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127 lines
2.2 KiB
127 lines
2.2 KiB
// SPDX-License-Identifier: GPL-2.0 |
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#include <linux/init.h> |
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#include <linux/kthread.h> |
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#include <linux/hrtimer.h> |
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#include <linux/fs.h> |
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#include <linux/debugfs.h> |
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#include <linux/export.h> |
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#include <linux/spinlock.h> |
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#include <asm/debug.h> |
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static int ss_get(void *data, u64 *val) |
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{ |
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ktime_t start, finish; |
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int loops; |
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int cont; |
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DEFINE_RAW_SPINLOCK(ss_spin); |
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loops = 1000000; |
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cont = 1; |
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start = ktime_get(); |
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while (cont) { |
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raw_spin_lock(&ss_spin); |
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loops--; |
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if (loops == 0) |
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cont = 0; |
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raw_spin_unlock(&ss_spin); |
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} |
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finish = ktime_get(); |
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*val = ktime_us_delta(finish, start); |
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return 0; |
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} |
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DEFINE_SIMPLE_ATTRIBUTE(fops_ss, ss_get, NULL, "%llu\n"); |
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struct spin_multi_state { |
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raw_spinlock_t lock; |
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atomic_t start_wait; |
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atomic_t enter_wait; |
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atomic_t exit_wait; |
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int loops; |
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}; |
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struct spin_multi_per_thread { |
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struct spin_multi_state *state; |
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ktime_t start; |
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}; |
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static int multi_other(void *data) |
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{ |
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int loops; |
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int cont; |
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struct spin_multi_per_thread *pt = data; |
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struct spin_multi_state *s = pt->state; |
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loops = s->loops; |
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cont = 1; |
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atomic_dec(&s->enter_wait); |
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while (atomic_read(&s->enter_wait)) |
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; /* spin */ |
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pt->start = ktime_get(); |
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atomic_dec(&s->start_wait); |
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while (atomic_read(&s->start_wait)) |
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; /* spin */ |
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while (cont) { |
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raw_spin_lock(&s->lock); |
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loops--; |
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if (loops == 0) |
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cont = 0; |
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raw_spin_unlock(&s->lock); |
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} |
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atomic_dec(&s->exit_wait); |
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while (atomic_read(&s->exit_wait)) |
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; /* spin */ |
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return 0; |
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} |
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static int multi_get(void *data, u64 *val) |
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{ |
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ktime_t finish; |
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struct spin_multi_state ms; |
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struct spin_multi_per_thread t1, t2; |
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ms.lock = __RAW_SPIN_LOCK_UNLOCKED("multi_get"); |
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ms.loops = 1000000; |
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atomic_set(&ms.start_wait, 2); |
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atomic_set(&ms.enter_wait, 2); |
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atomic_set(&ms.exit_wait, 2); |
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t1.state = &ms; |
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t2.state = &ms; |
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kthread_run(multi_other, &t2, "multi_get"); |
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multi_other(&t1); |
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finish = ktime_get(); |
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*val = ktime_us_delta(finish, t1.start); |
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return 0; |
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} |
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DEFINE_SIMPLE_ATTRIBUTE(fops_multi, multi_get, NULL, "%llu\n"); |
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static int __init spinlock_test(void) |
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{ |
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debugfs_create_file("spin_single", S_IRUGO, mips_debugfs_dir, NULL, |
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&fops_ss); |
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debugfs_create_file("spin_multi", S_IRUGO, mips_debugfs_dir, NULL, |
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&fops_multi); |
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return 0; |
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} |
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device_initcall(spinlock_test);
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