From: Andi Kleen <ak@linux.intel.com>
To: paulmck@kernel.org, Chao Gao <chao.gao@intel.com>
Cc: Feng Tang <feng.tang@intel.com>,
kernel test robot <oliver.sang@intel.com>,
John Stultz <john.stultz@linaro.org>,
Thomas Gleixner <tglx@linutronix.de>,
Stephen Boyd <sboyd@kernel.org>, Jonathan Corbet <corbet@lwn.net>,
Mark Rutland <Mark.Rutland@arm.com>,
Marc Zyngier <maz@kernel.org>,
Xing Zhengjun <zhengjun.xing@linux.intel.com>,
Chris Mason <clm@fb.com>, LKML <linux-kernel@vger.kernel.org>,
Linux Memory Management List <linux-mm@kvack.org>,
lkp@lists.01.org, lkp@intel.com, ying.huang@intel.com,
zhengjun.xing@intel.com
Subject: Re: [clocksource] 8901ecc231: stress-ng.lockbus.ops_per_sec -9.5% regression
Date: Wed, 4 Aug 2021 21:34:13 -0700 [thread overview]
Message-ID: <a8d99be8-da3f-6c8e-cdbb-efd239ff3f14@linux.intel.com> (raw)
In-Reply-To: <20210805040349.GD4397@paulmck-ThinkPad-P17-Gen-1>
> My current thought is that if more than (say) 100 consecutive attempts
> to read the clocksource get hit with excessive delays, it is time to at
> least do a WARN_ON(), and maybe also time to disable the clocksource
> due to skew. The reason is that if reading the clocksource -always-
> sees excessive delays, perhaps the clock driver or hardware is to blame.
>
> Thoughts?
On TDX this would be fatal because we don't have a usable fallback source
(just jiffies). Better try as hard as possible.
-Andi
>
>
next prev parent reply other threads:[~2021-08-05 4:34 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-21 8:33 [clocksource] 8901ecc231: stress-ng.lockbus.ops_per_sec -9.5% regression kernel test robot
2021-05-21 13:56 ` Paul E. McKenney
2021-05-22 16:08 ` Paul E. McKenney
2021-05-26 6:49 ` Feng Tang
2021-05-26 13:49 ` Paul E. McKenney
2021-05-27 18:29 ` Paul E. McKenney
2021-05-27 19:01 ` Andi Kleen
2021-05-27 19:19 ` Paul E. McKenney
2021-05-27 19:29 ` Matthew Wilcox
2021-05-27 21:05 ` Paul E. McKenney
2021-05-28 0:58 ` Andi Kleen
2021-06-01 17:10 ` Paul E. McKenney
2021-08-02 6:20 ` Chao Gao
2021-08-02 17:02 ` Paul E. McKenney
2021-08-03 8:58 ` Chao Gao
2021-08-03 13:48 ` Paul E. McKenney
2021-08-05 2:16 ` Chao Gao
2021-08-05 4:03 ` Paul E. McKenney
2021-08-05 4:34 ` Andi Kleen [this message]
2021-08-05 15:33 ` Paul E. McKenney
2021-08-05 5:39 ` Chao Gao
2021-08-05 15:37 ` Paul E. McKenney
2021-08-06 2:10 ` Chao Gao
2021-08-06 4:15 ` Paul E. McKenney
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