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Date:   Wed, 23 Oct 2019 10:29:12 +0200 (CEST)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Wanpeng Li <kernellwp@gmail.com>
cc:     LKML <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>, kvm <kvm@vger.kernel.org>,
        Frederic Weisbecker <frederic@kernel.org>
Subject: Re: [PATCH v2] sched/nohz: Optimize get_nohz_timer_target()
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On Wed, 23 Oct 2019, Wanpeng Li wrote:
> I didn't see your refactor to get_nohz_timer_target() which you
> mentioned in IRC after four months, I can observe cyclictest drop from
> 4~5us to 8us in kvm guest(we offload the lapic timer emulation to
> housekeeping cpu to avoid timer fire external interrupt on the pCPU
> which vCPU resident incur a vCPU vmexit) w/o this patch in the case of
> there is no busy housekeeping cpu. The score can be recovered after I
> give stress to create a busy housekeeping cpu.
> 
> Could you consider applying this patch for temporary since I'm not
> sure when the refactor can be ready.

Yeah. It's delayed (again).... Will pick that up.

Thanks,

	tglx