[CPUFREQ] conservative: fixup governor to function more like ondemand logic (8e677ce8) · Commits · 戴 / test

drivers/cpufreq/cpufreq_conservative.c

+188 −140

Original line number	Original line	Diff line number	Diff line
	@@ -13,22 +13,17 @@

	#include <linux/kernel.h>		#include <linux/kernel.h>
	#include <linux/module.h>		#include <linux/module.h>
	#include <linux/smp.h>
	#include <linux/init.h>		#include <linux/init.h>
	#include <linux/interrupt.h>
	#include <linux/ctype.h>
	#include <linux/cpufreq.h>		#include <linux/cpufreq.h>
	#include <linux/sysctl.h>
	#include <linux/types.h>
	#include <linux/fs.h>
	#include <linux/sysfs.h>
	#include <linux/cpu.h>		#include <linux/cpu.h>
	#include <linux/kmod.h>
	#include <linux/workqueue.h>
	#include <linux/jiffies.h>		#include <linux/jiffies.h>
	#include <linux/kernel_stat.h>		#include <linux/kernel_stat.h>
	#include <linux/percpu.h>
	#include <linux/mutex.h>		#include <linux/mutex.h>
			#include <linux/hrtimer.h>
			#include <linux/tick.h>
			#include <linux/ktime.h>
			#include <linux/sched.h>

	/*		/*
	* dbs is used in this file as a shortform for demandbased switching		* dbs is used in this file as a shortform for demandbased switching
	* It helps to keep variable names smaller, simpler		* It helps to keep variable names smaller, simpler
	@@ -43,8 +38,8 @@
	* latency of the processor. The governor will work on any processor with		* latency of the processor. The governor will work on any processor with
	* transition latency <= 10mS, using appropriate sampling		* transition latency <= 10mS, using appropriate sampling
	* rate.		* rate.
	* For CPUs with transition latency > 10mS (mostly drivers		* For CPUs with transition latency > 10mS (mostly drivers with CPUFREQ_ETERNAL)
	* with CPUFREQ_ETERNAL), this governor will not work.		* this governor will not work.
	* All times here are in uS.		* All times here are in uS.
	*/		*/
	static unsigned int def_sampling_rate;		static unsigned int def_sampling_rate;
	@@ -75,12 +70,15 @@ static unsigned int minimum_sampling_rate(void)
	static void do_dbs_timer(struct work_struct *work);		static void do_dbs_timer(struct work_struct *work);

	struct cpu_dbs_info_s {		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 cpufreq_policy *cur_policy;
	unsigned int prev_cpu_idle_up;		struct delayed_work work;
	unsigned int prev_cpu_idle_down;
	unsigned int enable;
	unsigned int down_skip;		unsigned int down_skip;
	unsigned int requested_freq;		unsigned int requested_freq;
			int cpu;
			unsigned int enable:1;
	};		};
	static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info);		static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info);

	@@ -95,18 +93,17 @@ static unsigned int dbs_enable; /* number of CPUs using this policy */
	* is recursive for the same process. -Venki		* is recursive for the same process. -Venki
	*/		*/
	static DEFINE_MUTEX(dbs_mutex);		static DEFINE_MUTEX(dbs_mutex);
	static DECLARE_DELAYED_WORK(dbs_work, do_dbs_timer);

	struct dbs_tuners {		static struct workqueue_struct *kconservative_wq;

			static struct dbs_tuners {
	unsigned int sampling_rate;		unsigned int sampling_rate;
	unsigned int sampling_down_factor;		unsigned int sampling_down_factor;
	unsigned int up_threshold;		unsigned int up_threshold;
	unsigned int down_threshold;		unsigned int down_threshold;
	unsigned int ignore_nice;		unsigned int ignore_nice;
	unsigned int freq_step;		unsigned int freq_step;
	};		} dbs_tuners_ins = {

	static struct dbs_tuners dbs_tuners_ins = {
	.up_threshold = DEF_FREQUENCY_UP_THRESHOLD,		.up_threshold = DEF_FREQUENCY_UP_THRESHOLD,
	.down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD,		.down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD,
	.sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR,		.sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR,
	@@ -114,18 +111,37 @@ static struct dbs_tuners dbs_tuners_ins = {
	.freq_step = 5,		.freq_step = 5,
	};		};

	static inline unsigned int get_cpu_idle_time(unsigned int cpu)		static inline cputime64_t get_cpu_idle_time_jiffy(unsigned int cpu,
			cputime64_t *wall)
	{		{
	unsigned int add_nice = 0, ret;		cputime64_t idle_time;
			cputime64_t cur_wall_time;
			cputime64_t busy_time;

	if (dbs_tuners_ins.ignore_nice)		cur_wall_time = jiffies64_to_cputime64(get_jiffies_64());
	add_nice = kstat_cpu(cpu).cpustat.nice;		busy_time = cputime64_add(kstat_cpu(cpu).cpustat.user,
			kstat_cpu(cpu).cpustat.system);

			busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.irq);
			busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.softirq);
			busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.steal);
			busy_time = cputime64_add(busy_time, kstat_cpu(cpu).cpustat.nice);

			idle_time = cputime64_sub(cur_wall_time, busy_time);
			if (wall)
			*wall = cur_wall_time;

			return idle_time;
			}

			static inline cputime64_t get_cpu_idle_time(unsigned int cpu, cputime64_t *wall)
			{
			u64 idle_time = get_cpu_idle_time_us(cpu, wall);

	ret = kstat_cpu(cpu).cpustat.idle +		if (idle_time == -1ULL)
	kstat_cpu(cpu).cpustat.iowait +		return get_cpu_idle_time_jiffy(cpu, wall);
	add_nice;

	return ret;		return idle_time;
	}		}

	/* keep track of frequency transitions */		/* keep track of frequency transitions */
	@@ -213,6 +229,7 @@ static ssize_t store_sampling_down_factor(struct cpufreq_policy *unused,
	unsigned int input;		unsigned int input;
	int ret;		int ret;
	ret = sscanf(buf, "%u", &input);		ret = sscanf(buf, "%u", &input);

	if (ret != 1 \|\| input > MAX_SAMPLING_DOWN_FACTOR \|\| input < 1)		if (ret != 1 \|\| input > MAX_SAMPLING_DOWN_FACTOR \|\| input < 1)
	return -EINVAL;		return -EINVAL;

	@@ -230,11 +247,10 @@ static ssize_t store_sampling_rate(struct cpufreq_policy *unused,
	int ret;		int ret;
	ret = sscanf(buf, "%u", &input);		ret = sscanf(buf, "%u", &input);

	mutex_lock(&dbs_mutex);		if (ret != 1)
	if (ret != 1) {
	mutex_unlock(&dbs_mutex);
	return -EINVAL;		return -EINVAL;
	}
			mutex_lock(&dbs_mutex);
	dbs_tuners_ins.sampling_rate = max(input, minimum_sampling_rate());		dbs_tuners_ins.sampling_rate = max(input, minimum_sampling_rate());
	mutex_unlock(&dbs_mutex);		mutex_unlock(&dbs_mutex);

	@@ -269,7 +285,9 @@ static ssize_t store_down_threshold(struct cpufreq_policy *unused,
	ret = sscanf(buf, "%u", &input);		ret = sscanf(buf, "%u", &input);

	mutex_lock(&dbs_mutex);		mutex_lock(&dbs_mutex);
	if (ret != 1 \|\| input > 100 \|\| input >= dbs_tuners_ins.up_threshold) {		/* cannot be lower than 11 otherwise freq will not fall */
			if (ret != 1 \|\| input < 11 \|\| input > 100 \|\|
			input >= dbs_tuners_ins.up_threshold) {
	mutex_unlock(&dbs_mutex);		mutex_unlock(&dbs_mutex);
	return -EINVAL;		return -EINVAL;
	}		}
	@@ -302,12 +320,14 @@ static ssize_t store_ignore_nice_load(struct cpufreq_policy *policy,
	}		}
	dbs_tuners_ins.ignore_nice = input;		dbs_tuners_ins.ignore_nice = input;

	/* we need to re-evaluate prev_cpu_idle_up and prev_cpu_idle_down */		/* we need to re-evaluate prev_cpu_idle */
	for_each_online_cpu(j) {		for_each_online_cpu(j) {
	struct cpu_dbs_info_s *j_dbs_info;		struct cpu_dbs_info_s *dbs_info;
	j_dbs_info = &per_cpu(cpu_dbs_info, j);		dbs_info = &per_cpu(cpu_dbs_info, j);
	j_dbs_info->prev_cpu_idle_up = get_cpu_idle_time(j);		dbs_info->prev_cpu_idle = get_cpu_idle_time(j,
	j_dbs_info->prev_cpu_idle_down = j_dbs_info->prev_cpu_idle_up;		&dbs_info->prev_cpu_wall);
			if (dbs_tuners_ins.ignore_nice)
			dbs_info->prev_cpu_nice = kstat_cpu(j).cpustat.nice;
	}		}
	mutex_unlock(&dbs_mutex);		mutex_unlock(&dbs_mutex);

	@@ -319,7 +339,6 @@ static ssize_t store_freq_step(struct cpufreq_policy *policy,
	{		{
	unsigned int input;		unsigned int input;
	int ret;		int ret;

	ret = sscanf(buf, "%u", &input);		ret = sscanf(buf, "%u", &input);

	if (ret != 1)		if (ret != 1)
	@@ -367,55 +386,78 @@ static struct attribute_group dbs_attr_group = {

	/************************ sysfs end **********************/		/************************ sysfs end **********************/

	static void dbs_check_cpu(int cpu)		static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
	{		{
	unsigned int idle_ticks, up_idle_ticks, down_idle_ticks;		unsigned int load = 0;
	unsigned int tmp_idle_ticks, total_idle_ticks;
	unsigned int freq_target;		unsigned int freq_target;
	unsigned int freq_down_sampling_rate;
	struct cpu_dbs_info_s *this_dbs_info = &per_cpu(cpu_dbs_info, cpu);
	struct cpufreq_policy *policy;

	if (!this_dbs_info->enable)		struct cpufreq_policy *policy;
	return;		unsigned int j;

	policy = this_dbs_info->cur_policy;		policy = this_dbs_info->cur_policy;

	/*		/*
	* The default safe range is 20% to 80%		* Every sampling_rate, we check, if current idle time is less
	* Every sampling_rate, we check		* than 20% (default), then we try to increase frequency
	* - If current idle time is less than 20%, then we try to		* Every sampling_rate*sampling_down_factor, we check, if current
	* increase frequency		* idle time is more than 80%, then we try to decrease 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.		* Any frequency increase takes it to the maximum frequency.
	* Frequency reduction happens at minimum steps of		* Frequency reduction happens at minimum steps of
	* 5% (default) of max_frequency		* 5% (default) of maximum frequency
	*/		*/

	/* Check for frequency increase */		/* Get Absolute Load */
	idle_ticks = UINT_MAX;		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;

	/* Check for frequency increase */		j_dbs_info = &per_cpu(cpu_dbs_info, j);
	total_idle_ticks = get_cpu_idle_time(cpu);
	tmp_idle_ticks = total_idle_ticks -		cur_idle_time = get_cpu_idle_time(j, &cur_wall_time);
	this_dbs_info->prev_cpu_idle_up;
	this_dbs_info->prev_cpu_idle_up = total_idle_ticks;

	if (tmp_idle_ticks < idle_ticks)		wall_time = (unsigned int) cputime64_sub(cur_wall_time,
	idle_ticks = tmp_idle_ticks;		j_dbs_info->prev_cpu_wall);
			j_dbs_info->prev_cpu_wall = cur_wall_time;

	/* Scale idle ticks by 100 and compare with up and down ticks */		idle_time = (unsigned int) cputime64_sub(cur_idle_time,
	idle_ticks *= 100;		j_dbs_info->prev_cpu_idle);
	up_idle_ticks = (100 - dbs_tuners_ins.up_threshold) *		j_dbs_info->prev_cpu_idle = cur_idle_time;
	usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
			if (dbs_tuners_ins.ignore_nice) {
			cputime64_t cur_nice;
			unsigned long cur_nice_jiffies;

			cur_nice = cputime64_sub(kstat_cpu(j).cpustat.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 = kstat_cpu(j).cpustat.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;
			}

			/*
			* 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;

	if (idle_ticks < up_idle_ticks) {		/* Check for frequency increase */
			if (load > dbs_tuners_ins.up_threshold) {
	this_dbs_info->down_skip = 0;		this_dbs_info->down_skip = 0;
	this_dbs_info->prev_cpu_idle_down =
	this_dbs_info->prev_cpu_idle_up;

	/* if we are already at full speed then break out early */		/* if we are already at full speed then break out early */
	if (this_dbs_info->requested_freq == policy->max)		if (this_dbs_info->requested_freq == policy->max)
	@@ -436,49 +478,24 @@ static void dbs_check_cpu(int cpu)
	return;		return;
	}		}

	/* Check for frequency decrease */
	this_dbs_info->down_skip++;
	if (this_dbs_info->down_skip < dbs_tuners_ins.sampling_down_factor)
	return;

	/* Check for frequency decrease */
	total_idle_ticks = this_dbs_info->prev_cpu_idle_up;
	tmp_idle_ticks = total_idle_ticks -
	this_dbs_info->prev_cpu_idle_down;
	this_dbs_info->prev_cpu_idle_down = total_idle_ticks;

	if (tmp_idle_ticks < idle_ticks)
	idle_ticks = tmp_idle_ticks;

	/* Scale idle ticks by 100 and compare with up and down ticks */
	idle_ticks *= 100;
	this_dbs_info->down_skip = 0;

	freq_down_sampling_rate = dbs_tuners_ins.sampling_rate *
	dbs_tuners_ins.sampling_down_factor;
	down_idle_ticks = (100 - dbs_tuners_ins.down_threshold) *
	usecs_to_jiffies(freq_down_sampling_rate);

	if (idle_ticks > down_idle_ticks) {
	/*		/*
	* if we are already at the lowest speed then break out early		* The optimal frequency is the frequency that is the lowest that
	* or if we 'cannot' reduce the speed as the user might want		* can support the current CPU usage without triggering the up
	* freq_target to be zero		* policy. To be safe, we focus 10 points under the threshold.
	*/		*/
	if (this_dbs_info->requested_freq == policy->min		if (load < (dbs_tuners_ins.down_threshold - 10)) {
	\|\| dbs_tuners_ins.freq_step == 0)
	return;

	freq_target = (dbs_tuners_ins.freq_step * policy->max) / 100;		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;		this_dbs_info->requested_freq -= freq_target;
	if (this_dbs_info->requested_freq < policy->min)		if (this_dbs_info->requested_freq < policy->min)
	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_driver_target(policy, this_dbs_info->requested_freq,
	CPUFREQ_RELATION_H);		CPUFREQ_RELATION_H);
	return;		return;
	@@ -487,27 +504,45 @@ static void dbs_check_cpu(int cpu)

	static void do_dbs_timer(struct work_struct *work)		static void do_dbs_timer(struct work_struct *work)
	{		{
	int i;		struct cpu_dbs_info_s *dbs_info =
	mutex_lock(&dbs_mutex);		container_of(work, struct cpu_dbs_info_s, work.work);
	for_each_online_cpu(i)		unsigned int cpu = dbs_info->cpu;
	dbs_check_cpu(i);
	schedule_delayed_work(&dbs_work,		/* We want all CPUs to do sampling nearly on same jiffy */
	usecs_to_jiffies(dbs_tuners_ins.sampling_rate));		int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
	mutex_unlock(&dbs_mutex);
			delay -= jiffies % delay;

			if (lock_policy_rwsem_write(cpu) < 0)
			return;

			if (!dbs_info->enable) {
			unlock_policy_rwsem_write(cpu);
			return;
	}		}

	static inline void dbs_timer_init(void)		dbs_check_cpu(dbs_info);

			queue_delayed_work_on(cpu, kconservative_wq, &dbs_info->work, delay);
			unlock_policy_rwsem_write(cpu);
			}

			static inline void dbs_timer_init(struct cpu_dbs_info_s *dbs_info)
	{		{
	init_timer_deferrable(&dbs_work.timer);		/* We want all CPUs to do sampling nearly on same jiffy */
	schedule_delayed_work(&dbs_work,		int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
	usecs_to_jiffies(dbs_tuners_ins.sampling_rate));		delay -= jiffies % delay;
	return;
			dbs_info->enable = 1;
			INIT_DELAYED_WORK_DEFERRABLE(&dbs_info->work, do_dbs_timer);
			queue_delayed_work_on(dbs_info->cpu, kconservative_wq, &dbs_info->work,
			delay);
	}		}

	static inline void dbs_timer_exit(void)		static inline void dbs_timer_exit(struct cpu_dbs_info_s *dbs_info)
	{		{
	cancel_delayed_work(&dbs_work);		dbs_info->enable = 0;
	return;		cancel_delayed_work(&dbs_info->work);
	}		}

	static int cpufreq_governor_dbs(struct cpufreq_policy *policy,		static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
	@@ -541,11 +576,13 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
	j_dbs_info = &per_cpu(cpu_dbs_info, j);		j_dbs_info = &per_cpu(cpu_dbs_info, j);
	j_dbs_info->cur_policy = policy;		j_dbs_info->cur_policy = policy;

	j_dbs_info->prev_cpu_idle_up = get_cpu_idle_time(cpu);		j_dbs_info->prev_cpu_idle = get_cpu_idle_time(j,
	j_dbs_info->prev_cpu_idle_down		&j_dbs_info->prev_cpu_wall);
	= j_dbs_info->prev_cpu_idle_up;		if (dbs_tuners_ins.ignore_nice) {
			j_dbs_info->prev_cpu_nice =
			kstat_cpu(j).cpustat.nice;
			}
	}		}
	this_dbs_info->enable = 1;
	this_dbs_info->down_skip = 0;		this_dbs_info->down_skip = 0;
	this_dbs_info->requested_freq = policy->cur;		this_dbs_info->requested_freq = policy->cur;

	@@ -567,30 +604,30 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,

	dbs_tuners_ins.sampling_rate = def_sampling_rate;		dbs_tuners_ins.sampling_rate = def_sampling_rate;

	dbs_timer_init();
	cpufreq_register_notifier(		cpufreq_register_notifier(
	&dbs_cpufreq_notifier_block,		&dbs_cpufreq_notifier_block,
	CPUFREQ_TRANSITION_NOTIFIER);		CPUFREQ_TRANSITION_NOTIFIER);
	}		}
			dbs_timer_init(this_dbs_info);

	mutex_unlock(&dbs_mutex);		mutex_unlock(&dbs_mutex);

	break;		break;

	case CPUFREQ_GOV_STOP:		case CPUFREQ_GOV_STOP:
	mutex_lock(&dbs_mutex);		mutex_lock(&dbs_mutex);
	this_dbs_info->enable = 0;		dbs_timer_exit(this_dbs_info);
	sysfs_remove_group(&policy->kobj, &dbs_attr_group);		sysfs_remove_group(&policy->kobj, &dbs_attr_group);
	dbs_enable--;		dbs_enable--;

	/*		/*
	* Stop the timerschedule work, when this governor		* Stop the timerschedule work, when this governor
	* is used for first time		* is used for first time
	*/		*/
	if (dbs_enable == 0) {		if (dbs_enable == 0)
	dbs_timer_exit();
	cpufreq_unregister_notifier(		cpufreq_unregister_notifier(
	&dbs_cpufreq_notifier_block,		&dbs_cpufreq_notifier_block,
	CPUFREQ_TRANSITION_NOTIFIER);		CPUFREQ_TRANSITION_NOTIFIER);
	}

	mutex_unlock(&dbs_mutex);		mutex_unlock(&dbs_mutex);

	@@ -607,6 +644,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
	this_dbs_info->cur_policy,		this_dbs_info->cur_policy,
	policy->min, CPUFREQ_RELATION_L);		policy->min, CPUFREQ_RELATION_L);
	mutex_unlock(&dbs_mutex);		mutex_unlock(&dbs_mutex);

	break;		break;
	}		}
	return 0;		return 0;
	@@ -624,15 +662,25 @@ struct cpufreq_governor cpufreq_gov_conservative = {

	static int __init cpufreq_gov_dbs_init(void)		static int __init cpufreq_gov_dbs_init(void)
	{		{
	return cpufreq_register_governor(&cpufreq_gov_conservative);		int err;

			kconservative_wq = create_workqueue("kconservative");
			if (!kconservative_wq) {
			printk(KERN_ERR "Creation of kconservative failed\n");
			return -EFAULT;
			}

			err = cpufreq_register_governor(&cpufreq_gov_conservative);
			if (err)
			destroy_workqueue(kconservative_wq);

			return err;
	}		}

	static void __exit cpufreq_gov_dbs_exit(void)		static void __exit cpufreq_gov_dbs_exit(void)
	{		{
	/* Make sure that the scheduled work is indeed not running */
	flush_scheduled_work();

	cpufreq_unregister_governor(&cpufreq_gov_conservative);		cpufreq_unregister_governor(&cpufreq_gov_conservative);
			destroy_workqueue(kconservative_wq);
	}		}

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