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Date:   Wed, 3 Feb 2021 14:11:05 +0100
From:   Frederic Weisbecker <frederic@kernel.org>
To:     chenshiyan <chenshiyan@linux.alibaba.com>
Cc:     fweisbec@gmail.com, tglx@linutronix.de, mingo@kernel.org,
        torvalds@linux-foundation.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH RESEND] nohz: Restart tick before do softirq
Message-ID: <20210203131105.GA3666@lothringen>
References: <1612151143-72242-1-git-send-email-chenshiyan@linux.alibaba.com>
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On Wed, Feb 03, 2021 at 09:04:05PM +0800, chenshiyan wrote:
> Are you working on an architecture that doesn't implement it?
> -No, we test it on x86.
> 
> The problem is , when it's doing softirq, but there’s no tick, so we don’t know how long 
> It takes. The TOP or some other procs can not show the right value of sirq.

But IRQTIME counting is based on sched_clock() which shouldn't use jiffies
in the case in x86. In fact jiffies based sched_clock() isn't suitable for
IRQTIME at all. So I don't understand the problem.