Re: [2.4.17/18pre] VM and swap - it's really unusable

Momchil Velikov
2002-01-14T22:34:44Z

>>>>> "Alan" == Alan Cox <alan@lxorguk.ukuu.org.uk> writes:

Oliver> You can have an rt task block on a lock held by a normal task that was
Oliver> preempted by a rt task of lower priority. The same problem as with the
Oliver> sched_idle patches.
>>
>> This can happen with a non-preemptible kernel too. And it has nothing to
>> do with scheduling policy.

Alan> So why bother adding pre-emption. As you keep saying - it doesnt
Alan> gain anything

Nope. I don't. I said (at least in the above) it didn't hurt.

One can consider a non-preemptible kernel as a special kind of
priority inversion, preemptible kernel will eliminate _that_ case of
priority inversion.

Regards,
-velco