Re: [RFC PATCH 0/7] locking/rtqspinlock: Realtime queued spinlocks

[Daniel Bristot de Oliveira]

On 01/04/2017 04:25 PM, Waiman Long wrote:
>> OK, so a single numerical field isn't sufficient to describe priority
>> anymore, since we added DEADLINE support things have gotten a lot more
>> complex.
> From what I read from the code, DL tasks all have the same priority that
> is higher than any of the RT tasks. So you mean DL tasks have other
> property that kind of categorizing them into different sub-priorities
> that is not being reflected in their priority level. Is that right?

DL tasks are scheduled according to their absolute deadline, which
stored in the u64 curr->dl.deadline.

It is more complex because the priority of a deadline task is always
changing. The priority of a DL task changes on every new
periodic/sporadic replenishment/activation.


-- Daniel