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From: tglx@linutronix.de (Thomas Gleixner)
To: linux-arm-kernel@lists.infradead.org
Subject: Problem about CPU stalling in hrtimer_intterrupts()
Date: Sat, 24 Oct 2015 18:58:18 +0900 (KST)	[thread overview]
Message-ID: <alpine.DEB.2.11.1510241854410.4639@nanos> (raw)
In-Reply-To: <5628E7E9.409@huawei.com>

On Thu, 22 Oct 2015, Yang Yingliang wrote:

> But I found out when the cpu is stalling, basenow.tv64(7676664221321) is
> bigger than ktime_get().tv64(7336008904750) in hrtimer_interrupt() and
> the timer->_softexpires is 7336288000000. This makes it can not finish
> the while loop until ktime_get().tv64 arrives basenow.tv64.
> 
> Is it correct that basenow bigger than ktime_get() ?

You only can compare basenow and ktime_get() for the clock monotonic
base. If you are actually observing this on clock monotonic base then
base->offset of clock monotonic is not 0, which should never happen.

Thanks,

	tglx

      reply	other threads:[~2015-10-24  9:58 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-10-22  6:43 Problem about CPU stalling in hrtimer_intterrupts() Yang Yingliang
2015-10-22  7:43 ` Thomas Gleixner
2015-10-22  9:28   ` Ding Tianhong
2015-10-22 10:25     ` Thomas Gleixner
2015-10-22 13:43       ` Yang Yingliang
2015-10-24  9:58         ` Thomas Gleixner [this message]

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