142 строки
2.3 KiB
C
142 строки
2.3 KiB
C
#include <linux/init.h>
|
|
#include <linux/kthread.h>
|
|
#include <linux/hrtimer.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/debugfs.h>
|
|
#include <linux/module.h>
|
|
#include <linux/spinlock.h>
|
|
|
|
|
|
static int ss_get(void *data, u64 *val)
|
|
{
|
|
ktime_t start, finish;
|
|
int loops;
|
|
int cont;
|
|
DEFINE_RAW_SPINLOCK(ss_spin);
|
|
|
|
loops = 1000000;
|
|
cont = 1;
|
|
|
|
start = ktime_get();
|
|
|
|
while (cont) {
|
|
raw_spin_lock(&ss_spin);
|
|
loops--;
|
|
if (loops == 0)
|
|
cont = 0;
|
|
raw_spin_unlock(&ss_spin);
|
|
}
|
|
|
|
finish = ktime_get();
|
|
|
|
*val = ktime_us_delta(finish, start);
|
|
|
|
return 0;
|
|
}
|
|
|
|
DEFINE_SIMPLE_ATTRIBUTE(fops_ss, ss_get, NULL, "%llu\n");
|
|
|
|
|
|
|
|
struct spin_multi_state {
|
|
raw_spinlock_t lock;
|
|
atomic_t start_wait;
|
|
atomic_t enter_wait;
|
|
atomic_t exit_wait;
|
|
int loops;
|
|
};
|
|
|
|
struct spin_multi_per_thread {
|
|
struct spin_multi_state *state;
|
|
ktime_t start;
|
|
};
|
|
|
|
static int multi_other(void *data)
|
|
{
|
|
int loops;
|
|
int cont;
|
|
struct spin_multi_per_thread *pt = data;
|
|
struct spin_multi_state *s = pt->state;
|
|
|
|
loops = s->loops;
|
|
cont = 1;
|
|
|
|
atomic_dec(&s->enter_wait);
|
|
|
|
while (atomic_read(&s->enter_wait))
|
|
; /* spin */
|
|
|
|
pt->start = ktime_get();
|
|
|
|
atomic_dec(&s->start_wait);
|
|
|
|
while (atomic_read(&s->start_wait))
|
|
; /* spin */
|
|
|
|
while (cont) {
|
|
raw_spin_lock(&s->lock);
|
|
loops--;
|
|
if (loops == 0)
|
|
cont = 0;
|
|
raw_spin_unlock(&s->lock);
|
|
}
|
|
|
|
atomic_dec(&s->exit_wait);
|
|
while (atomic_read(&s->exit_wait))
|
|
; /* spin */
|
|
return 0;
|
|
}
|
|
|
|
static int multi_get(void *data, u64 *val)
|
|
{
|
|
ktime_t finish;
|
|
struct spin_multi_state ms;
|
|
struct spin_multi_per_thread t1, t2;
|
|
|
|
ms.lock = __RAW_SPIN_LOCK_UNLOCKED("multi_get");
|
|
ms.loops = 1000000;
|
|
|
|
atomic_set(&ms.start_wait, 2);
|
|
atomic_set(&ms.enter_wait, 2);
|
|
atomic_set(&ms.exit_wait, 2);
|
|
t1.state = &ms;
|
|
t2.state = &ms;
|
|
|
|
kthread_run(multi_other, &t2, "multi_get");
|
|
|
|
multi_other(&t1);
|
|
|
|
finish = ktime_get();
|
|
|
|
*val = ktime_us_delta(finish, t1.start);
|
|
|
|
return 0;
|
|
}
|
|
|
|
DEFINE_SIMPLE_ATTRIBUTE(fops_multi, multi_get, NULL, "%llu\n");
|
|
|
|
|
|
extern struct dentry *mips_debugfs_dir;
|
|
static int __init spinlock_test(void)
|
|
{
|
|
struct dentry *d;
|
|
|
|
if (!mips_debugfs_dir)
|
|
return -ENODEV;
|
|
|
|
d = debugfs_create_file("spin_single", S_IRUGO,
|
|
mips_debugfs_dir, NULL,
|
|
&fops_ss);
|
|
if (!d)
|
|
return -ENOMEM;
|
|
|
|
d = debugfs_create_file("spin_multi", S_IRUGO,
|
|
mips_debugfs_dir, NULL,
|
|
&fops_multi);
|
|
if (!d)
|
|
return -ENOMEM;
|
|
|
|
return 0;
|
|
}
|
|
device_initcall(spinlock_test);
|