| /* Copyright (c) 2010-2012, Code Aurora Forum. All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 and |
| * only version 2 as published by the Free Software Foundation. |
| * |
| * 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. |
| * |
| */ |
| /* |
| * Qualcomm MSM Runqueue Stats and cpu utilization Interface for Userspace |
| */ |
| #include <linux/kernel.h> |
| #include <linux/init.h> |
| #include <linux/module.h> |
| #include <linux/hrtimer.h> |
| #include <linux/cpu.h> |
| #include <linux/kobject.h> |
| #include <linux/sysfs.h> |
| #include <linux/notifier.h> |
| #include <linux/slab.h> |
| #include <linux/workqueue.h> |
| #include <linux/sched.h> |
| #include <linux/spinlock.h> |
| #include <linux/rq_stats.h> |
| #include <linux/cpufreq.h> |
| #include <linux/kernel_stat.h> |
| #include <linux/tick.h> |
| #include <asm/smp_plat.h> |
| |
| #define MAX_LONG_SIZE 24 |
| #define DEFAULT_RQ_POLL_JIFFIES 1 |
| #define DEFAULT_DEF_TIMER_JIFFIES 5 |
| |
| struct notifier_block freq_transition; |
| struct notifier_block cpu_hotplug; |
| |
| struct cpu_load_data { |
| cputime64_t prev_cpu_idle; |
| cputime64_t prev_cpu_wall; |
| cputime64_t prev_cpu_iowait; |
| unsigned int avg_load_maxfreq; |
| unsigned int samples; |
| unsigned int window_size; |
| unsigned int cur_freq; |
| unsigned int policy_max; |
| cpumask_var_t related_cpus; |
| struct mutex cpu_load_mutex; |
| }; |
| |
| static DEFINE_PER_CPU(struct cpu_load_data, cpuload); |
| |
| static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
| { |
| u64 idle_time; |
| u64 cur_wall_time; |
| u64 busy_time; |
| |
| cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); |
| |
| busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; |
| busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; |
| busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; |
| busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; |
| busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; |
| busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; |
| |
| idle_time = cur_wall_time - busy_time; |
| if (wall) |
| *wall = jiffies_to_usecs(cur_wall_time); |
| |
| return jiffies_to_usecs(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, NULL); |
| |
| if (idle_time == -1ULL) |
| return get_cpu_idle_time_jiffy(cpu, wall); |
| else |
| idle_time += get_cpu_iowait_time_us(cpu, wall); |
| |
| return idle_time; |
| } |
| |
| static inline cputime64_t get_cpu_iowait_time(unsigned int cpu, |
| cputime64_t *wall) |
| { |
| u64 iowait_time = get_cpu_iowait_time_us(cpu, wall); |
| |
| if (iowait_time == -1ULL) |
| return 0; |
| |
| return iowait_time; |
| } |
| |
| static int update_average_load(unsigned int freq, unsigned int cpu) |
| { |
| |
| struct cpu_load_data *pcpu = &per_cpu(cpuload, cpu); |
| cputime64_t cur_wall_time, cur_idle_time, cur_iowait_time; |
| unsigned int idle_time, wall_time, iowait_time; |
| unsigned int cur_load, load_at_max_freq; |
| |
| cur_idle_time = get_cpu_idle_time(cpu, &cur_wall_time); |
| cur_iowait_time = get_cpu_iowait_time(cpu, &cur_wall_time); |
| |
| wall_time = (unsigned int) (cur_wall_time - pcpu->prev_cpu_wall); |
| pcpu->prev_cpu_wall = cur_wall_time; |
| |
| idle_time = (unsigned int) (cur_idle_time - pcpu->prev_cpu_idle); |
| pcpu->prev_cpu_idle = cur_idle_time; |
| |
| iowait_time = (unsigned int) (cur_iowait_time - pcpu->prev_cpu_iowait); |
| pcpu->prev_cpu_iowait = cur_iowait_time; |
| |
| if (idle_time >= iowait_time) |
| idle_time -= iowait_time; |
| |
| if (unlikely(!wall_time || wall_time < idle_time)) |
| return 0; |
| |
| cur_load = 100 * (wall_time - idle_time) / wall_time; |
| |
| /* Calculate the scaled load across CPU */ |
| load_at_max_freq = (cur_load * freq) / pcpu->policy_max; |
| |
| if (!pcpu->avg_load_maxfreq) { |
| /* This is the first sample in this window*/ |
| pcpu->avg_load_maxfreq = load_at_max_freq; |
| pcpu->window_size = wall_time; |
| } else { |
| /* |
| * The is already a sample available in this window. |
| * Compute weighted average with prev entry, so that we get |
| * the precise weighted load. |
| */ |
| pcpu->avg_load_maxfreq = |
| ((pcpu->avg_load_maxfreq * pcpu->window_size) + |
| (load_at_max_freq * wall_time)) / |
| (wall_time + pcpu->window_size); |
| |
| pcpu->window_size += wall_time; |
| } |
| |
| return 0; |
| } |
| |
| static unsigned int report_load_at_max_freq(void) |
| { |
| int cpu; |
| struct cpu_load_data *pcpu; |
| unsigned int total_load = 0; |
| |
| for_each_online_cpu(cpu) { |
| pcpu = &per_cpu(cpuload, cpu); |
| mutex_lock(&pcpu->cpu_load_mutex); |
| update_average_load(pcpu->cur_freq, cpu); |
| total_load += pcpu->avg_load_maxfreq; |
| pcpu->avg_load_maxfreq = 0; |
| mutex_unlock(&pcpu->cpu_load_mutex); |
| } |
| return total_load; |
| } |
| |
| static int cpufreq_transition_handler(struct notifier_block *nb, |
| unsigned long val, void *data) |
| { |
| struct cpufreq_freqs *freqs = data; |
| struct cpu_load_data *this_cpu = &per_cpu(cpuload, freqs->cpu); |
| int j; |
| |
| switch (val) { |
| case CPUFREQ_POSTCHANGE: |
| for_each_cpu(j, this_cpu->related_cpus) { |
| struct cpu_load_data *pcpu = &per_cpu(cpuload, j); |
| mutex_lock(&pcpu->cpu_load_mutex); |
| update_average_load(freqs->old, freqs->cpu); |
| pcpu->cur_freq = freqs->new; |
| mutex_unlock(&pcpu->cpu_load_mutex); |
| } |
| break; |
| } |
| return 0; |
| } |
| |
| static int cpu_hotplug_handler(struct notifier_block *nb, |
| unsigned long val, void *data) |
| { |
| unsigned int cpu = (unsigned long)data; |
| struct cpu_load_data *this_cpu = &per_cpu(cpuload, cpu); |
| |
| switch (val) { |
| case CPU_ONLINE: |
| case CPU_ONLINE_FROZEN: |
| this_cpu->avg_load_maxfreq = 0; |
| } |
| |
| return NOTIFY_OK; |
| } |
| |
| static void def_work_fn(struct work_struct *work) |
| { |
| int64_t diff; |
| |
| diff = ktime_to_ns(ktime_get()) - rq_info.def_start_time; |
| do_div(diff, 1000 * 1000); |
| rq_info.def_interval = (unsigned int) diff; |
| |
| /* Notify polling threads on change of value */ |
| sysfs_notify(rq_info.kobj, NULL, "def_timer_ms"); |
| } |
| |
| static ssize_t run_queue_avg_show(struct kobject *kobj, |
| struct kobj_attribute *attr, char *buf) |
| { |
| unsigned int val = 0; |
| unsigned long flags = 0; |
| |
| spin_lock_irqsave(&rq_lock, flags); |
| /* rq avg currently available only on one core */ |
| val = rq_info.rq_avg; |
| rq_info.rq_avg = 0; |
| spin_unlock_irqrestore(&rq_lock, flags); |
| |
| return snprintf(buf, PAGE_SIZE, "%d.%d\n", val/10, val%10); |
| } |
| |
| static struct kobj_attribute run_queue_avg_attr = __ATTR_RO(run_queue_avg); |
| |
| static ssize_t show_run_queue_poll_ms(struct kobject *kobj, |
| struct kobj_attribute *attr, char *buf) |
| { |
| int ret = 0; |
| unsigned long flags = 0; |
| |
| spin_lock_irqsave(&rq_lock, flags); |
| ret = snprintf(buf, MAX_LONG_SIZE, "%u\n", |
| jiffies_to_msecs(rq_info.rq_poll_jiffies)); |
| spin_unlock_irqrestore(&rq_lock, flags); |
| |
| return ret; |
| } |
| |
| static ssize_t store_run_queue_poll_ms(struct kobject *kobj, |
| struct kobj_attribute *attr, |
| const char *buf, size_t count) |
| { |
| unsigned int val = 0; |
| unsigned long flags = 0; |
| static DEFINE_MUTEX(lock_poll_ms); |
| |
| mutex_lock(&lock_poll_ms); |
| |
| spin_lock_irqsave(&rq_lock, flags); |
| sscanf(buf, "%u", &val); |
| rq_info.rq_poll_jiffies = msecs_to_jiffies(val); |
| spin_unlock_irqrestore(&rq_lock, flags); |
| |
| mutex_unlock(&lock_poll_ms); |
| |
| return count; |
| } |
| |
| static struct kobj_attribute run_queue_poll_ms_attr = |
| __ATTR(run_queue_poll_ms, S_IWUSR | S_IRUSR, show_run_queue_poll_ms, |
| store_run_queue_poll_ms); |
| |
| static ssize_t show_def_timer_ms(struct kobject *kobj, |
| struct kobj_attribute *attr, char *buf) |
| { |
| return snprintf(buf, MAX_LONG_SIZE, "%u\n", rq_info.def_interval); |
| } |
| |
| static ssize_t store_def_timer_ms(struct kobject *kobj, |
| struct kobj_attribute *attr, const char *buf, size_t count) |
| { |
| unsigned int val = 0; |
| |
| sscanf(buf, "%u", &val); |
| rq_info.def_timer_jiffies = msecs_to_jiffies(val); |
| |
| rq_info.def_start_time = ktime_to_ns(ktime_get()); |
| return count; |
| } |
| |
| static struct kobj_attribute def_timer_ms_attr = |
| __ATTR(def_timer_ms, S_IWUSR | S_IRUSR, show_def_timer_ms, |
| store_def_timer_ms); |
| |
| static ssize_t show_cpu_normalized_load(struct kobject *kobj, |
| struct kobj_attribute *attr, char *buf) |
| { |
| return snprintf(buf, MAX_LONG_SIZE, "%u\n", report_load_at_max_freq()); |
| } |
| |
| static struct kobj_attribute cpu_normalized_load_attr = |
| __ATTR(cpu_normalized_load, S_IWUSR | S_IRUSR, show_cpu_normalized_load, |
| NULL); |
| |
| static struct attribute *rq_attrs[] = { |
| &cpu_normalized_load_attr.attr, |
| &def_timer_ms_attr.attr, |
| &run_queue_avg_attr.attr, |
| &run_queue_poll_ms_attr.attr, |
| NULL, |
| }; |
| |
| static struct attribute_group rq_attr_group = { |
| .attrs = rq_attrs, |
| }; |
| |
| static int init_rq_attribs(void) |
| { |
| int err; |
| |
| rq_info.rq_avg = 0; |
| rq_info.attr_group = &rq_attr_group; |
| |
| /* Create /sys/devices/system/cpu/cpu0/rq-stats/... */ |
| rq_info.kobj = kobject_create_and_add("rq-stats", |
| &get_cpu_device(0)->kobj); |
| if (!rq_info.kobj) |
| return -ENOMEM; |
| |
| err = sysfs_create_group(rq_info.kobj, rq_info.attr_group); |
| if (err) |
| kobject_put(rq_info.kobj); |
| else |
| kobject_uevent(rq_info.kobj, KOBJ_ADD); |
| |
| return err; |
| } |
| |
| static int __init msm_rq_stats_init(void) |
| { |
| int ret; |
| int i; |
| struct cpufreq_policy cpu_policy; |
| /* Bail out if this is not an SMP Target */ |
| if (!is_smp()) { |
| rq_info.init = 0; |
| return -ENOSYS; |
| } |
| |
| rq_wq = create_singlethread_workqueue("rq_stats"); |
| BUG_ON(!rq_wq); |
| INIT_WORK(&rq_info.def_timer_work, def_work_fn); |
| spin_lock_init(&rq_lock); |
| rq_info.rq_poll_jiffies = DEFAULT_RQ_POLL_JIFFIES; |
| rq_info.def_timer_jiffies = DEFAULT_DEF_TIMER_JIFFIES; |
| rq_info.rq_poll_last_jiffy = 0; |
| rq_info.def_timer_last_jiffy = 0; |
| ret = init_rq_attribs(); |
| |
| rq_info.init = 1; |
| |
| for_each_possible_cpu(i) { |
| struct cpu_load_data *pcpu = &per_cpu(cpuload, i); |
| mutex_init(&pcpu->cpu_load_mutex); |
| cpufreq_get_policy(&cpu_policy, i); |
| pcpu->policy_max = cpu_policy.cpuinfo.max_freq; |
| cpumask_copy(pcpu->related_cpus, cpu_policy.cpus); |
| } |
| freq_transition.notifier_call = cpufreq_transition_handler; |
| cpu_hotplug.notifier_call = cpu_hotplug_handler; |
| cpufreq_register_notifier(&freq_transition, |
| CPUFREQ_TRANSITION_NOTIFIER); |
| register_hotcpu_notifier(&cpu_hotplug); |
| |
| return ret; |
| } |
| late_initcall(msm_rq_stats_init); |