1 files changed, 178 insertions, 251 deletions

diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c
index 0ceb2eff5a7e..cce6a8d113e1 100644
--- a/drivers/cpufreq/cpufreq_conservative.c
+++ b/drivers/cpufreq/cpufreq_conservative.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  *  drivers/cpufreq/cpufreq_conservative.c
  *
@@ -5,27 +6,27 @@
  *            (C)  2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
  *                      Jun Nakajima <jun.nakajima@intel.com>
  *            (C)  2009 Alexander Clouter <alex@digriz.org.uk>
- *
- * 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.
  */
 
-#include <linux/cpufreq.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/notifier.h>
-#include <linux/percpu-defs.h>
 #include <linux/slab.h>
-#include <linux/sysfs.h>
-#include <linux/types.h>
-
 #include "cpufreq_governor.h"
 
+struct cs_policy_dbs_info {
+	struct policy_dbs_info policy_dbs;
+	unsigned int down_skip;
+	unsigned int requested_freq;
+};
+
+static inline struct cs_policy_dbs_info *to_dbs_info(struct policy_dbs_info *policy_dbs)
+{
+	return container_of(policy_dbs, struct cs_policy_dbs_info, policy_dbs);
+}
+
+struct cs_dbs_tuners {
+	unsigned int down_threshold;
+	unsigned int freq_step;
+};
+
 /* Conservative governor macros */
 #define DEF_FREQUENCY_UP_THRESHOLD		(80)
 #define DEF_FREQUENCY_DOWN_THRESHOLD		(20)
@@ -33,18 +34,16 @@
 #define DEF_SAMPLING_DOWN_FACTOR		(1)
 #define MAX_SAMPLING_DOWN_FACTOR		(10)
 
-static DEFINE_PER_CPU(struct cs_cpu_dbs_info_s, cs_cpu_dbs_info);
-
-static inline unsigned int get_freq_target(struct cs_dbs_tuners *cs_tuners,
-					   struct cpufreq_policy *policy)
+static inline unsigned int get_freq_step(struct cs_dbs_tuners *cs_tuners,
+					 struct cpufreq_policy *policy)
 {
-	unsigned int freq_target = (cs_tuners->freq_step * policy->max) / 100;
+	unsigned int freq_step = (cs_tuners->freq_step * policy->max) / 100;
 
 	/* max freq cannot be less than 100. But who knows... */
-	if (unlikely(freq_target == 0))
-		freq_target = DEF_FREQUENCY_STEP;
+	if (unlikely(freq_step == 0))
+		freq_step = DEF_FREQUENCY_STEP;
 
-	return freq_target;
+	return freq_step;
 }
 
 /*
@@ -53,43 +52,74 @@ static inline unsigned int get_freq_target(struct cs_dbs_tuners *cs_tuners,
  * sampling_down_factor, we check, if current idle time is more than 80%
  * (default), 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
+ * Frequency updates happen at minimum steps of 5% (default) of maximum
+ * frequency
  */
-static void cs_check_cpu(int cpu, unsigned int load)
+static unsigned int cs_dbs_update(struct cpufreq_policy *policy)
 {
-	struct cs_cpu_dbs_info_s *dbs_info = &per_cpu(cs_cpu_dbs_info, cpu);
-	struct cpufreq_policy *policy = dbs_info->cdbs.cur_policy;
-	struct dbs_data *dbs_data = policy->governor_data;
+	struct policy_dbs_info *policy_dbs = policy->governor_data;
+	struct cs_policy_dbs_info *dbs_info = to_dbs_info(policy_dbs);
+	unsigned int requested_freq = dbs_info->requested_freq;
+	struct dbs_data *dbs_data = policy_dbs->dbs_data;
 	struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
+	unsigned int load = dbs_update(policy);
+	unsigned int freq_step;
 
 	/*
 	 * 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;
+		goto out;
+
+	/*
+	 * If requested_freq is out of range, it is likely that the limits
+	 * changed in the meantime, so fall back to current frequency in that
+	 * case.
+	 */
+	if (requested_freq > policy->max || requested_freq < policy->min) {
+		requested_freq = policy->cur;
+		dbs_info->requested_freq = requested_freq;
+	}
+
+	freq_step = get_freq_step(cs_tuners, policy);
+
+	/*
+	 * Decrease requested_freq one freq_step for each idle period that
+	 * we didn't update the frequency.
+	 */
+	if (policy_dbs->idle_periods < UINT_MAX) {
+		unsigned int freq_steps = policy_dbs->idle_periods * freq_step;
+
+		if (requested_freq > policy->min + freq_steps)
+			requested_freq -= freq_steps;
+		else
+			requested_freq = policy->min;
+
+		policy_dbs->idle_periods = UINT_MAX;
+	}
 
 	/* Check for frequency increase */
-	if (load > cs_tuners->up_threshold) {
+	if (load > dbs_data->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;
+		if (requested_freq == policy->max)
+			goto out;
 
-		dbs_info->requested_freq += get_freq_target(cs_tuners, policy);
-		if (dbs_info->requested_freq > policy->max)
-			dbs_info->requested_freq = policy->max;
+		requested_freq += freq_step;
+		if (requested_freq > policy->max)
+			requested_freq = policy->max;
 
-		__cpufreq_driver_target(policy, dbs_info->requested_freq,
-			CPUFREQ_RELATION_H);
-		return;
+		__cpufreq_driver_target(policy, requested_freq,
+					CPUFREQ_RELATION_HE);
+		dbs_info->requested_freq = requested_freq;
+		goto out;
 	}
 
 	/* if sampling_down_factor is active break out early */
-	if (++dbs_info->down_skip < cs_tuners->sampling_down_factor)
-		return;
+	if (++dbs_info->down_skip < dbs_data->sampling_down_factor)
+		goto out;
 	dbs_info->down_skip = 0;
 
 	/* Check for frequency decrease */
@@ -97,172 +127,109 @@ static void cs_check_cpu(int cpu, unsigned int load)
 		/*
 		 * if we cannot reduce the frequency anymore, break out early
 		 */
-		if (policy->cur == policy->min)
-			return;
+		if (requested_freq == policy->min)
+			goto out;
 
-		dbs_info->requested_freq -= get_freq_target(cs_tuners, policy);
-		if (dbs_info->requested_freq < policy->min)
-			dbs_info->requested_freq = policy->min;
+		if (requested_freq > freq_step)
+			requested_freq -= freq_step;
+		else
+			requested_freq = policy->min;
 
-		__cpufreq_driver_target(policy, dbs_info->requested_freq,
-				CPUFREQ_RELATION_L);
-		return;
+		__cpufreq_driver_target(policy, requested_freq,
+					CPUFREQ_RELATION_LE);
+		dbs_info->requested_freq = requested_freq;
 	}
-}
 
-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.cur_policy->cpu;
-	struct cs_cpu_dbs_info_s *core_dbs_info = &per_cpu(cs_cpu_dbs_info,
-			cpu);
-	struct dbs_data *dbs_data = dbs_info->cdbs.cur_policy->governor_data;
-	struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
-	int delay = delay_for_sampling_rate(cs_tuners->sampling_rate);
-	bool modify_all = true;
-
-	mutex_lock(&core_dbs_info->cdbs.timer_mutex);
-	if (!need_load_eval(&core_dbs_info->cdbs, cs_tuners->sampling_rate))
-		modify_all = false;
-	else
-		dbs_check_cpu(dbs_data, cpu);
-
-	gov_queue_work(dbs_data, dbs_info->cdbs.cur_policy, delay, modify_all);
-	mutex_unlock(&core_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 (!dbs_info->enable)
-		return 0;
-
-	policy = dbs_info->cdbs.cur_policy;
-
-	/*
-	 * we only care if our internally tracked freq moves outside the 'valid'
-	 * ranges of frequency available to us otherwise we do not change it
-	*/
-	if (dbs_info->requested_freq > policy->max
-			|| dbs_info->requested_freq < policy->min)
-		dbs_info->requested_freq = freq->new;
-
-	return 0;
+ out:
+	return dbs_data->sampling_rate;
 }
 
 /************************** sysfs interface ************************/
-static struct common_dbs_data cs_dbs_cdata;
 
-static ssize_t store_sampling_down_factor(struct dbs_data *dbs_data,
-		const char *buf, size_t count)
+static ssize_t sampling_down_factor_store(struct gov_attr_set *attr_set,
+					  const char *buf, size_t count)
 {
-	struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
+	struct dbs_data *dbs_data = to_dbs_data(attr_set);
 	unsigned int input;
 	int ret;
-	ret = sscanf(buf, "%u", &input);
+	ret = kstrtouint(buf, 0, &input);
 
-	if (ret != 1 || input > MAX_SAMPLING_DOWN_FACTOR || input < 1)
+	if (ret || input > MAX_SAMPLING_DOWN_FACTOR || input < 1)
 		return -EINVAL;
 
-	cs_tuners->sampling_down_factor = input;
+	dbs_data->sampling_down_factor = input;
 	return count;
 }
 
-static ssize_t store_sampling_rate(struct dbs_data *dbs_data, const char *buf,
-		size_t count)
+static ssize_t up_threshold_store(struct gov_attr_set *attr_set,
+				  const char *buf, size_t count)
 {
+	struct dbs_data *dbs_data = to_dbs_data(attr_set);
 	struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
 	unsigned int input;
 	int ret;
-	ret = sscanf(buf, "%u", &input);
+	ret = kstrtouint(buf, 0, &input);
 
-	if (ret != 1)
+	if (ret || input > 100 || input <= cs_tuners->down_threshold)
 		return -EINVAL;
 
-	cs_tuners->sampling_rate = max(input, dbs_data->min_sampling_rate);
+	dbs_data->up_threshold = input;
 	return count;
 }
 
-static ssize_t store_up_threshold(struct dbs_data *dbs_data, const char *buf,
-		size_t count)
+static ssize_t down_threshold_store(struct gov_attr_set *attr_set,
+				    const char *buf, size_t count)
 {
+	struct dbs_data *dbs_data = to_dbs_data(attr_set);
 	struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
 	unsigned int input;
 	int ret;
-	ret = sscanf(buf, "%u", &input);
+	ret = kstrtouint(buf, 0, &input);
 
-	if (ret != 1 || input > 100 || input <= cs_tuners->down_threshold)
-		return -EINVAL;
-
-	cs_tuners->up_threshold = input;
-	return count;
-}
-
-static ssize_t store_down_threshold(struct dbs_data *dbs_data, const char *buf,
-		size_t count)
-{
-	struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
-	unsigned int input;
-	int ret;
-	ret = sscanf(buf, "%u", &input);
-
-	/* cannot be lower than 11 otherwise freq will not fall */
-	if (ret != 1 || input < 11 || input > 100 ||
-			input >= cs_tuners->up_threshold)
+	/* cannot be lower than 1 otherwise freq will not fall */
+	if (ret || input < 1 || input >= dbs_data->up_threshold)
 		return -EINVAL;
 
 	cs_tuners->down_threshold = input;
 	return count;
 }
 
-static ssize_t store_ignore_nice(struct dbs_data *dbs_data, const char *buf,
-		size_t count)
+static ssize_t ignore_nice_load_store(struct gov_attr_set *attr_set,
+				      const char *buf, size_t count)
 {
-	struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
-	unsigned int input, j;
+	struct dbs_data *dbs_data = to_dbs_data(attr_set);
+	unsigned int input;
 	int ret;
 
-	ret = sscanf(buf, "%u", &input);
-	if (ret != 1)
-		return -EINVAL;
+	ret = kstrtouint(buf, 0, &input);
+	if (ret)
+		return ret;
 
 	if (input > 1)
 		input = 1;
 
-	if (input == cs_tuners->ignore_nice) /* nothing to do */
+	if (input == dbs_data->ignore_nice_load) /* nothing to do */
 		return count;
 
-	cs_tuners->ignore_nice = input;
+	dbs_data->ignore_nice_load = input;
 
 	/* we need to re-evaluate prev_cpu_idle */
-	for_each_online_cpu(j) {
-		struct cs_cpu_dbs_info_s *dbs_info;
-		dbs_info = &per_cpu(cs_cpu_dbs_info, j);
-		dbs_info->cdbs.prev_cpu_idle = get_cpu_idle_time(j,
-					&dbs_info->cdbs.prev_cpu_wall, 0);
-		if (cs_tuners->ignore_nice)
-			dbs_info->cdbs.prev_cpu_nice =
-				kcpustat_cpu(j).cpustat[CPUTIME_NICE];
-	}
+	gov_update_cpu_data(dbs_data);
+
 	return count;
 }
 
-static ssize_t store_freq_step(struct dbs_data *dbs_data, const char *buf,
-		size_t count)
+static ssize_t freq_step_store(struct gov_attr_set *attr_set, const char *buf,
+			       size_t count)
 {
+	struct dbs_data *dbs_data = to_dbs_data(attr_set);
 	struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
 	unsigned int input;
 	int ret;
-	ret = sscanf(buf, "%u", &input);
+	ret = kstrtouint(buf, 0, &input);
 
-	if (ret != 1)
-		return -EINVAL;
+	if (ret)
+		return ret;
 
 	if (input > 100)
 		input = 100;
@@ -275,76 +242,61 @@ static ssize_t store_freq_step(struct dbs_data *dbs_data, const char *buf,
 	return count;
 }
 
-show_store_one(cs, sampling_rate);
-show_store_one(cs, sampling_down_factor);
-show_store_one(cs, up_threshold);
-show_store_one(cs, down_threshold);
-show_store_one(cs, ignore_nice);
-show_store_one(cs, freq_step);
-declare_show_sampling_rate_min(cs);
-
-gov_sys_pol_attr_rw(sampling_rate);
-gov_sys_pol_attr_rw(sampling_down_factor);
-gov_sys_pol_attr_rw(up_threshold);
-gov_sys_pol_attr_rw(down_threshold);
-gov_sys_pol_attr_rw(ignore_nice);
-gov_sys_pol_attr_rw(freq_step);
-gov_sys_pol_attr_ro(sampling_rate_min);
-
-static struct attribute *dbs_attributes_gov_sys[] = {
-	&sampling_rate_min_gov_sys.attr,
-	&sampling_rate_gov_sys.attr,
-	&sampling_down_factor_gov_sys.attr,
-	&up_threshold_gov_sys.attr,
-	&down_threshold_gov_sys.attr,
-	&ignore_nice_gov_sys.attr,
-	&freq_step_gov_sys.attr,
+gov_show_one_common(sampling_rate);
+gov_show_one_common(sampling_down_factor);
+gov_show_one_common(up_threshold);
+gov_show_one_common(ignore_nice_load);
+gov_show_one(cs, down_threshold);
+gov_show_one(cs, freq_step);
+
+gov_attr_rw(sampling_rate);
+gov_attr_rw(sampling_down_factor);
+gov_attr_rw(up_threshold);
+gov_attr_rw(ignore_nice_load);
+gov_attr_rw(down_threshold);
+gov_attr_rw(freq_step);
+
+static struct attribute *cs_attrs[] = {
+	&sampling_rate.attr,
+	&sampling_down_factor.attr,
+	&up_threshold.attr,
+	&down_threshold.attr,
+	&ignore_nice_load.attr,
+	&freq_step.attr,
 	NULL
 };
+ATTRIBUTE_GROUPS(cs);
 
-static struct attribute_group cs_attr_group_gov_sys = {
-	.attrs = dbs_attributes_gov_sys,
-	.name = "conservative",
-};
+/************************** sysfs end ************************/
 
-static struct attribute *dbs_attributes_gov_pol[] = {
-	&sampling_rate_min_gov_pol.attr,
-	&sampling_rate_gov_pol.attr,
-	&sampling_down_factor_gov_pol.attr,
-	&up_threshold_gov_pol.attr,
-	&down_threshold_gov_pol.attr,
-	&ignore_nice_gov_pol.attr,
-	&freq_step_gov_pol.attr,
-	NULL
-};
+static struct policy_dbs_info *cs_alloc(void)
+{
+	struct cs_policy_dbs_info *dbs_info;
 
-static struct attribute_group cs_attr_group_gov_pol = {
-	.attrs = dbs_attributes_gov_pol,
-	.name = "conservative",
-};
+	dbs_info = kzalloc(sizeof(*dbs_info), GFP_KERNEL);
+	return dbs_info ? &dbs_info->policy_dbs : NULL;
+}
 
-/************************** sysfs end ************************/
+static void cs_free(struct policy_dbs_info *policy_dbs)
+{
+	kfree(to_dbs_info(policy_dbs));
+}
 
 static int cs_init(struct dbs_data *dbs_data)
 {
 	struct cs_dbs_tuners *tuners;
 
-	tuners = kzalloc(sizeof(struct cs_dbs_tuners), GFP_KERNEL);
-	if (!tuners) {
-		pr_err("%s: kzalloc failed\n", __func__);
+	tuners = kzalloc(sizeof(*tuners), GFP_KERNEL);
+	if (!tuners)
 		return -ENOMEM;
-	}
 
-	tuners->up_threshold = DEF_FREQUENCY_UP_THRESHOLD;
 	tuners->down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD;
-	tuners->sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR;
-	tuners->ignore_nice = 0;
 	tuners->freq_step = DEF_FREQUENCY_STEP;
-
+	dbs_data->up_threshold = DEF_FREQUENCY_UP_THRESHOLD;
+	dbs_data->sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR;
+	dbs_data->ignore_nice_load = 0;
 	dbs_data->tuners = tuners;
-	dbs_data->min_sampling_rate = MIN_SAMPLING_RATE_RATIO *
-		jiffies_to_usecs(10);
-	mutex_init(&dbs_data->mutex);
+
 	return 0;
 }
 
@@ -353,54 +305,26 @@ static void cs_exit(struct dbs_data *dbs_data)
 	kfree(dbs_data->tuners);
 }
 
-define_get_cpu_dbs_routines(cs_cpu_dbs_info);
-
-static struct notifier_block cs_cpufreq_notifier_block = {
-	.notifier_call = dbs_cpufreq_notifier,
-};
+static void cs_start(struct cpufreq_policy *policy)
+{
+	struct cs_policy_dbs_info *dbs_info = to_dbs_info(policy->governor_data);
 
-static struct cs_ops cs_ops = {
-	.notifier_block = &cs_cpufreq_notifier_block,
-};
+	dbs_info->down_skip = 0;
+	dbs_info->requested_freq = policy->cur;
+}
 
-static struct common_dbs_data cs_dbs_cdata = {
-	.governor = GOV_CONSERVATIVE,
-	.attr_group_gov_sys = &cs_attr_group_gov_sys,
-	.attr_group_gov_pol = &cs_attr_group_gov_pol,
-	.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 struct dbs_governor cs_governor = {
+	.gov = CPUFREQ_DBS_GOVERNOR_INITIALIZER("conservative"),
+	.kobj_type = { .default_groups = cs_groups },
+	.gov_dbs_update = cs_dbs_update,
+	.alloc = cs_alloc,
+	.free = cs_free,
 	.init = cs_init,
 	.exit = cs_exit,
+	.start = cs_start,
 };
 
-static int cs_cpufreq_governor_dbs(struct cpufreq_policy *policy,
-				   unsigned int event)
-{
-	return cpufreq_governor_dbs(policy, &cs_dbs_cdata, event);
-}
-
-#ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
-static
-#endif
-struct cpufreq_governor cpufreq_gov_conservative = {
-	.name			= "conservative",
-	.governor		= cs_cpufreq_governor_dbs,
-	.max_transition_latency	= TRANSITION_LATENCY_LIMIT,
-	.owner			= THIS_MODULE,
-};
-
-static int __init cpufreq_gov_dbs_init(void)
-{
-	return cpufreq_register_governor(&cpufreq_gov_conservative);
-}
-
-static void __exit cpufreq_gov_dbs_exit(void)
-{
-	cpufreq_unregister_governor(&cpufreq_gov_conservative);
-}
+#define CPU_FREQ_GOV_CONSERVATIVE	(cs_governor.gov)
 
 MODULE_AUTHOR("Alexander Clouter <alex@digriz.org.uk>");
 MODULE_DESCRIPTION("'cpufreq_conservative' - A dynamic cpufreq governor for "
@@ -409,8 +333,11 @@ MODULE_DESCRIPTION("'cpufreq_conservative' - A dynamic cpufreq governor for "
 MODULE_LICENSE("GPL");
 
 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
-fs_initcall(cpufreq_gov_dbs_init);
-#else
-module_init(cpufreq_gov_dbs_init);
+struct cpufreq_governor *cpufreq_default_governor(void)
+{
+	return &CPU_FREQ_GOV_CONSERVATIVE;
+}
 #endif
-module_exit(cpufreq_gov_dbs_exit);
+
+cpufreq_governor_init(CPU_FREQ_GOV_CONSERVATIVE);
+cpufreq_governor_exit(CPU_FREQ_GOV_CONSERVATIVE);