mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
615 lines
16 KiB
615 lines
16 KiB
// SPDX-License-Identifier: GPL-2.0 |
|
/* |
|
* Test module to generate lockups |
|
*/ |
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
|
|
|
#include <linux/kernel.h> |
|
#include <linux/module.h> |
|
#include <linux/delay.h> |
|
#include <linux/sched.h> |
|
#include <linux/sched/signal.h> |
|
#include <linux/sched/clock.h> |
|
#include <linux/cpu.h> |
|
#include <linux/nmi.h> |
|
#include <linux/mm.h> |
|
#include <linux/uaccess.h> |
|
#include <linux/file.h> |
|
|
|
static unsigned int time_secs; |
|
module_param(time_secs, uint, 0600); |
|
MODULE_PARM_DESC(time_secs, "lockup time in seconds, default 0"); |
|
|
|
static unsigned int time_nsecs; |
|
module_param(time_nsecs, uint, 0600); |
|
MODULE_PARM_DESC(time_nsecs, "nanoseconds part of lockup time, default 0"); |
|
|
|
static unsigned int cooldown_secs; |
|
module_param(cooldown_secs, uint, 0600); |
|
MODULE_PARM_DESC(cooldown_secs, "cooldown time between iterations in seconds, default 0"); |
|
|
|
static unsigned int cooldown_nsecs; |
|
module_param(cooldown_nsecs, uint, 0600); |
|
MODULE_PARM_DESC(cooldown_nsecs, "nanoseconds part of cooldown, default 0"); |
|
|
|
static unsigned int iterations = 1; |
|
module_param(iterations, uint, 0600); |
|
MODULE_PARM_DESC(iterations, "lockup iterations, default 1"); |
|
|
|
static bool all_cpus; |
|
module_param(all_cpus, bool, 0400); |
|
MODULE_PARM_DESC(all_cpus, "trigger lockup at all cpus at once"); |
|
|
|
static int wait_state; |
|
static char *state = "R"; |
|
module_param(state, charp, 0400); |
|
MODULE_PARM_DESC(state, "wait in 'R' running (default), 'D' uninterruptible, 'K' killable, 'S' interruptible state"); |
|
|
|
static bool use_hrtimer; |
|
module_param(use_hrtimer, bool, 0400); |
|
MODULE_PARM_DESC(use_hrtimer, "use high-resolution timer for sleeping"); |
|
|
|
static bool iowait; |
|
module_param(iowait, bool, 0400); |
|
MODULE_PARM_DESC(iowait, "account sleep time as iowait"); |
|
|
|
static bool lock_read; |
|
module_param(lock_read, bool, 0400); |
|
MODULE_PARM_DESC(lock_read, "lock read-write locks for read"); |
|
|
|
static bool lock_single; |
|
module_param(lock_single, bool, 0400); |
|
MODULE_PARM_DESC(lock_single, "acquire locks only at one cpu"); |
|
|
|
static bool reacquire_locks; |
|
module_param(reacquire_locks, bool, 0400); |
|
MODULE_PARM_DESC(reacquire_locks, "release and reacquire locks/irq/preempt between iterations"); |
|
|
|
static bool touch_softlockup; |
|
module_param(touch_softlockup, bool, 0600); |
|
MODULE_PARM_DESC(touch_softlockup, "touch soft-lockup watchdog between iterations"); |
|
|
|
static bool touch_hardlockup; |
|
module_param(touch_hardlockup, bool, 0600); |
|
MODULE_PARM_DESC(touch_hardlockup, "touch hard-lockup watchdog between iterations"); |
|
|
|
static bool call_cond_resched; |
|
module_param(call_cond_resched, bool, 0600); |
|
MODULE_PARM_DESC(call_cond_resched, "call cond_resched() between iterations"); |
|
|
|
static bool measure_lock_wait; |
|
module_param(measure_lock_wait, bool, 0400); |
|
MODULE_PARM_DESC(measure_lock_wait, "measure lock wait time"); |
|
|
|
static unsigned long lock_wait_threshold = ULONG_MAX; |
|
module_param(lock_wait_threshold, ulong, 0400); |
|
MODULE_PARM_DESC(lock_wait_threshold, "print lock wait time longer than this in nanoseconds, default off"); |
|
|
|
static bool test_disable_irq; |
|
module_param_named(disable_irq, test_disable_irq, bool, 0400); |
|
MODULE_PARM_DESC(disable_irq, "disable interrupts: generate hard-lockups"); |
|
|
|
static bool disable_softirq; |
|
module_param(disable_softirq, bool, 0400); |
|
MODULE_PARM_DESC(disable_softirq, "disable bottom-half irq handlers"); |
|
|
|
static bool disable_preempt; |
|
module_param(disable_preempt, bool, 0400); |
|
MODULE_PARM_DESC(disable_preempt, "disable preemption: generate soft-lockups"); |
|
|
|
static bool lock_rcu; |
|
module_param(lock_rcu, bool, 0400); |
|
MODULE_PARM_DESC(lock_rcu, "grab rcu_read_lock: generate rcu stalls"); |
|
|
|
static bool lock_mmap_sem; |
|
module_param(lock_mmap_sem, bool, 0400); |
|
MODULE_PARM_DESC(lock_mmap_sem, "lock mm->mmap_lock: block procfs interfaces"); |
|
|
|
static unsigned long lock_rwsem_ptr; |
|
module_param_unsafe(lock_rwsem_ptr, ulong, 0400); |
|
MODULE_PARM_DESC(lock_rwsem_ptr, "lock rw_semaphore at address"); |
|
|
|
static unsigned long lock_mutex_ptr; |
|
module_param_unsafe(lock_mutex_ptr, ulong, 0400); |
|
MODULE_PARM_DESC(lock_mutex_ptr, "lock mutex at address"); |
|
|
|
static unsigned long lock_spinlock_ptr; |
|
module_param_unsafe(lock_spinlock_ptr, ulong, 0400); |
|
MODULE_PARM_DESC(lock_spinlock_ptr, "lock spinlock at address"); |
|
|
|
static unsigned long lock_rwlock_ptr; |
|
module_param_unsafe(lock_rwlock_ptr, ulong, 0400); |
|
MODULE_PARM_DESC(lock_rwlock_ptr, "lock rwlock at address"); |
|
|
|
static unsigned int alloc_pages_nr; |
|
module_param_unsafe(alloc_pages_nr, uint, 0600); |
|
MODULE_PARM_DESC(alloc_pages_nr, "allocate and free pages under locks"); |
|
|
|
static unsigned int alloc_pages_order; |
|
module_param(alloc_pages_order, uint, 0400); |
|
MODULE_PARM_DESC(alloc_pages_order, "page order to allocate"); |
|
|
|
static gfp_t alloc_pages_gfp = GFP_KERNEL; |
|
module_param_unsafe(alloc_pages_gfp, uint, 0400); |
|
MODULE_PARM_DESC(alloc_pages_gfp, "allocate pages with this gfp_mask, default GFP_KERNEL"); |
|
|
|
static bool alloc_pages_atomic; |
|
module_param(alloc_pages_atomic, bool, 0400); |
|
MODULE_PARM_DESC(alloc_pages_atomic, "allocate pages with GFP_ATOMIC"); |
|
|
|
static bool reallocate_pages; |
|
module_param(reallocate_pages, bool, 0400); |
|
MODULE_PARM_DESC(reallocate_pages, "free and allocate pages between iterations"); |
|
|
|
struct file *test_file; |
|
static struct inode *test_inode; |
|
static char test_file_path[256]; |
|
module_param_string(file_path, test_file_path, sizeof(test_file_path), 0400); |
|
MODULE_PARM_DESC(file_path, "file path to test"); |
|
|
|
static bool test_lock_inode; |
|
module_param_named(lock_inode, test_lock_inode, bool, 0400); |
|
MODULE_PARM_DESC(lock_inode, "lock file -> inode -> i_rwsem"); |
|
|
|
static bool test_lock_mapping; |
|
module_param_named(lock_mapping, test_lock_mapping, bool, 0400); |
|
MODULE_PARM_DESC(lock_mapping, "lock file -> mapping -> i_mmap_rwsem"); |
|
|
|
static bool test_lock_sb_umount; |
|
module_param_named(lock_sb_umount, test_lock_sb_umount, bool, 0400); |
|
MODULE_PARM_DESC(lock_sb_umount, "lock file -> sb -> s_umount"); |
|
|
|
static atomic_t alloc_pages_failed = ATOMIC_INIT(0); |
|
|
|
static atomic64_t max_lock_wait = ATOMIC64_INIT(0); |
|
|
|
static struct task_struct *main_task; |
|
static int master_cpu; |
|
|
|
static void test_lock(bool master, bool verbose) |
|
{ |
|
u64 wait_start; |
|
|
|
if (measure_lock_wait) |
|
wait_start = local_clock(); |
|
|
|
if (lock_mutex_ptr && master) { |
|
if (verbose) |
|
pr_notice("lock mutex %ps\n", (void *)lock_mutex_ptr); |
|
mutex_lock((struct mutex *)lock_mutex_ptr); |
|
} |
|
|
|
if (lock_rwsem_ptr && master) { |
|
if (verbose) |
|
pr_notice("lock rw_semaphore %ps\n", |
|
(void *)lock_rwsem_ptr); |
|
if (lock_read) |
|
down_read((struct rw_semaphore *)lock_rwsem_ptr); |
|
else |
|
down_write((struct rw_semaphore *)lock_rwsem_ptr); |
|
} |
|
|
|
if (lock_mmap_sem && master) { |
|
if (verbose) |
|
pr_notice("lock mmap_lock pid=%d\n", main_task->pid); |
|
if (lock_read) |
|
mmap_read_lock(main_task->mm); |
|
else |
|
mmap_write_lock(main_task->mm); |
|
} |
|
|
|
if (test_disable_irq) |
|
local_irq_disable(); |
|
|
|
if (disable_softirq) |
|
local_bh_disable(); |
|
|
|
if (disable_preempt) |
|
preempt_disable(); |
|
|
|
if (lock_rcu) |
|
rcu_read_lock(); |
|
|
|
if (lock_spinlock_ptr && master) { |
|
if (verbose) |
|
pr_notice("lock spinlock %ps\n", |
|
(void *)lock_spinlock_ptr); |
|
spin_lock((spinlock_t *)lock_spinlock_ptr); |
|
} |
|
|
|
if (lock_rwlock_ptr && master) { |
|
if (verbose) |
|
pr_notice("lock rwlock %ps\n", |
|
(void *)lock_rwlock_ptr); |
|
if (lock_read) |
|
read_lock((rwlock_t *)lock_rwlock_ptr); |
|
else |
|
write_lock((rwlock_t *)lock_rwlock_ptr); |
|
} |
|
|
|
if (measure_lock_wait) { |
|
s64 cur_wait = local_clock() - wait_start; |
|
s64 max_wait = atomic64_read(&max_lock_wait); |
|
|
|
do { |
|
if (cur_wait < max_wait) |
|
break; |
|
max_wait = atomic64_cmpxchg(&max_lock_wait, |
|
max_wait, cur_wait); |
|
} while (max_wait != cur_wait); |
|
|
|
if (cur_wait > lock_wait_threshold) |
|
pr_notice_ratelimited("lock wait %lld ns\n", cur_wait); |
|
} |
|
} |
|
|
|
static void test_unlock(bool master, bool verbose) |
|
{ |
|
if (lock_rwlock_ptr && master) { |
|
if (lock_read) |
|
read_unlock((rwlock_t *)lock_rwlock_ptr); |
|
else |
|
write_unlock((rwlock_t *)lock_rwlock_ptr); |
|
if (verbose) |
|
pr_notice("unlock rwlock %ps\n", |
|
(void *)lock_rwlock_ptr); |
|
} |
|
|
|
if (lock_spinlock_ptr && master) { |
|
spin_unlock((spinlock_t *)lock_spinlock_ptr); |
|
if (verbose) |
|
pr_notice("unlock spinlock %ps\n", |
|
(void *)lock_spinlock_ptr); |
|
} |
|
|
|
if (lock_rcu) |
|
rcu_read_unlock(); |
|
|
|
if (disable_preempt) |
|
preempt_enable(); |
|
|
|
if (disable_softirq) |
|
local_bh_enable(); |
|
|
|
if (test_disable_irq) |
|
local_irq_enable(); |
|
|
|
if (lock_mmap_sem && master) { |
|
if (lock_read) |
|
mmap_read_unlock(main_task->mm); |
|
else |
|
mmap_write_unlock(main_task->mm); |
|
if (verbose) |
|
pr_notice("unlock mmap_lock pid=%d\n", main_task->pid); |
|
} |
|
|
|
if (lock_rwsem_ptr && master) { |
|
if (lock_read) |
|
up_read((struct rw_semaphore *)lock_rwsem_ptr); |
|
else |
|
up_write((struct rw_semaphore *)lock_rwsem_ptr); |
|
if (verbose) |
|
pr_notice("unlock rw_semaphore %ps\n", |
|
(void *)lock_rwsem_ptr); |
|
} |
|
|
|
if (lock_mutex_ptr && master) { |
|
mutex_unlock((struct mutex *)lock_mutex_ptr); |
|
if (verbose) |
|
pr_notice("unlock mutex %ps\n", |
|
(void *)lock_mutex_ptr); |
|
} |
|
} |
|
|
|
static void test_alloc_pages(struct list_head *pages) |
|
{ |
|
struct page *page; |
|
unsigned int i; |
|
|
|
for (i = 0; i < alloc_pages_nr; i++) { |
|
page = alloc_pages(alloc_pages_gfp, alloc_pages_order); |
|
if (!page) { |
|
atomic_inc(&alloc_pages_failed); |
|
break; |
|
} |
|
list_add(&page->lru, pages); |
|
} |
|
} |
|
|
|
static void test_free_pages(struct list_head *pages) |
|
{ |
|
struct page *page, *next; |
|
|
|
list_for_each_entry_safe(page, next, pages, lru) |
|
__free_pages(page, alloc_pages_order); |
|
INIT_LIST_HEAD(pages); |
|
} |
|
|
|
static void test_wait(unsigned int secs, unsigned int nsecs) |
|
{ |
|
if (wait_state == TASK_RUNNING) { |
|
if (secs) |
|
mdelay(secs * MSEC_PER_SEC); |
|
if (nsecs) |
|
ndelay(nsecs); |
|
return; |
|
} |
|
|
|
__set_current_state(wait_state); |
|
if (use_hrtimer) { |
|
ktime_t time; |
|
|
|
time = ns_to_ktime((u64)secs * NSEC_PER_SEC + nsecs); |
|
schedule_hrtimeout(&time, HRTIMER_MODE_REL); |
|
} else { |
|
schedule_timeout(secs * HZ + nsecs_to_jiffies(nsecs)); |
|
} |
|
} |
|
|
|
static void test_lockup(bool master) |
|
{ |
|
u64 lockup_start = local_clock(); |
|
unsigned int iter = 0; |
|
LIST_HEAD(pages); |
|
|
|
pr_notice("Start on CPU%d\n", raw_smp_processor_id()); |
|
|
|
test_lock(master, true); |
|
|
|
test_alloc_pages(&pages); |
|
|
|
while (iter++ < iterations && !signal_pending(main_task)) { |
|
|
|
if (iowait) |
|
current->in_iowait = 1; |
|
|
|
test_wait(time_secs, time_nsecs); |
|
|
|
if (iowait) |
|
current->in_iowait = 0; |
|
|
|
if (reallocate_pages) |
|
test_free_pages(&pages); |
|
|
|
if (reacquire_locks) |
|
test_unlock(master, false); |
|
|
|
if (touch_softlockup) |
|
touch_softlockup_watchdog(); |
|
|
|
if (touch_hardlockup) |
|
touch_nmi_watchdog(); |
|
|
|
if (call_cond_resched) |
|
cond_resched(); |
|
|
|
test_wait(cooldown_secs, cooldown_nsecs); |
|
|
|
if (reacquire_locks) |
|
test_lock(master, false); |
|
|
|
if (reallocate_pages) |
|
test_alloc_pages(&pages); |
|
} |
|
|
|
pr_notice("Finish on CPU%d in %lld ns\n", raw_smp_processor_id(), |
|
local_clock() - lockup_start); |
|
|
|
test_free_pages(&pages); |
|
|
|
test_unlock(master, true); |
|
} |
|
|
|
static DEFINE_PER_CPU(struct work_struct, test_works); |
|
|
|
static void test_work_fn(struct work_struct *work) |
|
{ |
|
test_lockup(!lock_single || |
|
work == per_cpu_ptr(&test_works, master_cpu)); |
|
} |
|
|
|
static bool test_kernel_ptr(unsigned long addr, int size) |
|
{ |
|
void *ptr = (void *)addr; |
|
char buf; |
|
|
|
if (!addr) |
|
return false; |
|
|
|
/* should be at least readable kernel address */ |
|
if (access_ok(ptr, 1) || |
|
access_ok(ptr + size - 1, 1) || |
|
get_kernel_nofault(buf, ptr) || |
|
get_kernel_nofault(buf, ptr + size - 1)) { |
|
pr_err("invalid kernel ptr: %#lx\n", addr); |
|
return true; |
|
} |
|
|
|
return false; |
|
} |
|
|
|
static bool __maybe_unused test_magic(unsigned long addr, int offset, |
|
unsigned int expected) |
|
{ |
|
void *ptr = (void *)addr + offset; |
|
unsigned int magic = 0; |
|
|
|
if (!addr) |
|
return false; |
|
|
|
if (get_kernel_nofault(magic, ptr) || magic != expected) { |
|
pr_err("invalid magic at %#lx + %#x = %#x, expected %#x\n", |
|
addr, offset, magic, expected); |
|
return true; |
|
} |
|
|
|
return false; |
|
} |
|
|
|
static int __init test_lockup_init(void) |
|
{ |
|
u64 test_start = local_clock(); |
|
|
|
main_task = current; |
|
|
|
switch (state[0]) { |
|
case 'S': |
|
wait_state = TASK_INTERRUPTIBLE; |
|
break; |
|
case 'D': |
|
wait_state = TASK_UNINTERRUPTIBLE; |
|
break; |
|
case 'K': |
|
wait_state = TASK_KILLABLE; |
|
break; |
|
case 'R': |
|
wait_state = TASK_RUNNING; |
|
break; |
|
default: |
|
pr_err("unknown state=%s\n", state); |
|
return -EINVAL; |
|
} |
|
|
|
if (alloc_pages_atomic) |
|
alloc_pages_gfp = GFP_ATOMIC; |
|
|
|
if (test_kernel_ptr(lock_spinlock_ptr, sizeof(spinlock_t)) || |
|
test_kernel_ptr(lock_rwlock_ptr, sizeof(rwlock_t)) || |
|
test_kernel_ptr(lock_mutex_ptr, sizeof(struct mutex)) || |
|
test_kernel_ptr(lock_rwsem_ptr, sizeof(struct rw_semaphore))) |
|
return -EINVAL; |
|
|
|
#ifdef CONFIG_DEBUG_SPINLOCK |
|
#ifdef CONFIG_PREEMPT_RT |
|
if (test_magic(lock_spinlock_ptr, |
|
offsetof(spinlock_t, lock.wait_lock.magic), |
|
SPINLOCK_MAGIC) || |
|
test_magic(lock_rwlock_ptr, |
|
offsetof(rwlock_t, rtmutex.wait_lock.magic), |
|
SPINLOCK_MAGIC) || |
|
test_magic(lock_mutex_ptr, |
|
offsetof(struct mutex, lock.wait_lock.magic), |
|
SPINLOCK_MAGIC) || |
|
test_magic(lock_rwsem_ptr, |
|
offsetof(struct rw_semaphore, rtmutex.wait_lock.magic), |
|
SPINLOCK_MAGIC)) |
|
return -EINVAL; |
|
#else |
|
if (test_magic(lock_spinlock_ptr, |
|
offsetof(spinlock_t, rlock.magic), |
|
SPINLOCK_MAGIC) || |
|
test_magic(lock_rwlock_ptr, |
|
offsetof(rwlock_t, magic), |
|
RWLOCK_MAGIC) || |
|
test_magic(lock_mutex_ptr, |
|
offsetof(struct mutex, wait_lock.rlock.magic), |
|
SPINLOCK_MAGIC) || |
|
test_magic(lock_rwsem_ptr, |
|
offsetof(struct rw_semaphore, wait_lock.magic), |
|
SPINLOCK_MAGIC)) |
|
return -EINVAL; |
|
#endif |
|
#endif |
|
|
|
if ((wait_state != TASK_RUNNING || |
|
(call_cond_resched && !reacquire_locks) || |
|
(alloc_pages_nr && gfpflags_allow_blocking(alloc_pages_gfp))) && |
|
(test_disable_irq || disable_softirq || disable_preempt || |
|
lock_rcu || lock_spinlock_ptr || lock_rwlock_ptr)) { |
|
pr_err("refuse to sleep in atomic context\n"); |
|
return -EINVAL; |
|
} |
|
|
|
if (lock_mmap_sem && !main_task->mm) { |
|
pr_err("no mm to lock mmap_lock\n"); |
|
return -EINVAL; |
|
} |
|
|
|
if (test_file_path[0]) { |
|
test_file = filp_open(test_file_path, O_RDONLY, 0); |
|
if (IS_ERR(test_file)) { |
|
pr_err("failed to open %s: %ld\n", test_file_path, PTR_ERR(test_file)); |
|
return PTR_ERR(test_file); |
|
} |
|
test_inode = file_inode(test_file); |
|
} else if (test_lock_inode || |
|
test_lock_mapping || |
|
test_lock_sb_umount) { |
|
pr_err("no file to lock\n"); |
|
return -EINVAL; |
|
} |
|
|
|
if (test_lock_inode && test_inode) |
|
lock_rwsem_ptr = (unsigned long)&test_inode->i_rwsem; |
|
|
|
if (test_lock_mapping && test_file && test_file->f_mapping) |
|
lock_rwsem_ptr = (unsigned long)&test_file->f_mapping->i_mmap_rwsem; |
|
|
|
if (test_lock_sb_umount && test_inode) |
|
lock_rwsem_ptr = (unsigned long)&test_inode->i_sb->s_umount; |
|
|
|
pr_notice("START pid=%d time=%u +%u ns cooldown=%u +%u ns iterations=%u state=%s %s%s%s%s%s%s%s%s%s%s%s\n", |
|
main_task->pid, time_secs, time_nsecs, |
|
cooldown_secs, cooldown_nsecs, iterations, state, |
|
all_cpus ? "all_cpus " : "", |
|
iowait ? "iowait " : "", |
|
test_disable_irq ? "disable_irq " : "", |
|
disable_softirq ? "disable_softirq " : "", |
|
disable_preempt ? "disable_preempt " : "", |
|
lock_rcu ? "lock_rcu " : "", |
|
lock_read ? "lock_read " : "", |
|
touch_softlockup ? "touch_softlockup " : "", |
|
touch_hardlockup ? "touch_hardlockup " : "", |
|
call_cond_resched ? "call_cond_resched " : "", |
|
reacquire_locks ? "reacquire_locks " : ""); |
|
|
|
if (alloc_pages_nr) |
|
pr_notice("ALLOCATE PAGES nr=%u order=%u gfp=%pGg %s\n", |
|
alloc_pages_nr, alloc_pages_order, &alloc_pages_gfp, |
|
reallocate_pages ? "reallocate_pages " : ""); |
|
|
|
if (all_cpus) { |
|
unsigned int cpu; |
|
|
|
cpus_read_lock(); |
|
|
|
preempt_disable(); |
|
master_cpu = smp_processor_id(); |
|
for_each_online_cpu(cpu) { |
|
INIT_WORK(per_cpu_ptr(&test_works, cpu), test_work_fn); |
|
queue_work_on(cpu, system_highpri_wq, |
|
per_cpu_ptr(&test_works, cpu)); |
|
} |
|
preempt_enable(); |
|
|
|
for_each_online_cpu(cpu) |
|
flush_work(per_cpu_ptr(&test_works, cpu)); |
|
|
|
cpus_read_unlock(); |
|
} else { |
|
test_lockup(true); |
|
} |
|
|
|
if (measure_lock_wait) |
|
pr_notice("Maximum lock wait: %lld ns\n", |
|
atomic64_read(&max_lock_wait)); |
|
|
|
if (alloc_pages_nr) |
|
pr_notice("Page allocation failed %u times\n", |
|
atomic_read(&alloc_pages_failed)); |
|
|
|
pr_notice("FINISH in %llu ns\n", local_clock() - test_start); |
|
|
|
if (test_file) |
|
fput(test_file); |
|
|
|
if (signal_pending(main_task)) |
|
return -EINTR; |
|
|
|
return -EAGAIN; |
|
} |
|
module_init(test_lockup_init); |
|
|
|
MODULE_LICENSE("GPL"); |
|
MODULE_AUTHOR("Konstantin Khlebnikov <[email protected]>"); |
|
MODULE_DESCRIPTION("Test module to generate lockups");
|
|
|