Re: [PATCH 1/6] sched/proxy: Remove superfluous clear_task_blocked_in()

[K Prateek Nayak]

Hello John,

On 5/29/2026 12:44 PM, John Stultz wrote:
> You see these things so quickly! :)  Beat me sending out my own
> analysis (which is maybe a slightly different case, but still).

That was an interesting case too! My brain defaults to one lock and two
CPUs but your brain goes a few step (and a few locks, CPUs) further ;-)

>> Part of that belongs in commit e2ff8b7bde07 ("sched/proxy: Only return
>> migrate when needed") and the first hunk of 83f9b04ef50c ("sched/proxy:
>> Switch proxy to use p->is_blocked") in proxy_needs_return() should be
>> dropped.
> 
> Very nice, yes this does help when the "Only return migrate when
> needed" is added!
> 
> So I've included this and reworked the order of Peter's doodles slightly to be:
>   sched/proxy: Optimize try_to_wake_up()
>   sched: Be more strict about p->is_blocked
>   sched/proxy: Only return migrate when needed
>   FOLD: k prateek's fixup
>   sched/proxy: Switch proxy to use p->is_blocked
>   sched/proxy: Remove PROXY_WAKING
>   sched/proxy: Remove superfluous clear_task_blocked_in()
>   sched: Simplify ttwu_runnable()

Ack! That should cover all bases.

> 
> Which seems to be working at each step.  Though I've only lightly
> tested and I didn't trip this initially with the series, so more
> testing will be needed tommorow.

Meanwhile, I'll rearrange the patches like you suggested above and run
some testes too. Fingers crossed

-- 
Thanks and Regards,
Prateek