
4471a34f VK	344
4471a34f VK	345	mutex_unlock(&dbs_data->mutex);
4471a34f VK	346
58ddcead FB	347	/* Initiate timer time stamp */
58ddcead FB	348	cpu_cdbs->time_stamp = ktime_get();
da53d61e	349
031299b3 VK	350	gov_queue_work(dbs_data, policy,
031299b3 VK	351	delay_for_sampling_rate(sampling_rate), true);
4471a34f VK	352	break;
	353
	354	case CPUFREQ_GOV_STOP:
4d5dcc42	355	if (dbs_data->cdata->governor == GOV_CONSERVATIVE)
4471a34f VK	356	cs_dbs_info->enable = 0;
4471a34f VK	357
031299b3	358	gov_cancel_work(dbs_data, policy);
4471a34f VK	359
	360	mutex_lock(&dbs_data->mutex);
	361	mutex_destroy(&cpu_cdbs->timer_mutex);
419e1721	362	cpu_cdbs->cur_policy = NULL;
8eeed095	363
4471a34f VK	364	mutex_unlock(&dbs_data->mutex);
	365
	366	break;
	367
	368	case CPUFREQ_GOV_LIMITS:
	369	mutex_lock(&cpu_cdbs->timer_mutex);
	370	if (policy->max < cpu_cdbs->cur_policy->cur)
	371	__cpufreq_driver_target(cpu_cdbs->cur_policy,
	372	policy->max, CPUFREQ_RELATION_H);
	373	else if (policy->min > cpu_cdbs->cur_policy->cur)
	374	__cpufreq_driver_target(cpu_cdbs->cur_policy,
	375	policy->min, CPUFREQ_RELATION_L);
	376	dbs_check_cpu(dbs_data, cpu);
	377	mutex_unlock(&cpu_cdbs->timer_mutex);
	378	break;
	379	}
	380	return 0;
	381	}
	382	EXPORT_SYMBOL_GPL(cpufreq_governor_dbs);