1#include <linux/init.h>
  2#include <linux/kthread.h>
  3#include <linux/hrtimer.h>
  4#include <linux/fs.h>
  5#include <linux/debugfs.h>
  6#include <linux/export.h>
  7#include <linux/spinlock.h>
  8#include <asm/debug.h>
  9
 10static int ss_get(void *data, u64 *val)
 11{
 12	ktime_t start, finish;
 13	int loops;
 14	int cont;
 15	DEFINE_RAW_SPINLOCK(ss_spin);
 16
 17	loops = 1000000;
 18	cont = 1;
 19
 20	start = ktime_get();
 21
 22	while (cont) {
 23		raw_spin_lock(&ss_spin);
 24		loops--;
 25		if (loops == 0)
 26			cont = 0;
 27		raw_spin_unlock(&ss_spin);
 28	}
 29
 30	finish = ktime_get();
 31
 32	*val = ktime_us_delta(finish, start);
 33
 34	return 0;
 35}
 36
 37DEFINE_SIMPLE_ATTRIBUTE(fops_ss, ss_get, NULL, "%llu\n");
 38
 39
 40
 41struct spin_multi_state {
 42	raw_spinlock_t lock;
 43	atomic_t start_wait;
 44	atomic_t enter_wait;
 45	atomic_t exit_wait;
 46	int loops;
 47};
 48
 49struct spin_multi_per_thread {
 50	struct spin_multi_state *state;
 51	ktime_t start;
 52};
 53
 54static int multi_other(void *data)
 55{
 56	int loops;
 57	int cont;
 58	struct spin_multi_per_thread *pt = data;
 59	struct spin_multi_state *s = pt->state;
 60
 61	loops = s->loops;
 62	cont = 1;
 63
 64	atomic_dec(&s->enter_wait);
 65
 66	while (atomic_read(&s->enter_wait))
 67		; /* spin */
 68
 69	pt->start = ktime_get();
 70
 71	atomic_dec(&s->start_wait);
 72
 73	while (atomic_read(&s->start_wait))
 74		; /* spin */
 75
 76	while (cont) {
 77		raw_spin_lock(&s->lock);
 78		loops--;
 79		if (loops == 0)
 80			cont = 0;
 81		raw_spin_unlock(&s->lock);
 82	}
 83
 84	atomic_dec(&s->exit_wait);
 85	while (atomic_read(&s->exit_wait))
 86		; /* spin */
 87	return 0;
 88}
 89
 90static int multi_get(void *data, u64 *val)
 91{
 92	ktime_t finish;
 93	struct spin_multi_state ms;
 94	struct spin_multi_per_thread t1, t2;
 95
 96	ms.lock = __RAW_SPIN_LOCK_UNLOCKED("multi_get");
 97	ms.loops = 1000000;
 98
 99	atomic_set(&ms.start_wait, 2);
100	atomic_set(&ms.enter_wait, 2);
101	atomic_set(&ms.exit_wait, 2);
102	t1.state = &ms;
103	t2.state = &ms;
104
105	kthread_run(multi_other, &t2, "multi_get");
106
107	multi_other(&t1);
108
109	finish = ktime_get();
110
111	*val = ktime_us_delta(finish, t1.start);
112
113	return 0;
114}
115
116DEFINE_SIMPLE_ATTRIBUTE(fops_multi, multi_get, NULL, "%llu\n");
117
 
 
118static int __init spinlock_test(void)
119{
120	struct dentry *d;
121
122	if (!mips_debugfs_dir)
123		return -ENODEV;
124
125	d = debugfs_create_file("spin_single", S_IRUGO,
126				mips_debugfs_dir, NULL,
127				&fops_ss);
128	if (!d)
129		return -ENOMEM;
130
131	d = debugfs_create_file("spin_multi", S_IRUGO,
132				mips_debugfs_dir, NULL,
133				&fops_multi);
134	if (!d)
135		return -ENOMEM;
136
137	return 0;
138}
139device_initcall(spinlock_test);

  1#include <linux/init.h>
  2#include <linux/kthread.h>
  3#include <linux/hrtimer.h>
  4#include <linux/fs.h>
  5#include <linux/debugfs.h>
  6#include <linux/module.h>
  7#include <linux/spinlock.h>
  8
  9
 10static int ss_get(void *data, u64 *val)
 11{
 12	ktime_t start, finish;
 13	int loops;
 14	int cont;
 15	DEFINE_RAW_SPINLOCK(ss_spin);
 16
 17	loops = 1000000;
 18	cont = 1;
 19
 20	start = ktime_get();
 21
 22	while (cont) {
 23		raw_spin_lock(&ss_spin);
 24		loops--;
 25		if (loops == 0)
 26			cont = 0;
 27		raw_spin_unlock(&ss_spin);
 28	}
 29
 30	finish = ktime_get();
 31
 32	*val = ktime_us_delta(finish, start);
 33
 34	return 0;
 35}
 36
 37DEFINE_SIMPLE_ATTRIBUTE(fops_ss, ss_get, NULL, "%llu\n");
 38
 39
 40
 41struct spin_multi_state {
 42	raw_spinlock_t lock;
 43	atomic_t start_wait;
 44	atomic_t enter_wait;
 45	atomic_t exit_wait;
 46	int loops;
 47};
 48
 49struct spin_multi_per_thread {
 50	struct spin_multi_state *state;
 51	ktime_t start;
 52};
 53
 54static int multi_other(void *data)
 55{
 56	int loops;
 57	int cont;
 58	struct spin_multi_per_thread *pt = data;
 59	struct spin_multi_state *s = pt->state;
 60
 61	loops = s->loops;
 62	cont = 1;
 63
 64	atomic_dec(&s->enter_wait);
 65
 66	while (atomic_read(&s->enter_wait))
 67		; /* spin */
 68
 69	pt->start = ktime_get();
 70
 71	atomic_dec(&s->start_wait);
 72
 73	while (atomic_read(&s->start_wait))
 74		; /* spin */
 75
 76	while (cont) {
 77		raw_spin_lock(&s->lock);
 78		loops--;
 79		if (loops == 0)
 80			cont = 0;
 81		raw_spin_unlock(&s->lock);
 82	}
 83
 84	atomic_dec(&s->exit_wait);
 85	while (atomic_read(&s->exit_wait))
 86		; /* spin */
 87	return 0;
 88}
 89
 90static int multi_get(void *data, u64 *val)
 91{
 92	ktime_t finish;
 93	struct spin_multi_state ms;
 94	struct spin_multi_per_thread t1, t2;
 95
 96	ms.lock = __RAW_SPIN_LOCK_UNLOCKED("multi_get");
 97	ms.loops = 1000000;
 98
 99	atomic_set(&ms.start_wait, 2);
100	atomic_set(&ms.enter_wait, 2);
101	atomic_set(&ms.exit_wait, 2);
102	t1.state = &ms;
103	t2.state = &ms;
104
105	kthread_run(multi_other, &t2, "multi_get");
106
107	multi_other(&t1);
108
109	finish = ktime_get();
110
111	*val = ktime_us_delta(finish, t1.start);
112
113	return 0;
114}
115
116DEFINE_SIMPLE_ATTRIBUTE(fops_multi, multi_get, NULL, "%llu\n");
117
118
119extern struct dentry *mips_debugfs_dir;
120static int __init spinlock_test(void)
121{
122	struct dentry *d;
123
124	if (!mips_debugfs_dir)
125		return -ENODEV;
126
127	d = debugfs_create_file("spin_single", S_IRUGO,
128				mips_debugfs_dir, NULL,
129				&fops_ss);
130	if (!d)
131		return -ENOMEM;
132
133	d = debugfs_create_file("spin_multi", S_IRUGO,
134				mips_debugfs_dir, NULL,
135				&fops_multi);
136	if (!d)
137		return -ENOMEM;
138
139	return 0;
140}
141device_initcall(spinlock_test);