Hello to the list,
I got a question about spinlocks. Here is some pseudo-code:
my_external_int_handler(...)
{
spin_lock(&my_lock);
// do things...
spin_unlock(&my_lock);
}
my_ioctl_handler(ioctl_value)
{
switch(ioctl_value)
{
case xy:
spin_lock_irqsave(&my_lock, flags);
// do stuff
spin_unlock_irqsave(&my_lock, flags);
break;
}
}
I just wan't to ensure that the interrupt is finished before I handle
the IOCTL request, so that I'm not running into a race condition that
would a affect an ring buffer.
But what happens when an interrupt signal is triggered at the external
interrupt pin, does spin_lock_irqsave que the interrupt? Or does it
dismiss the interrupt? Does spinlock_irqsave mean I would miss an
interrupt? If so, spinlock won't be the right thing to do...
What I need is something like:
while(interrupt_working){ sleep(); }
How to do right?
Kind regards,
Ole
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