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Message-ID: <0928660b39aea2828a79a87fef57447e657d43b4.camel@linux.intel.com>
Subject: Re: [PATCH] tick-sched: fix idle and iowait sleeptime accounting vs
 CPU hotplug
From: Tim Chen <tim.c.chen@linux.intel.com>
To: Heiko Carstens <hca@linux.ibm.com>, Frederic Weisbecker
	 <frederic@kernel.org>, Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar
	 <mingo@kernel.org>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>, Alexander Gordeev
	 <agordeev@linux.ibm.com>, Vasily Gorbik <gor@linux.ibm.com>, 
	linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org
Date: Mon, 22 Jan 2024 10:19:30 -0800
In-Reply-To: <20240115163555.1004144-1-hca@linux.ibm.com>
References: <20240115163555.1004144-1-hca@linux.ibm.com>
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On Mon, 2024-01-15 at 17:35 +0100, Heiko Carstens wrote:
>=20
> =20
> +	idle_sleeptime =3D ts->idle_sleeptime;
> +	iowait_sleeptime =3D ts->iowait_sleeptime;
>  	memset(ts, 0, sizeof(*ts));
> +	ts->idle_sleeptime =3D idle_sleeptime;
> +	ts->iowait_sleeptime =3D iowait_sleeptime;
>  }

Should idle_calls and idle_sleeps be preserved and
restored too? =C2=A0

Seems like if we preserve the
idle_sleeptime, and wish to compute the average
sleep time per sleep, we will need to know the value of
idle_sleeps that's also preserved across CPU offline/online.

Tim