On Wed, Apr 13, 2016 at 03:56:51PM +0200, Frederic Weisbecker wrote:
> @@ -4645,11 +4674,11 @@ void cpu_load_update_nohz(int active)
> void cpu_load_update_active(struct rq *this_rq)
> {
> unsigned long load = weighted_cpuload(cpu_of(this_rq));
> - /*
> - * See the mess around cpu_load_update_idle() / cpu_load_update_nohz().
> - */
> - this_rq->last_load_update_tick = jiffies;
> - __cpu_load_update(this_rq, load, 1, 1);
> +
> + if (tick_nohz_tick_stopped())
> + cpu_load_update_nohz(this_rq, READ_ONCE(jiffies), load);
> + else
> + cpu_load_update_periodic(this_rq, load);
Considering it further, I wonder if needing it.
(Sorry if I missed something.)
Case 1. tickless -> (scheduler_tick) -> tickless
I am not sure for this case if the rq's load can be changed or not,
especially, if the rq's load can be changed *at this point*.
Please remind that the load[0] is set here.
Case 2. tickless -> (scheduler_tick) -> restart tick
Will be done by the tick restart routine when exiting irq.
-> no problem.
Case 3. tick -> (scheduler_tick) -> tickless
Same as before.
-> no problem.
Case 4. tick -> (scheduler_tick) -> tick
We can rely on regular schedule_tick().
-> no problem.
