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From: Xuewen Yan <xuewen.yan94@gmail.com>
Date: Wed, 21 Feb 2024 19:00:55 +0800
Message-ID: <CAB8ipk9FtgYh5Ho-nFQCwUO8zOPEk73VS0KHFDuRS9yxDRpe4A@mail.gmail.com>
Subject: Re: [PATCH] workqueue: Control the frequency of intensive warning
 through cmdline
To: Tejun Heo <tj@kernel.org>
Cc: Xuewen Yan <xuewen.yan@unisoc.com>, jiangshanlai@gmail.com, corbet@lwn.net, 
	paulmck@kernel.org, rdunlap@infradead.org, peterz@infradead.org, 
	yanjiewtw@gmail.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, 
	ke.wang@unisoc.com
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Hi Tejun

On Wed, Feb 21, 2024 at 1:44=E2=80=AFPM Tejun Heo <tj@kernel.org> wrote:
>
> Hello,
>
> On Wed, Feb 21, 2024 at 10:01:17AM +0800, Xuewen Yan wrote:
> >                 cnt =3D atomic64_inc_return_relaxed(&ent->cnt);
> > -               if (cnt >=3D 4 && is_power_of_2(cnt))
> > +               if (cnt =3D=3D wq_cpu_intensive_warning_nth ||
> > +                   (cnt > wq_cpu_intensive_warning_nth && is_power_of_=
2(cnt)))
>
> If we do this the nth name doesn't really make sense. Maybe something lik=
e
> wq_cpu_intensive_warning_thresh is better? Also, something like the
> following might be more predictable. Let's say
> wq_cpu_intensive_warning_thresh of 0 disables the warnings and it's
> initialized to 4 by default.
>
>         if (cnt >=3D wq_cpu_intensive_warning_thresh &&
>             is_power_of_2(cnt + 1 - wq_cpu_intensive_warning_thresh))
>

This way looks simpler, but it could not disable the warnings, but I
think this is okay, because even if the threshold is set to 0, the
warning will only be printed when 1, 3, 7, 15....

I will send patch-v2 later as you suggested:)

Thanks.
BR

--
xuewen