Re: [PATCH] sched/rt: Move cpu rq properties from "struct rt_rq" to "struct rq"

[Kirill Tkhai <tkhai@yandex.ru>]

21.12.2012, 03:07, "Steven Rostedt" <rostedt@goodmis.org>:
> On Fri, 2012-12-21 at 02:16 +0400, Kirill Tkhai wrote:
>
>>  20.12.2012, 21:53, "Thomas Gleixner" <tglx@linutronix.de>:
>>>  On Tue, 18 Dec 2012, Kirill Tkhai wrote:
>>>>   The members rt_nr_total, rt_nr_migratory, overloaded and pushable_tasks are
>>>>   properties of cpu runqueue, not group rt_rq.
>>>  Why?
>>  Because, they depend on number and properties of all processes of rq, not of nested rt_rq.
>
> You're answer is still confusing.
>
>         struct rq {
>                 [...]
>                 struct rt_rq rt;
>
> rt_rq is just a part of rq. What's the point?
>
>         rq = container_of(rt_rq, struct rt_rq, rt);
>
> As the comment above struct rt_rq says:
>
> /* Real-Time classes' related field in a runqueue: */
>
> Those look like fields related to the Real-Time class. I don't see them
> used outside of kernel/sched/rt.c
>
                                    
           entity_1->my_q_1
           /                        
          /                         
rq->rt  -entity_2->my_q_2
          \                          
           \                           
             entity_n->my_q_n
                                        

I say about child rt_rqs (my_q_1....my_q_n). They don't have rt_nr_total, rt_nr_migratory, overloaded and pushable_tasks.
The only use of overloaded, for example, is "rq->rt.overloaded". The same with other variables.

Kirill


> -- Steve
>
>>>  Thanks,
>>>
>>>          tglx