Re: waiting for irq from userland?

H. Peter Anvin (hpa@transmeta.com)
26 Jul 1999 04:57:48 GMT


Followup to: <379A76E6.8E4E2856@pobox.com>
By author: Jeff Garzik <jgarzik@pobox.com>
In newsgroup: linux.dev.kernel
>
> What is the most efficient way to wait for a device interrupt from
> userland, if you control both the device driver and the application?
> SysV semaphore? Signal?
>

Blocking I/O. Use an I/O system call -- any system call (read, write,
ioctl) -- and have that put the process on a wait queue. Your
interrupt routine then wakes up the queue.

-hpa

-- 
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