Messages in this thread | | | From | "Rafael J. Wysocki" <> | Subject | Re: [PATCH V2 3/4] cpufreq: schedutil: move slow path from workqueue to SCHED_FIFO task | Date | Thu, 24 Nov 2016 02:19:03 +0100 |
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On Wednesday, November 16, 2016 04:26:05 PM Peter Zijlstra wrote: > On Tue, Nov 15, 2016 at 01:53:22PM +0530, Viresh Kumar wrote: > > @@ -308,7 +313,21 @@ static void sugov_irq_work(struct irq_work *irq_work) > > struct sugov_policy *sg_policy; > > > > sg_policy = container_of(irq_work, struct sugov_policy, irq_work); > > + > > + /* > > + * For Real Time and Deadline tasks, schedutil governor shoots the > > + * frequency to maximum. And special care must be taken to ensure that > > + * this kthread doesn't result in that. > > + * > > + * This is (mostly) guaranteed by the work_in_progress flag. The flag is > > + * updated only at the end of the sugov_work() and before that schedutil > > + * rejects all other frequency scaling requests. > > + * > > + * Though there is a very rare case where the RT thread yields right > > + * after the work_in_progress flag is cleared. The effects of that are > > + * neglected for now. > > + */ > > + kthread_queue_work(&sg_policy->worker, &sg_policy->work); > > } > > > Right, so that's a wee bit icky, but its also entirely pre-existing > code. > > Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Whole series applied.
Thanks, Rafael
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