Re: scheduler ignores need_resched flag in 2.2.x and 2.3.x?

From: Jamie Lokier (lk@tantalophile.demon.co.uk)
Date: Tue Mar 21 2000 - 17:55:58 EST


Jamie Lokier wrote:
> For it to loop, you need it to happen repeatedly. It must be a rapid
> cascade of interrupts waking up successively higher priority tasks.
> Each interrupt has to arrive exactly a few cycles before the previous
> interrupt handler is about to return to userspace -- if that's
> happening, userspace is already broken.

I forgot to mention "and the interrupt handlers must be reenabling
interrupts on the exit path so all the interrupts are nested -- which
means your kernel stack is getting trashed too".

So don't worry about loops.

-- Jamie

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Thu Mar 23 2000 - 21:00:34 EST