C++ raw_spin_unlock_irq函数代码示例

static void s2idle_enter(void)
{
	trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_TO_IDLE, true);

	raw_spin_lock_irq(&s2idle_lock);
	if (pm_wakeup_pending())
		goto out;

	s2idle_state = S2IDLE_STATE_ENTER;
	raw_spin_unlock_irq(&s2idle_lock);

	get_online_cpus();
	cpuidle_resume();

	/* Push all the CPUs into the idle loop. */
	wake_up_all_idle_cpus();
	/* Make the current CPU wait so it can enter the idle loop too. */
	swait_event_exclusive(s2idle_wait_head,
		    s2idle_state == S2IDLE_STATE_WAKE);

	cpuidle_pause();
	put_online_cpus();

	raw_spin_lock_irq(&s2idle_lock);

 out:
	s2idle_state = S2IDLE_STATE_NONE;
	raw_spin_unlock_irq(&s2idle_lock);

	trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_TO_IDLE, false);
}

/*
 *	handle_nested_irq - Handle a nested irq from a irq thread
 *	@irq:	the interrupt number
 *
 *	Handle interrupts which are nested into a threaded interrupt
 *	handler. The handler function is called inside the calling
 *	threads context.
 */
void handle_nested_irq(unsigned int irq)
{
	struct irq_desc *desc = irq_to_desc(irq);
	struct irqaction *action;
	irqreturn_t action_ret;

	might_sleep();

	raw_spin_lock_irq(&desc->lock);

	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
	kstat_incr_irqs_this_cpu(irq, desc);

	action = desc->action;
	if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) {
		desc->istate |= IRQS_PENDING;
		goto out_unlock;
	}

	irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
	raw_spin_unlock_irq(&desc->lock);

	action_ret = action->thread_fn(action->irq, action->dev_id);
	if (!noirqdebug)
		note_interrupt(irq, desc, action_ret);

	raw_spin_lock_irq(&desc->lock);
	irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);

out_unlock:
	raw_spin_unlock_irq(&desc->lock);
}

static int stlog_print(char __user *buf, int size)
{
	char *text;
	struct ringbuf *msg;
	int len = 0;

	#ifdef	DEBUG_STLOG
	printk("[STLOG] %s stlog_seq %llu stlog_idx %lu ringbuf_first_seq %llu ringbuf_first_idx %lu ringbuf_next_seq %llu ringbuf_next_idx %lu \n",
			__func__,stlog_seq,stlog_idx,ringbuf_first_seq,ringbuf_first_idx,ringbuf_next_seq,ringbuf_next_idx);
	#endif
	
	text = kmalloc(RINGBUF_LINE_MAX + S_PREFIX_MAX, GFP_KERNEL);
	if (!text)
		return -ENOMEM;

	while (size > 0) {
		size_t n;

		raw_spin_lock_irq(&ringbuf_lock);
		if (stlog_seq < ringbuf_first_seq) {
			/* messages are gone, move to first one */
			stlog_seq = ringbuf_first_seq;
			stlog_idx = ringbuf_first_idx;
			ringbuf_prev = 0;
		}
		if (stlog_seq == ringbuf_next_seq) {
			raw_spin_unlock_irq(&ringbuf_lock);
			break;
		}

		msg = ringbuf_from_idx(stlog_idx);
		n = stlog_print_text(msg, ringbuf_prev, false, text, RINGBUF_LINE_MAX + S_PREFIX_MAX);
		if (n <= size) {
			/* message fits into buffer, move forward */
			stlog_idx = ringbuf_next(stlog_idx);
			stlog_seq++;
			ringbuf_prev = msg->flags;
		} else if (!len){
			n = size;
		} else
			n = 0;
		raw_spin_unlock_irq(&ringbuf_lock);

		if (!n)
			break;

		if (copy_to_user(buf, text, n)) {
			if (!len)
				len = -EFAULT;
			break;
		}

		len += n;
		size -= n;
		buf += n;
	}

	kfree(text);
	return len;
}

static inline int set_sysint1_assign(unsigned int irq, unsigned char assign)
{
	struct irq_desc *desc = irq_to_desc(irq);
	uint16_t intassign0, intassign1;
	unsigned int pin;

	pin = SYSINT1_IRQ_TO_PIN(irq);

	raw_spin_lock_irq(&desc->lock);

	intassign0 = icu1_read(INTASSIGN0);
	intassign1 = icu1_read(INTASSIGN1);

	switch (pin) {
	case 0:
		intassign0 &= ~INTASSIGN_MASK;
		intassign0 |= (uint16_t)assign;
		break;
	case 1:
		intassign0 &= ~(INTASSIGN_MASK << 3);
		intassign0 |= (uint16_t)assign << 3;
		break;
	case 2:
		intassign0 &= ~(INTASSIGN_MASK << 6);
		intassign0 |= (uint16_t)assign << 6;
		break;
	case 3:
		intassign0 &= ~(INTASSIGN_MASK << 9);
		intassign0 |= (uint16_t)assign << 9;
		break;
	case 8:
		intassign0 &= ~(INTASSIGN_MASK << 12);
		intassign0 |= (uint16_t)assign << 12;
		break;
	case 9:
		intassign1 &= ~INTASSIGN_MASK;
		intassign1 |= (uint16_t)assign;
		break;
	case 11:
		intassign1 &= ~(INTASSIGN_MASK << 6);
		intassign1 |= (uint16_t)assign << 6;
		break;
	case 12:
		intassign1 &= ~(INTASSIGN_MASK << 9);
		intassign1 |= (uint16_t)assign << 9;
		break;
	default:
		raw_spin_unlock_irq(&desc->lock);
		return -EINVAL;
	}

	sysint1_assign[pin] = assign;
	icu1_write(INTASSIGN0, intassign0);
	icu1_write(INTASSIGN1, intassign1);

	raw_spin_unlock_irq(&desc->lock);

	return 0;
}

/*****************************************************************************
函数名称  : mlog_log_read
功能描述  :
输入参数  :
输出参数  :
返 回 值  : No
修改历史  :
*****************************************************************************/
static ssize_t mlog_log_read(struct file *file, char __user *buf,size_t count, loff_t *ppos)
{
    ssize_t ret = -EINVAL;
    int error = 0;
    int i = 0;
    int bwr_eq_rd = 0;
    char c;
    DEFINE_WAIT(wait);

    for (;;) {
        prepare_to_wait(&mlog_log_wait, &wait, TASK_INTERRUPTIBLE);

        raw_spin_lock_irq(&mlog_log_buf_lock);
        bwr_eq_rd = (log_wr_off == log_rd_off);
        raw_spin_unlock_irq(&mlog_log_buf_lock);
        if (!bwr_eq_rd)
        {
            break;
        }

        if (file->f_flags & O_NONBLOCK)
        {
            ret = -EAGAIN;
            break;
        }

        if (signal_pending(current))
        {
            ret = -EINTR;
            break;
        }
        schedule();
    }
    finish_wait(&mlog_log_wait, &wait);

    if (bwr_eq_rd)
    {
        return ret;
    }

    raw_spin_lock_irq(&mlog_log_buf_lock);
    i = 0;

    while (!error && (log_wr_off != log_rd_off) && i < count) {
        c = LOG_BUF(log_rd_off);
        log_rd_off++;
        error = __put_user(c,buf);
        buf++;
        i++;
    }

    if (!error) {
        ret = i;
    }
    raw_spin_unlock_irq(&mlog_log_buf_lock);

    return ret;
}

/*
 * This function is protected against re-entrancy.
 */
void die(const char *str, struct pt_regs *regs, int err)
{
	enum bug_trap_type bug_type = BUG_TRAP_TYPE_NONE;
	struct thread_info *thread = current_thread_info();
	int ret;

	oops_enter();

	raw_spin_lock_irq(&die_lock);
	console_verbose();
	bust_spinlocks(1);

	if (!user_mode(regs))
		bug_type = report_bug(regs->pc, regs);
	if (bug_type != BUG_TRAP_TYPE_NONE)
		str = "Oops - BUG";

	ret = __die(str, err, thread, regs);

	if (regs && kexec_should_crash(thread->task))
		crash_kexec(regs);

	bust_spinlocks(0);
	add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
	raw_spin_unlock_irq(&die_lock);
	oops_exit();

	if (in_interrupt())
		panic("Fatal exception in interrupt");
	if (panic_on_oops)
		panic("Fatal exception");
	if (ret != NOTIFY_STOP)
		do_exit(SIGSEGV);
}

/*
 * This function is protected against re-entrancy.
 */
void die(const char *str, struct pt_regs *regs, int err)
{
	struct thread_info *thread = current_thread_info();
	int ret;

	oops_enter();

	raw_spin_lock_irq(&die_lock);
	console_verbose();
	bust_spinlocks(1);
	ret = __die(str, err, thread, regs);

	if (regs && kexec_should_crash(thread->task))
		crash_kexec(regs);

	bust_spinlocks(0);
	add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
	raw_spin_unlock_irq(&die_lock);
	oops_exit();

	if (in_interrupt())
		panic("Fatal exception in interrupt");
	if (panic_on_oops)
		panic("Fatal exception");
	if (ret != NOTIFY_STOP)
		do_exit(SIGSEGV);
}

/*
 * Because this function is inlined, the 'state' parameter will be
 * constant, and thus optimised away by the compiler.  Likewise the
 * 'timeout' parameter for the cases without timeouts.
 */
static inline int __sched __down_common(struct semaphore *sem, long state,
								long timeout)
{
	struct semaphore_waiter waiter;

	list_add_tail(&waiter.list, &sem->wait_list);
	waiter.task = current;
	waiter.up = false;

	for (;;) {
		if (signal_pending_state(state, current))
			goto interrupted;
		if (unlikely(timeout <= 0))
			goto timed_out;
		__set_current_state(state);
		raw_spin_unlock_irq(&sem->lock);
		timeout = schedule_timeout(timeout);
		raw_spin_lock_irq(&sem->lock);
		if (waiter.up)
			return 0;
	}

 timed_out:
	list_del(&waiter.list);
	return -ETIME;

 interrupted:
	list_del(&waiter.list);
	return -EINTR;
}

/**
 *	probe_irq_on	- begin an interrupt autodetect
 *
 *	Commence probing for an interrupt. The interrupts are scanned
 *	and a mask of potential interrupt lines is returned.
 *
 */
unsigned long probe_irq_on(void)
{
	struct irq_desc *desc;
	unsigned long mask = 0;
	int i;

	/*
	 * quiesce the kernel, or at least the asynchronous portion
	 */
	async_synchronize_full();
	mutex_lock(&probing_active);
	/*
	 * something may have generated an irq long ago and we want to
	 * flush such a longstanding irq before considering it as spurious.
	 */
	for_each_irq_desc_reverse(i, desc) {
		raw_spin_lock_irq(&desc->lock);
		if (!desc->action && irq_settings_can_probe(desc)) {
			/*
			 * Some chips need to know about probing in
			 * progress:
			 */
			if (desc->irq_data.chip->irq_set_type)
				desc->irq_data.chip->irq_set_type(&desc->irq_data,
							 IRQ_TYPE_PROBE);
			irq_startup(desc, false);
		}
		raw_spin_unlock_irq(&desc->lock);
	}

/*
 * It is not legal to sleep in the idle task - print a warning
 * message if some code attempts to do it:
 */
static void
dequeue_task_idle(struct rq *rq, struct task_struct *p, int flags)
{
	raw_spin_unlock_irq(&rq->lock);
	printk(KERN_ERR "bad: scheduling from the idle thread!\n");
	dump_stack();
	raw_spin_lock_irq(&rq->lock);
}

	/*
	 * enable any unassigned irqs
	 * (we must startup again here because if a longstanding irq
	 * happened in the previous stage, it may have masked itself)
	 */
	for_each_irq_desc_reverse(i, desc) {
		raw_spin_lock_irq(&desc->lock);
		if (!desc->action && irq_settings_can_probe(desc)) {
			desc->istate |= IRQS_AUTODETECT | IRQS_WAITING;
			if (irq_startup(desc, false))
				desc->istate |= IRQS_PENDING;
		}
		raw_spin_unlock_irq(&desc->lock);
	}

/**
 * pci_cfg_access_lock - Lock PCI config reads/writes
 * @dev:	pci device struct
 *
 * When access is locked, any userspace reads or writes to config
 * space and concurrent lock requests will sleep until access is
 * allowed via pci_cfg_access_unlock() again.
 */
void pci_cfg_access_lock(struct pci_dev *dev)
{
	might_sleep();

	raw_spin_lock_irq(&pci_lock);
	if (dev->block_cfg_access)
		pci_wait_cfg(dev);
	dev->block_cfg_access = 1;
	raw_spin_unlock_irq(&pci_lock);
}

static noinline void pci_wait_cfg(struct pci_dev *dev)
{
	DECLARE_WAITQUEUE(wait, current);

	init_waitqueue_head(&wait);

	do {
		raw_spin_unlock_irq(&pci_lock);
		vmm_completion_wait(&__pci_cfg_completion);
		raw_spin_lock_irq(&pci_lock);
	} while (dev->block_cfg_access);
}

static ssize_t hwirq_show(struct kobject *kobj,
			  struct kobj_attribute *attr, char *buf)
{
	struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
	ssize_t ret = 0;

	raw_spin_lock_irq(&desc->lock);
	if (desc->irq_data.domain)
		ret = sprintf(buf, "%d\n", (int)desc->irq_data.hwirq);
	raw_spin_unlock_irq(&desc->lock);

	return ret;
}

static noinline void pci_wait_cfg(struct pci_dev *dev)
{
	DECLARE_WAITQUEUE(wait, current);

	__add_wait_queue(&pci_cfg_wait, &wait);
	do {
		set_current_state(TASK_UNINTERRUPTIBLE);
		raw_spin_unlock_irq(&pci_lock);
		schedule();
		raw_spin_lock_irq(&pci_lock);
	} while (dev->block_cfg_access);
	__remove_wait_queue(&pci_cfg_wait, &wait);
}