[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / activity_stats.c

/* net/activity_stats.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/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/suspend.h>
#include <net/net_namespace.h>

/*
 * Track transmission rates in buckets (power of 2).
 * 1,2,4,8...512 seconds.
 *
 * Buckets represent the count of network transmissions at least
 * N seconds apart, where N is 1 << bucket index.
 */
#define BUCKET_MAX 10

/* Track network activity frequency */
static unsigned long activity_stats[BUCKET_MAX];
static ktime_t last_transmit;
static ktime_t suspend_time;
static DEFINE_SPINLOCK(activity_lock);

void activity_stats_update(void)
{
	int i;
	unsigned long flags;
	ktime_t now;
	s64 delta;

	spin_lock_irqsave(&activity_lock, flags);
	now = ktime_get();
	delta = ktime_to_ns(ktime_sub(now, last_transmit));

	for (i = BUCKET_MAX - 1; i >= 0; i--) {
		/*
		 * Check if the time delta between network activity is within the
		 * minimum bucket range.
		 */
		if (delta < (1000000000ULL << i))
			continue;

		activity_stats[i]++;
		last_transmit = now;
		break;
	}
	spin_unlock_irqrestore(&activity_lock, flags);
}

static int activity_stats_show(struct seq_file *m, void *v)
{
	int i;
	int ret;

	seq_printf(m, "Min Bucket(sec) Count\n");

	for (i = 0; i < BUCKET_MAX; i++) {
		ret = seq_printf(m, "%15d %lu\n", 1 << i, activity_stats[i]);
		if (ret)
			return ret;
	}

	return 0;
}

static int activity_stats_notifier(struct notifier_block *nb,
					unsigned long event, void *dummy)
{
	switch (event) {
		case PM_SUSPEND_PREPARE:
			suspend_time = ktime_get_real();
			break;

		case PM_POST_SUSPEND:
			suspend_time = ktime_sub(ktime_get_real(), suspend_time);
			last_transmit = ktime_sub(last_transmit, suspend_time);
	}

	return 0;
}

static int activity_stats_open(struct inode *inode, struct file *file)
{
	return single_open(file, activity_stats_show, PDE_DATA(inode));
}

static const struct file_operations activity_stats_fops = {
	.open		= activity_stats_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};

static struct notifier_block activity_stats_notifier_block = {
	.notifier_call = activity_stats_notifier,
};

static int  __init activity_stats_init(void)
{
	proc_create("activity", S_IRUGO,
		    init_net.proc_net_stat, &activity_stats_fops);
	return register_pm_notifier(&activity_stats_notifier_block);
}

subsys_initcall(activity_stats_init);
Commit	Line	Data
6fa3eb70 S	1	/* net/activity_stats.c
	2	*
	3	* Copyright (C) 2010 Google, Inc.
	4	*
	5	* This software is licensed under the terms of the GNU General Public
	6	* License version 2, as published by the Free Software Foundation, and
	7	* may be copied, distributed, and modified under those terms.
	8	*
	9	* This program is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
	13	*
	14	* Author: Mike Chan (mike@android.com)
	15	*/
	16
	17	#include <linux/proc_fs.h>
	18	#include <linux/seq_file.h>
	19	#include <linux/suspend.h>
	20	#include <net/net_namespace.h>
	21
	22	/*
	23	* Track transmission rates in buckets (power of 2).
	24	* 1,2,4,8...512 seconds.
	25	*
	26	* Buckets represent the count of network transmissions at least
	27	* N seconds apart, where N is 1 << bucket index.
	28	*/
	29	#define BUCKET_MAX 10
	30
	31	/* Track network activity frequency */
	32	static unsigned long activity_stats[BUCKET_MAX];
	33	static ktime_t last_transmit;
	34	static ktime_t suspend_time;
	35	static DEFINE_SPINLOCK(activity_lock);
	36
	37	void activity_stats_update(void)
	38	{
	39	int i;
	40	unsigned long flags;
	41	ktime_t now;
	42	s64 delta;
	43
	44	spin_lock_irqsave(&activity_lock, flags);
	45	now = ktime_get();
	46	delta = ktime_to_ns(ktime_sub(now, last_transmit));
	47
	48	for (i = BUCKET_MAX - 1; i >= 0; i--) {
	49	/*
	50	* Check if the time delta between network activity is within the
	51	* minimum bucket range.
	52	*/
	53	if (delta < (1000000000ULL << i))
	54	continue;
	55
	56	activity_stats[i]++;
	57	last_transmit = now;
	58	break;
	59	}
	60	spin_unlock_irqrestore(&activity_lock, flags);
	61	}
	62
	63	static int activity_stats_show(struct seq_file m, void v)
	64	{
65	int i;
66	int ret;
67
68	seq_printf(m, "Min Bucket(sec) Count\n");
69
70	for (i = 0; i < BUCKET_MAX; i++) {
71	ret = seq_printf(m, "%15d %lu\n", 1 << i, activity_stats[i]);
72	if (ret)
73	return ret;
74	}
75
76	return 0;
77	}
78
79	static int activity_stats_notifier(struct notifier_block *nb,
80	unsigned long event, void *dummy)
81	{
82	switch (event) {
83	case PM_SUSPEND_PREPARE:
84	suspend_time = ktime_get_real();
85	break;
86
87	case PM_POST_SUSPEND:
88	suspend_time = ktime_sub(ktime_get_real(), suspend_time);
89	last_transmit = ktime_sub(last_transmit, suspend_time);
90	}
91
92	return 0;
93	}
94
95	static int activity_stats_open(struct inode inode, struct file file)
96	{
97	return single_open(file, activity_stats_show, PDE_DATA(inode));
98	}
99
100	static const struct file_operations activity_stats_fops = {
101	.open = activity_stats_open,
102	.read = seq_read,
103	.llseek = seq_lseek,
104	.release = seq_release,
105	};
106
107	static struct notifier_block activity_stats_notifier_block = {
108	.notifier_call = activity_stats_notifier,
109	};
110
111	static int __init activity_stats_init(void)
112	{
113	proc_create("activity", S_IRUGO,
114	init_net.proc_net_stat, &activity_stats_fops);
115	return register_pm_notifier(&activity_stats_notifier_block);
116	}
117
118	subsys_initcall(activity_stats_init);
119