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Message-ID: <5886464d-a867-471e-858e-b4ed732a1d76@web.de>
Date: Thu, 9 May 2024 10:16:15 +0200
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Subject: Re: [PATCH v3] time/tick-sched: idle load balancing when nohz_full
 cpu becomes idle.
To: Yun Levi <ppbuk5246@gmail.com>, kernel-janitors@vger.kernel.org,
 Anna-Maria Behnsen <anna-maria@linutronix.de>,
 Frederic Weisbecker <frederic@kernel.org>, Ingo Molnar <mingo@kernel.org>,
 Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>
References: <20240508172621.30069-1-ppbuk5246@gmail.com>
 <20240508192213.31050-1-ppbuk5246@gmail.com>
 <a407d12f-6845-4f51-a112-6bdc17641ff1@web.de>
 <CAM7-yPS6ecODhv-FQpYE5OE_LufmtKRg4htp9JH6MBUF03N4rA@mail.gmail.com>
Content-Language: en-GB
From: Markus Elfring <Markus.Elfring@web.de>
In-Reply-To: <CAM7-yPS6ecODhv-FQpYE5OE_LufmtKRg4htp9JH6MBUF03N4rA@mail.gmail.com>
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>>> +++ b/kernel/time/tick-sched.c
>>> @@ -1228,8 +1228,10 @@ void tick_nohz_idle_stop_tick(void)
>>>               ts->idle_sleeps++;
>>>               ts->idle_expires =3D expires;
>>>
>>> -             if (!was_stopped && tick_sched_flag_test(ts, TS_FLAG_STO=
PPED)) {
>>> -                     ts->idle_jiffies =3D ts->last_jiffies;
>>> +             if (tick_sched_flag_test(ts, TS_FLAG_STOPPED)) {
>>> +                     if (!was_stopped)
>>> +                             ts->idle_jiffies =3D ts->last_jiffies;
>>> +
>>>                       nohz_balance_enter_idle(cpu);
>>>               }
=E2=80=A6
> So, I think it's enough in commit message?
=E2=80=A6

We are trying to clarify special implementation details here.
Our corresponding wording preferences are probably different.
I hope that a better common understanding can be achieved also for
another transformation.

* Thus I became curious how you got interested to adjust this software
  component further.

* Will any other data representation become more helpful for the circumsta=
nces
  according to calls of a function like =E2=80=9Ctick_nohz_idle_stop_tick=
=E2=80=9D?

* How do you think about to stress condition ordering concerns around
  the system configuration =E2=80=9Cnohz_full=E2=80=9D?

* How will related changelogs evolve further?


Regards,
Markus