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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
Date: Wed, 3 Feb 2021 14:11:05 +0100	[thread overview]
Message-ID: <20210203131105.GA3666@lothringen> (raw)
In-Reply-To: <B2A33260-1D22-4C29-9811-64F0A68F0D64@linux.alibaba.com>

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.

      reply	other threads:[~2021-02-03 13:12 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-02-01  3:45 [PATCH RESEND] nohz: Restart tick before do softirq chenshiyan
2021-02-01 12:38 ` Frederic Weisbecker
2021-02-03 13:04   ` chenshiyan
2021-02-03 13:11     ` Frederic Weisbecker [this message]

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