diff options
Diffstat (limited to 'drivers/cpufreq/dvfs_monitor.c')
| -rw-r--r-- | drivers/cpufreq/dvfs_monitor.c | 236 |
1 files changed, 0 insertions, 236 deletions
diff --git a/drivers/cpufreq/dvfs_monitor.c b/drivers/cpufreq/dvfs_monitor.c deleted file mode 100644 index e1e02b4..0000000 --- a/drivers/cpufreq/dvfs_monitor.c +++ /dev/null @@ -1,236 +0,0 @@ -#include <linux/kernel.h> -#include <linux/threads.h> -#include <linux/spinlock.h> -#include <linux/cpumask.h> -#include <linux/init.h> -#include <linux/cpufreq.h> -#include <linux/cpu.h> -#include <linux/notifier.h> -#include <linux/slab.h> -#include <linux/wait.h> -#include <linux/sched.h> -#include <linux/fs.h> -#include <linux/proc_fs.h> -#include <linux/atomic.h> -#include <linux/tick.h> - -struct cpufreq_load_data { - cputime64_t prev_idle; - cputime64_t prev_wall; - unsigned char load; -}; - -struct dvfs_data { - atomic_t opened; - atomic_t num_events; - unsigned char cpus[NR_CPUS]; - unsigned int prev_freq[NR_CPUS]; - unsigned int freq[NR_CPUS]; - struct cpufreq_load_data load_data[NR_CPUS]; - wait_queue_head_t wait_queue; - spinlock_t load_lock; -}; - -static struct dvfs_data *dvfs_info; - -static void init_dvfs_mon(void) -{ - int cpu; - int cur_freq = cpufreq_get(0); - - for_each_possible_cpu(cpu) { - dvfs_info->cpus[cpu] = cpu_online(cpu); - dvfs_info->freq[cpu] = cur_freq; - } - atomic_set(&dvfs_info->num_events, 1); -} - -static void calculate_load(void) -{ - int cpu; - cputime64_t cur_wall, cur_idle; - cputime64_t prev_wall, prev_idle; - unsigned int wall_time, idle_time; - unsigned long flags; - - spin_lock_irqsave(&dvfs_info->load_lock, flags); - for_each_online_cpu(cpu) { - cur_idle = get_cpu_idle_time_us(cpu, &cur_wall); - prev_idle = dvfs_info->load_data[cpu].prev_idle; - prev_wall = dvfs_info->load_data[cpu].prev_wall; - - dvfs_info->load_data[cpu].prev_idle = cur_idle; - dvfs_info->load_data[cpu].prev_wall = cur_wall; - - idle_time = (unsigned int)cputime64_sub(cur_idle, prev_idle); - wall_time = (unsigned int)cputime64_sub(cur_wall, prev_wall); - - if (wall_time < idle_time) { - pr_err("%s walltime < idletime\n", __func__); - dvfs_info->load_data[cpu].load = 0; - } - - dvfs_info->load_data[cpu].load = (wall_time - idle_time) * 100 - / wall_time; - } - spin_unlock_irqrestore(&dvfs_info->load_lock, flags); - return; -} - -static int dvfs_monitor_trans(struct notifier_block *nb, - unsigned long val, void *data) -{ - struct cpufreq_freqs *freq = data; - - if (val != CPUFREQ_POSTCHANGE) - return 0; - - if (freq->new == freq->old) - return 0; - - dvfs_info->prev_freq[freq->cpu] = freq->old; - dvfs_info->freq[freq->cpu] = freq->new; - - calculate_load(); - - atomic_inc(&dvfs_info->num_events); - wake_up_interruptible(&dvfs_info->wait_queue); - - return 0; -} - -static int __cpuinit dvfs_monitor_hotplug(struct notifier_block *nb, - unsigned long action, - void *hcpu) -{ - unsigned int cpu = (unsigned long)hcpu; - int cpu_status = 0; - - switch (action) { - case CPU_ONLINE: - cpu_status = 1; - break; - case CPU_DOWN_PREPARE: - cpu_status = 0; - break; - default: - return NOTIFY_OK; - } - - dvfs_info->cpus[cpu] = cpu_status; - atomic_inc(&dvfs_info->num_events); - calculate_load(); - wake_up_interruptible(&dvfs_info->wait_queue); - - return NOTIFY_OK; -} - -static struct notifier_block notifier_trans_block = { - .notifier_call = dvfs_monitor_trans, -}; - -static struct notifier_block notifier_hotplug_block __refdata = { - .notifier_call = dvfs_monitor_hotplug, - .priority = 1, -}; - -static int dvfs_mon_open(struct inode *inode, struct file *file) -{ - int ret = 0; - - if (atomic_xchg(&dvfs_info->opened, 1) != 0) - return -EBUSY; - - init_dvfs_mon(); - ret = cpufreq_register_notifier(¬ifier_trans_block, - CPUFREQ_TRANSITION_NOTIFIER); - if (ret) - return ret; - - register_hotcpu_notifier(¬ifier_hotplug_block); - - return 0; -} - -static int dvfs_mon_release(struct inode *inode, struct file *file) -{ - int ret = 0; - - atomic_dec(&dvfs_info->opened); - ret = cpufreq_unregister_notifier(¬ifier_trans_block, - CPUFREQ_TRANSITION_NOTIFIER); - unregister_hotcpu_notifier(¬ifier_hotplug_block); - - return ret; -} - -static ssize_t dvfs_mon_read(struct file *file, char __user *buf, - size_t count, loff_t *ppos) -{ - unsigned long long t; - unsigned long nanosec_rem; - int freq, prev_freq; - char cpu_status[NR_CPUS * 8 + 1]; - char temp[3]; - int i; - - wait_event_interruptible(dvfs_info->wait_queue, - atomic_read(&dvfs_info->num_events)); - - atomic_set(&dvfs_info->num_events, 0); - - /* for now, assume that all cores run on same speed */ - freq = dvfs_info->freq[0]; - prev_freq = dvfs_info->prev_freq[0]; - dvfs_info->prev_freq[0] = freq; - - memset(cpu_status, 0, sizeof(cpu_status)); - for (i = 0; i != num_possible_cpus(); ++i) { - unsigned char load = dvfs_info->cpus[i] ? - dvfs_info->load_data[i].load : 0; - sprintf(temp, "(%d,%3d),", dvfs_info->cpus[i], load); - strcat(cpu_status, temp); - } - - t = cpu_clock(0); - nanosec_rem = do_div(t, 1000000000); - - return sprintf(buf, "%lu.%06lu,%s%d,%d\n", - (unsigned long) t, nanosec_rem / 1000, - cpu_status, prev_freq, freq); -} - -static const struct file_operations dvfs_mon_operations = { - .read = dvfs_mon_read, - .open = dvfs_mon_open, - .release = dvfs_mon_release, -}; - -static int __init dvfs_monitor_init(void) -{ - dvfs_info = kzalloc(sizeof(struct dvfs_data), GFP_KERNEL); - if (dvfs_info == NULL) { - pr_err("[DVFS_MON] cannot allocate memory\n"); - return -ENOMEM; - } - - spin_lock_init(&dvfs_info->load_lock); - - init_waitqueue_head(&dvfs_info->wait_queue); - - proc_create("dvfs_mon", S_IRUSR, NULL, &dvfs_mon_operations); - - return 0; -} -late_initcall(dvfs_monitor_init); - -static void __exit dvfs_monitor_exit(void) -{ - kfree(dvfs_info); - return; -} -module_exit(dvfs_monitor_exit); - -MODULE_AUTHOR("ByungChang Cha <bc.cha@samsung.com>"); -MODULE_LICENSE("GPL"); -MODULE_DESCRIPTION("DVFS Monitoring proc file"); |