Re: [PATCH] irqdev: remove tot_num_intr

[Samuel Thibault]

Junling Ma, le mar. 04 août 2020 14:47:09 -0700, a ecrit:
> The tot_num_intr field is a count of how many deliverable interrupts across 
> all lines. When we move
> to the scheme of blocking read for request and write for acking, it is 
> possible that an interrupt
> can happen during a small period that the interrupt is acked, but the read 
> has not happended yet.

As discussed on IRC, this is rather a problem of the device_read/write
concept, that would require device_read() to be called before the
interrupt raises, just because on the kernel side the mach_device_t is
the same for all userland processes sharing the IRQ. I don't think it's
a path we want to follow, and we'd rather use register/ack IPC like we
have now.

Samuel