diff options
Diffstat (limited to 'drivers/cpufreq/cpufreq_interactive.c')
-rw-r--r-- | drivers/cpufreq/cpufreq_interactive.c | 993 |
1 files changed, 993 insertions, 0 deletions
diff --git a/drivers/cpufreq/cpufreq_interactive.c b/drivers/cpufreq/cpufreq_interactive.c new file mode 100644 index 00000000000..7953d594449 --- /dev/null +++ b/drivers/cpufreq/cpufreq_interactive.c @@ -0,0 +1,993 @@ +/* + * drivers/cpufreq/cpufreq_interactive.c + * + * Copyright (C) 2010 Google, Inc. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * Author: Mike Chan (mike@android.com) + * + */ + +#include <linux/cpu.h> +#include <linux/cpumask.h> +#include <linux/cpufreq.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/sched.h> +#include <linux/tick.h> +#include <linux/time.h> +#include <linux/timer.h> +#include <linux/workqueue.h> +#include <linux/kthread.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <linux/input.h> +#include <asm/cputime.h> + +#define CREATE_TRACE_POINTS +#include <trace/events/cpufreq_interactive.h> + +static atomic_t active_count = ATOMIC_INIT(0); + +struct cpufreq_interactive_cpuinfo { + struct timer_list cpu_timer; + int timer_idlecancel; + u64 time_in_idle; + u64 idle_exit_time; + u64 timer_run_time; + int idling; + u64 target_set_time; + u64 target_set_time_in_idle; + struct cpufreq_policy *policy; + struct cpufreq_frequency_table *freq_table; + unsigned int target_freq; + unsigned int floor_freq; + u64 floor_validate_time; + int governor_enabled; +}; + +static DEFINE_PER_CPU(struct cpufreq_interactive_cpuinfo, cpuinfo); + +/* Workqueues handle frequency scaling */ +static struct task_struct *up_task; +static struct workqueue_struct *down_wq; +static struct work_struct freq_scale_down_work; +static cpumask_t up_cpumask; +static spinlock_t up_cpumask_lock; +static cpumask_t down_cpumask; +static spinlock_t down_cpumask_lock; +static struct mutex set_speed_lock; + +/* Hi speed to bump to from lo speed when load burst (default max) */ +static u64 hispeed_freq; + +/* Go to hi speed when CPU load at or above this value. */ +#define DEFAULT_GO_HISPEED_LOAD 85 +static unsigned long go_hispeed_load; + +/* + * The minimum amount of time to spend at a frequency before we can ramp down. + */ +#define DEFAULT_MIN_SAMPLE_TIME (80 * USEC_PER_MSEC) +static unsigned long min_sample_time; + +/* + * The sample rate of the timer used to increase frequency + */ +#define DEFAULT_TIMER_RATE (20 * USEC_PER_MSEC) +static unsigned long timer_rate; + +/* + * Wait this long before raising speed above hispeed, by default a single + * timer interval. + */ +#define DEFAULT_ABOVE_HISPEED_DELAY DEFAULT_TIMER_RATE +static unsigned long above_hispeed_delay_val; + +/* + * Boost pulse to hispeed on touchscreen input. + */ + +static int input_boost_val; + +struct cpufreq_interactive_inputopen { + struct input_handle *handle; + struct work_struct inputopen_work; +}; + +static struct cpufreq_interactive_inputopen inputopen; + +/* + * Non-zero means longer-term speed boost active. + */ + +static int boost_val; + +static int cpufreq_governor_interactive(struct cpufreq_policy *policy, + unsigned int event); + +#ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_INTERACTIVE +static +#endif +struct cpufreq_governor cpufreq_gov_interactive = { + .name = "interactive", + .governor = cpufreq_governor_interactive, + .max_transition_latency = 10000000, + .owner = THIS_MODULE, +}; + +static void cpufreq_interactive_timer(unsigned long data) +{ + unsigned int delta_idle; + unsigned int delta_time; + int cpu_load; + int load_since_change; + u64 time_in_idle; + u64 idle_exit_time; + struct cpufreq_interactive_cpuinfo *pcpu = + &per_cpu(cpuinfo, data); + u64 now_idle; + unsigned int new_freq; + unsigned int index; + unsigned long flags; + + smp_rmb(); + + if (!pcpu->governor_enabled) + goto exit; + + /* + * Once pcpu->timer_run_time is updated to >= pcpu->idle_exit_time, + * this lets idle exit know the current idle time sample has + * been processed, and idle exit can generate a new sample and + * re-arm the timer. This prevents a concurrent idle + * exit on that CPU from writing a new set of info at the same time + * the timer function runs (the timer function can't use that info + * until more time passes). + */ + time_in_idle = pcpu->time_in_idle; + idle_exit_time = pcpu->idle_exit_time; + now_idle = get_cpu_idle_time_us(data, &pcpu->timer_run_time); + smp_wmb(); + + /* If we raced with cancelling a timer, skip. */ + if (!idle_exit_time) + goto exit; + + delta_idle = (unsigned int)(now_idle - time_in_idle); + delta_time = (unsigned int)(pcpu->timer_run_time - idle_exit_time); + + /* + * If timer ran less than 1ms after short-term sample started, retry. + */ + if (delta_time < 1000) + goto rearm; + + if (delta_idle > delta_time) + cpu_load = 0; + else + cpu_load = 100 * (delta_time - delta_idle) / delta_time; + + delta_idle = (unsigned int)(now_idle - pcpu->target_set_time_in_idle); + delta_time = (unsigned int)(pcpu->timer_run_time - + pcpu->target_set_time); + + if ((delta_time == 0) || (delta_idle > delta_time)) + load_since_change = 0; + else + load_since_change = + 100 * (delta_time - delta_idle) / delta_time; + + /* + * Choose greater of short-term load (since last idle timer + * started or timer function re-armed itself) or long-term load + * (since last frequency change). + */ + if (load_since_change > cpu_load) + cpu_load = load_since_change; + + if (cpu_load >= go_hispeed_load || boost_val) { + if (pcpu->target_freq <= pcpu->policy->min) { + new_freq = hispeed_freq; + } else { + new_freq = pcpu->policy->max * cpu_load / 100; + + if (new_freq < hispeed_freq) + new_freq = hispeed_freq; + + if (pcpu->target_freq == hispeed_freq && + new_freq > hispeed_freq && + pcpu->timer_run_time - pcpu->target_set_time + < above_hispeed_delay_val) { + trace_cpufreq_interactive_notyet(data, cpu_load, + pcpu->target_freq, + new_freq); + goto rearm; + } + } + } else { + new_freq = pcpu->policy->max * cpu_load / 100; + } + + if (cpufreq_frequency_table_target(pcpu->policy, pcpu->freq_table, + new_freq, CPUFREQ_RELATION_H, + &index)) { + pr_warn_once("timer %d: cpufreq_frequency_table_target error\n", + (int) data); + goto rearm; + } + + new_freq = pcpu->freq_table[index].frequency; + + /* + * Do not scale below floor_freq unless we have been at or above the + * floor frequency for the minimum sample time since last validated. + */ + if (new_freq < pcpu->floor_freq) { + if (pcpu->timer_run_time - pcpu->floor_validate_time + < min_sample_time) { + trace_cpufreq_interactive_notyet(data, cpu_load, + pcpu->target_freq, new_freq); + goto rearm; + } + } + + pcpu->floor_freq = new_freq; + pcpu->floor_validate_time = pcpu->timer_run_time; + + if (pcpu->target_freq == new_freq) { + trace_cpufreq_interactive_already(data, cpu_load, + pcpu->target_freq, new_freq); + goto rearm_if_notmax; + } + + trace_cpufreq_interactive_target(data, cpu_load, pcpu->target_freq, + new_freq); + pcpu->target_set_time_in_idle = now_idle; + pcpu->target_set_time = pcpu->timer_run_time; + + if (new_freq < pcpu->target_freq) { + pcpu->target_freq = new_freq; + spin_lock_irqsave(&down_cpumask_lock, flags); + cpumask_set_cpu(data, &down_cpumask); + spin_unlock_irqrestore(&down_cpumask_lock, flags); + queue_work(down_wq, &freq_scale_down_work); + } else { + pcpu->target_freq = new_freq; + spin_lock_irqsave(&up_cpumask_lock, flags); + cpumask_set_cpu(data, &up_cpumask); + spin_unlock_irqrestore(&up_cpumask_lock, flags); + wake_up_process(up_task); + } + +rearm_if_notmax: + /* + * Already set max speed and don't see a need to change that, + * wait until next idle to re-evaluate, don't need timer. + */ + if (pcpu->target_freq == pcpu->policy->max) + goto exit; + +rearm: + if (!timer_pending(&pcpu->cpu_timer)) { + /* + * If already at min: if that CPU is idle, don't set timer. + * Else cancel the timer if that CPU goes idle. We don't + * need to re-evaluate speed until the next idle exit. + */ + if (pcpu->target_freq == pcpu->policy->min) { + smp_rmb(); + + if (pcpu->idling) + goto exit; + + pcpu->timer_idlecancel = 1; + } + + pcpu->time_in_idle = get_cpu_idle_time_us( + data, &pcpu->idle_exit_time); + mod_timer(&pcpu->cpu_timer, + jiffies + usecs_to_jiffies(timer_rate)); + } + +exit: + return; +} + +static void cpufreq_interactive_idle_start(void) +{ + struct cpufreq_interactive_cpuinfo *pcpu = + &per_cpu(cpuinfo, smp_processor_id()); + int pending; + + if (!pcpu->governor_enabled) + return; + + pcpu->idling = 1; + smp_wmb(); + pending = timer_pending(&pcpu->cpu_timer); + + if (pcpu->target_freq != pcpu->policy->min) { +#ifdef CONFIG_SMP + /* + * Entering idle while not at lowest speed. On some + * platforms this can hold the other CPU(s) at that speed + * even though the CPU is idle. Set a timer to re-evaluate + * speed so this idle CPU doesn't hold the other CPUs above + * min indefinitely. This should probably be a quirk of + * the CPUFreq driver. + */ + if (!pending) { + pcpu->time_in_idle = get_cpu_idle_time_us( + smp_processor_id(), &pcpu->idle_exit_time); + pcpu->timer_idlecancel = 0; + mod_timer(&pcpu->cpu_timer, + jiffies + usecs_to_jiffies(timer_rate)); + } +#endif + } else { + /* + * If at min speed and entering idle after load has + * already been evaluated, and a timer has been set just in + * case the CPU suddenly goes busy, cancel that timer. The + * CPU didn't go busy; we'll recheck things upon idle exit. + */ + if (pending && pcpu->timer_idlecancel) { + del_timer(&pcpu->cpu_timer); + /* + * Ensure last timer run time is after current idle + * sample start time, so next idle exit will always + * start a new idle sampling period. + */ + pcpu->idle_exit_time = 0; + pcpu->timer_idlecancel = 0; + } + } + +} + +static void cpufreq_interactive_idle_end(void) +{ + struct cpufreq_interactive_cpuinfo *pcpu = + &per_cpu(cpuinfo, smp_processor_id()); + + pcpu->idling = 0; + smp_wmb(); + + /* + * Arm the timer for 1-2 ticks later if not already, and if the timer + * function has already processed the previous load sampling + * interval. (If the timer is not pending but has not processed + * the previous interval, it is probably racing with us on another + * CPU. Let it compute load based on the previous sample and then + * re-arm the timer for another interval when it's done, rather + * than updating the interval start time to be "now", which doesn't + * give the timer function enough time to make a decision on this + * run.) + */ + if (timer_pending(&pcpu->cpu_timer) == 0 && + pcpu->timer_run_time >= pcpu->idle_exit_time && + pcpu->governor_enabled) { + pcpu->time_in_idle = + get_cpu_idle_time_us(smp_processor_id(), + &pcpu->idle_exit_time); + pcpu->timer_idlecancel = 0; + mod_timer(&pcpu->cpu_timer, + jiffies + usecs_to_jiffies(timer_rate)); + } + +} + +static int cpufreq_interactive_up_task(void *data) +{ + unsigned int cpu; + cpumask_t tmp_mask; + unsigned long flags; + struct cpufreq_interactive_cpuinfo *pcpu; + + while (1) { + set_current_state(TASK_INTERRUPTIBLE); + spin_lock_irqsave(&up_cpumask_lock, flags); + + if (cpumask_empty(&up_cpumask)) { + spin_unlock_irqrestore(&up_cpumask_lock, flags); + schedule(); + + if (kthread_should_stop()) + break; + + spin_lock_irqsave(&up_cpumask_lock, flags); + } + + set_current_state(TASK_RUNNING); + tmp_mask = up_cpumask; + cpumask_clear(&up_cpumask); + spin_unlock_irqrestore(&up_cpumask_lock, flags); + + for_each_cpu(cpu, &tmp_mask) { + unsigned int j; + unsigned int max_freq = 0; + + pcpu = &per_cpu(cpuinfo, cpu); + smp_rmb(); + + if (!pcpu->governor_enabled) + continue; + + mutex_lock(&set_speed_lock); + + for_each_cpu(j, pcpu->policy->cpus) { + struct cpufreq_interactive_cpuinfo *pjcpu = + &per_cpu(cpuinfo, j); + + if (pjcpu->target_freq > max_freq) + max_freq = pjcpu->target_freq; + } + + if (max_freq != pcpu->policy->cur) + __cpufreq_driver_target(pcpu->policy, + max_freq, + CPUFREQ_RELATION_H); + mutex_unlock(&set_speed_lock); + trace_cpufreq_interactive_up(cpu, pcpu->target_freq, + pcpu->policy->cur); + } + } + + return 0; +} + +static void cpufreq_interactive_freq_down(struct work_struct *work) +{ + unsigned int cpu; + cpumask_t tmp_mask; + unsigned long flags; + struct cpufreq_interactive_cpuinfo *pcpu; + + spin_lock_irqsave(&down_cpumask_lock, flags); + tmp_mask = down_cpumask; + cpumask_clear(&down_cpumask); + spin_unlock_irqrestore(&down_cpumask_lock, flags); + + for_each_cpu(cpu, &tmp_mask) { + unsigned int j; + unsigned int max_freq = 0; + + pcpu = &per_cpu(cpuinfo, cpu); + smp_rmb(); + + if (!pcpu->governor_enabled) + continue; + + mutex_lock(&set_speed_lock); + + for_each_cpu(j, pcpu->policy->cpus) { + struct cpufreq_interactive_cpuinfo *pjcpu = + &per_cpu(cpuinfo, j); + + if (pjcpu->target_freq > max_freq) + max_freq = pjcpu->target_freq; + } + + if (max_freq != pcpu->policy->cur) + __cpufreq_driver_target(pcpu->policy, max_freq, + CPUFREQ_RELATION_H); + + mutex_unlock(&set_speed_lock); + trace_cpufreq_interactive_down(cpu, pcpu->target_freq, + pcpu->policy->cur); + } +} + +static void cpufreq_interactive_boost(void) +{ + int i; + int anyboost = 0; + unsigned long flags; + struct cpufreq_interactive_cpuinfo *pcpu; + + spin_lock_irqsave(&up_cpumask_lock, flags); + + for_each_online_cpu(i) { + pcpu = &per_cpu(cpuinfo, i); + + if (pcpu->target_freq < hispeed_freq) { + pcpu->target_freq = hispeed_freq; + cpumask_set_cpu(i, &up_cpumask); + pcpu->target_set_time_in_idle = + get_cpu_idle_time_us(i, &pcpu->target_set_time); + anyboost = 1; + } + + /* + * Set floor freq and (re)start timer for when last + * validated. + */ + + pcpu->floor_freq = hispeed_freq; + pcpu->floor_validate_time = ktime_to_us(ktime_get()); + } + + spin_unlock_irqrestore(&up_cpumask_lock, flags); + + if (anyboost) + wake_up_process(up_task); +} + +/* + * Pulsed boost on input event raises CPUs to hispeed_freq and lets + * usual algorithm of min_sample_time decide when to allow speed + * to drop. + */ + +static void cpufreq_interactive_input_event(struct input_handle *handle, + unsigned int type, + unsigned int code, int value) +{ + if (input_boost_val && type == EV_SYN && code == SYN_REPORT) { + trace_cpufreq_interactive_boost("input"); + cpufreq_interactive_boost(); + } +} + +static void cpufreq_interactive_input_open(struct work_struct *w) +{ + struct cpufreq_interactive_inputopen *io = + container_of(w, struct cpufreq_interactive_inputopen, + inputopen_work); + int error; + + error = input_open_device(io->handle); + if (error) + input_unregister_handle(io->handle); +} + +static int cpufreq_interactive_input_connect(struct input_handler *handler, + struct input_dev *dev, + const struct input_device_id *id) +{ + struct input_handle *handle; + int error; + + pr_info("%s: connect to %s\n", __func__, dev->name); + handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL); + if (!handle) + return -ENOMEM; + + handle->dev = dev; + handle->handler = handler; + handle->name = "cpufreq_interactive"; + + error = input_register_handle(handle); + if (error) + goto err; + + inputopen.handle = handle; + queue_work(down_wq, &inputopen.inputopen_work); + return 0; +err: + kfree(handle); + return error; +} + +static void cpufreq_interactive_input_disconnect(struct input_handle *handle) +{ + input_close_device(handle); + input_unregister_handle(handle); + kfree(handle); +} + +static const struct input_device_id cpufreq_interactive_ids[] = { + { + .flags = INPUT_DEVICE_ID_MATCH_EVBIT | + INPUT_DEVICE_ID_MATCH_ABSBIT, + .evbit = { BIT_MASK(EV_ABS) }, + .absbit = { [BIT_WORD(ABS_MT_POSITION_X)] = + BIT_MASK(ABS_MT_POSITION_X) | + BIT_MASK(ABS_MT_POSITION_Y) }, + }, /* multi-touch touchscreen */ + { + .flags = INPUT_DEVICE_ID_MATCH_KEYBIT | + INPUT_DEVICE_ID_MATCH_ABSBIT, + .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) }, + .absbit = { [BIT_WORD(ABS_X)] = + BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) }, + }, /* touchpad */ + { }, +}; + +static struct input_handler cpufreq_interactive_input_handler = { + .event = cpufreq_interactive_input_event, + .connect = cpufreq_interactive_input_connect, + .disconnect = cpufreq_interactive_input_disconnect, + .name = "cpufreq_interactive", + .id_table = cpufreq_interactive_ids, +}; + +static ssize_t show_hispeed_freq(struct kobject *kobj, + struct attribute *attr, char *buf) +{ + return sprintf(buf, "%llu\n", hispeed_freq); +} + +static ssize_t store_hispeed_freq(struct kobject *kobj, + struct attribute *attr, const char *buf, + size_t count) +{ + int ret; + u64 val; + + ret = strict_strtoull(buf, 0, &val); + if (ret < 0) + return ret; + hispeed_freq = val; + return count; +} + +static struct global_attr hispeed_freq_attr = __ATTR(hispeed_freq, 0644, + show_hispeed_freq, store_hispeed_freq); + + +static ssize_t show_go_hispeed_load(struct kobject *kobj, + struct attribute *attr, char *buf) +{ + return sprintf(buf, "%lu\n", go_hispeed_load); +} + +static ssize_t store_go_hispeed_load(struct kobject *kobj, + struct attribute *attr, const char *buf, size_t count) +{ + int ret; + unsigned long val; + + ret = strict_strtoul(buf, 0, &val); + if (ret < 0) + return ret; + go_hispeed_load = val; + return count; +} + +static struct global_attr go_hispeed_load_attr = __ATTR(go_hispeed_load, 0644, + show_go_hispeed_load, store_go_hispeed_load); + +static ssize_t show_min_sample_time(struct kobject *kobj, + struct attribute *attr, char *buf) +{ + return sprintf(buf, "%lu\n", min_sample_time); +} + +static ssize_t store_min_sample_time(struct kobject *kobj, + struct attribute *attr, const char *buf, size_t count) +{ + int ret; + unsigned long val; + + ret = strict_strtoul(buf, 0, &val); + if (ret < 0) + return ret; + min_sample_time = val; + return count; +} + +static struct global_attr min_sample_time_attr = __ATTR(min_sample_time, 0644, + show_min_sample_time, store_min_sample_time); + +static ssize_t show_above_hispeed_delay(struct kobject *kobj, + struct attribute *attr, char *buf) +{ + return sprintf(buf, "%lu\n", above_hispeed_delay_val); +} + +static ssize_t store_above_hispeed_delay(struct kobject *kobj, + struct attribute *attr, + const char *buf, size_t count) +{ + int ret; + unsigned long val; + + ret = strict_strtoul(buf, 0, &val); + if (ret < 0) + return ret; + above_hispeed_delay_val = val; + return count; +} + +define_one_global_rw(above_hispeed_delay); + +static ssize_t show_timer_rate(struct kobject *kobj, + struct attribute *attr, char *buf) +{ + return sprintf(buf, "%lu\n", timer_rate); +} + +static ssize_t store_timer_rate(struct kobject *kobj, + struct attribute *attr, const char *buf, size_t count) +{ + int ret; + unsigned long val; + + ret = strict_strtoul(buf, 0, &val); + if (ret < 0) + return ret; + timer_rate = val; + return count; +} + +static struct global_attr timer_rate_attr = __ATTR(timer_rate, 0644, + show_timer_rate, store_timer_rate); + +static ssize_t show_input_boost(struct kobject *kobj, struct attribute *attr, + char *buf) +{ + return sprintf(buf, "%u\n", input_boost_val); +} + +static ssize_t store_input_boost(struct kobject *kobj, struct attribute *attr, + const char *buf, size_t count) +{ + int ret; + unsigned long val; + + ret = strict_strtoul(buf, 0, &val); + if (ret < 0) + return ret; + input_boost_val = val; + return count; +} + +define_one_global_rw(input_boost); + +static ssize_t show_boost(struct kobject *kobj, struct attribute *attr, + char *buf) +{ + return sprintf(buf, "%d\n", boost_val); +} + +static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, + const char *buf, size_t count) +{ + int ret; + unsigned long val; + + ret = kstrtoul(buf, 0, &val); + if (ret < 0) + return ret; + + boost_val = val; + + if (boost_val) { + trace_cpufreq_interactive_boost("on"); + cpufreq_interactive_boost(); + } else { + trace_cpufreq_interactive_unboost("off"); + } + + return count; +} + +define_one_global_rw(boost); + +static ssize_t store_boostpulse(struct kobject *kobj, struct attribute *attr, + const char *buf, size_t count) +{ + int ret; + unsigned long val; + + ret = kstrtoul(buf, 0, &val); + if (ret < 0) + return ret; + + trace_cpufreq_interactive_boost("pulse"); + cpufreq_interactive_boost(); + return count; +} + +static struct global_attr boostpulse = + __ATTR(boostpulse, 0200, NULL, store_boostpulse); + +static struct attribute *interactive_attributes[] = { + &hispeed_freq_attr.attr, + &go_hispeed_load_attr.attr, + &above_hispeed_delay.attr, + &min_sample_time_attr.attr, + &timer_rate_attr.attr, + &input_boost.attr, + &boost.attr, + &boostpulse.attr, + NULL, +}; + +static struct attribute_group interactive_attr_group = { + .attrs = interactive_attributes, + .name = "interactive", +}; + +static int cpufreq_governor_interactive(struct cpufreq_policy *policy, + unsigned int event) +{ + int rc; + unsigned int j; + struct cpufreq_interactive_cpuinfo *pcpu; + struct cpufreq_frequency_table *freq_table; + + switch (event) { + case CPUFREQ_GOV_START: + if (!cpu_online(policy->cpu)) + return -EINVAL; + + freq_table = + cpufreq_frequency_get_table(policy->cpu); + + for_each_cpu(j, policy->cpus) { + pcpu = &per_cpu(cpuinfo, j); + pcpu->policy = policy; + pcpu->target_freq = policy->cur; + pcpu->freq_table = freq_table; + pcpu->target_set_time_in_idle = + get_cpu_idle_time_us(j, + &pcpu->target_set_time); + pcpu->floor_freq = pcpu->target_freq; + pcpu->floor_validate_time = + pcpu->target_set_time; + pcpu->governor_enabled = 1; + smp_wmb(); + } + + if (!hispeed_freq) + hispeed_freq = policy->max; + + /* + * Do not register the idle hook and create sysfs + * entries if we have already done so. + */ + if (atomic_inc_return(&active_count) > 1) + return 0; + + rc = sysfs_create_group(cpufreq_global_kobject, + &interactive_attr_group); + if (rc) + return rc; + + rc = input_register_handler(&cpufreq_interactive_input_handler); + if (rc) + pr_warn("%s: failed to register input handler\n", + __func__); + + break; + + case CPUFREQ_GOV_STOP: + for_each_cpu(j, policy->cpus) { + pcpu = &per_cpu(cpuinfo, j); + pcpu->governor_enabled = 0; + smp_wmb(); + del_timer_sync(&pcpu->cpu_timer); + + /* + * Reset idle exit time since we may cancel the timer + * before it can run after the last idle exit time, + * to avoid tripping the check in idle exit for a timer + * that is trying to run. + */ + pcpu->idle_exit_time = 0; + } + + flush_work(&freq_scale_down_work); + if (atomic_dec_return(&active_count) > 0) + return 0; + + input_unregister_handler(&cpufreq_interactive_input_handler); + sysfs_remove_group(cpufreq_global_kobject, + &interactive_attr_group); + + break; + + case CPUFREQ_GOV_LIMITS: + if (policy->max < policy->cur) + __cpufreq_driver_target(policy, + policy->max, CPUFREQ_RELATION_H); + else if (policy->min > policy->cur) + __cpufreq_driver_target(policy, + policy->min, CPUFREQ_RELATION_L); + break; + } + return 0; +} + +static int cpufreq_interactive_idle_notifier(struct notifier_block *nb, + unsigned long val, + void *data) +{ + switch (val) { + case IDLE_START: + cpufreq_interactive_idle_start(); + break; + case IDLE_END: + cpufreq_interactive_idle_end(); + break; + } + + return 0; +} + +static struct notifier_block cpufreq_interactive_idle_nb = { + .notifier_call = cpufreq_interactive_idle_notifier, +}; + +static int __init cpufreq_interactive_init(void) +{ + unsigned int i; + struct cpufreq_interactive_cpuinfo *pcpu; + struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 }; + + go_hispeed_load = DEFAULT_GO_HISPEED_LOAD; + min_sample_time = DEFAULT_MIN_SAMPLE_TIME; + above_hispeed_delay_val = DEFAULT_ABOVE_HISPEED_DELAY; + timer_rate = DEFAULT_TIMER_RATE; + + /* Initalize per-cpu timers */ + for_each_possible_cpu(i) { + pcpu = &per_cpu(cpuinfo, i); + init_timer(&pcpu->cpu_timer); + pcpu->cpu_timer.function = cpufreq_interactive_timer; + pcpu->cpu_timer.data = i; + } + + up_task = kthread_create(cpufreq_interactive_up_task, NULL, + "kinteractiveup"); + if (IS_ERR(up_task)) + return PTR_ERR(up_task); + + sched_setscheduler_nocheck(up_task, SCHED_FIFO, ¶m); + get_task_struct(up_task); + + /* No rescuer thread, bind to CPU queuing the work for possibly + warm cache (probably doesn't matter much). */ + down_wq = alloc_workqueue("knteractive_down", 0, 1); + + if (!down_wq) + goto err_freeuptask; + + INIT_WORK(&freq_scale_down_work, + cpufreq_interactive_freq_down); + + spin_lock_init(&up_cpumask_lock); + spin_lock_init(&down_cpumask_lock); + mutex_init(&set_speed_lock); + + idle_notifier_register(&cpufreq_interactive_idle_nb); + INIT_WORK(&inputopen.inputopen_work, cpufreq_interactive_input_open); + return cpufreq_register_governor(&cpufreq_gov_interactive); + +err_freeuptask: + put_task_struct(up_task); + return -ENOMEM; +} + +#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_INTERACTIVE +fs_initcall(cpufreq_interactive_init); +#else +module_init(cpufreq_interactive_init); +#endif + +static void __exit cpufreq_interactive_exit(void) +{ + cpufreq_unregister_governor(&cpufreq_gov_interactive); + kthread_stop(up_task); + put_task_struct(up_task); + destroy_workqueue(down_wq); +} + +module_exit(cpufreq_interactive_exit); + +MODULE_AUTHOR("Mike Chan <mike@android.com>"); +MODULE_DESCRIPTION("'cpufreq_interactive' - A cpufreq governor for " + "Latency sensitive workloads"); +MODULE_LICENSE("GPL"); |