Re: [PATCH RESEND] nohz: Restart tick before do softirq

From: Frederic Weisbecker
Date: Wed Feb 03 2021 - 08:12:36 EST


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.