int raw_spin_trylock_n_irqsave(raw_spinlock_t *lock, unsigned long *flags, struct seq_file *m, char *msg){
int locked, trylock_cnt=0;
do{
locked = raw_spin_trylock_irqsave(lock, *flags);
trylock_cnt++;
mdelay(10);
}while((!locked) && (trylock_cnt < TRYLOCK_NUM));
if (!locked){
struct task_struct *owner = NULL;
SEQ_printf(m, "Warning: fail to get lock in %s\n", msg);
#ifdef CONFIG_DEBUG_SPINLOCK
if (lock->owner && lock->owner != SPINLOCK_OWNER_INIT )
owner = lock->owner;
SEQ_printf(m, " lock: %p, .magic: %08x, .owner: %s/%d, "
".owner_cpu: %d, value: %d\n",
lock, lock->magic,
owner ? owner-> comm: "<<none>>",
owner ? task_pid_nr(owner): -1,
lock->owner_cpu, lock->raw_lock.lock);
#endif
}
return locked;
}
/* IAMROOT-12AB:
* -------------
* 함수 결과가 1인 경우 계속 진행한다는 의미
*/
int ___ratelimit(struct ratelimit_state *rs, const char *func)
{
unsigned long flags;
int ret;
/* IAMROOT-12AB:
* -------------
* interval이 0으로 설정되면 제한 없이 계속 진행한다는 의미
*/
if (!rs->interval)
return 1;
/*
* If we contend on this state's lock then almost
* by definition we are too busy to print a message,
* in addition to the one that will be printed by
* the entity that is holding the lock already:
*/
if (!raw_spin_trylock_irqsave(&rs->lock, flags))
return 0;
/* IAMROOT-12AB:
* -------------
* begin이 0인 경우 bigin에 현재 jiffies를 기록한다.
*/
if (!rs->begin)
rs->begin = jiffies;
/* IAMROOT-12AB:
* ------------ -
* interval 이후에는 missed 카운트가 발생한 경우 정산하여 출력한다.
* (출력시에 더 이상 호출을 포기한 callback 함수명과 missed 카운트를 나타낸다)
*/
if (time_is_before_jiffies(rs->begin + rs->interval)) {
if (rs->missed)
printk(KERN_WARNING "%s: %d callbacks suppressed\n",
func, rs->missed);
rs->begin = 0;
rs->printed = 0;
rs->missed = 0;
}
/* IAMROOT-12AB:
* -------------
* 정상 호출 시 printed가 증가되고, 그렇지 않은 경우 missed가 증가된다.
*/
if (rs->burst && rs->burst > rs->printed) {
rs->printed++;
ret = 1;
} else {
rs->missed++;
ret = 0;
}
raw_spin_unlock_irqrestore(&rs->lock, flags);
return ret;
}
void resched_cpu(int cpu)
{
struct rq *rq = cpu_rq(cpu);
unsigned long flags;
if (!raw_spin_trylock_irqsave(&rq->lock, flags))
return;
resched_task(cpu_curr(cpu));
raw_spin_unlock_irqrestore(&rq->lock, flags);
}
int anon_rwsem_is_locked(struct rw_anon_semaphore *sem)
{
int ret = 1;
unsigned long flags;
if (raw_spin_trylock_irqsave(&sem->wait_lock, flags)) {
ret = (sem->activity != 0);
raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
}
return ret;
}
/*
* __ratelimit - rate limiting
* @rs: ratelimit_state data
* @func: name of calling function
*
* This enforces a rate limit: not more than @rs->burst callbacks
* in every @rs->interval
*
* RETURNS:
* 0 means callbacks will be suppressed.
* 1 means go ahead and do it.
*/
int ___ratelimit(struct ratelimit_state *rs, const char *func)
{
unsigned long flags;
int ret;
if (!rs->interval)
return 1;
/*
* If we contend on this state's lock then almost
* by definition we are too busy to print a message,
* in addition to the one that will be printed by
* the entity that is holding the lock already:
*/
if (!raw_spin_trylock_irqsave(&rs->lock, flags))
return 0;
if (!rs->begin)
rs->begin = jiffies;
if (time_is_before_jiffies(rs->begin + rs->interval)) {
if (rs->missed)
printk(KERN_WARNING "%s: %d callbacks suppressed\n",
func, rs->missed);
rs->begin = 0;
rs->printed = 0;
rs->missed = 0;
}
if (rs->burst && rs->burst > rs->printed) {
rs->printed++;
ret = 1;
} else {
rs->missed++;
ret = 0;
}
raw_spin_unlock_irqrestore(&rs->lock, flags);
return ret;
}
