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Subject: Re: [PATCH v4 4/5] KVM: LAPIC: Delay trace advance expire delta
To:     Wanpeng Li <kernellwp@gmail.com>
Cc:     LKML <linux-kernel@vger.kernel.org>, kvm <kvm@vger.kernel.org>,
        =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        Liran Alon <liran.alon@oracle.com>
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From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <bd60e5c2-e3c5-80fc-3a1d-c75809573945@redhat.com>
Date:   Mon, 20 May 2019 13:33:28 +0200
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On 20/05/19 13:22, Wanpeng Li wrote:
>>
>> We would like to move wait_lapic_expire() just before vmentry, which would
>> place wait_lapic_expire() again inside the extended quiescent state.  Drop
>> the tracepoint, but add instead another one that can be useful and where
>> we can check the status of the adaptive tuning procedure.
> https://lkml.org/lkml/2019/5/15/1435
> 
> Maybe Sean's comment is reasonable, per-vCPU debugfs entry for
> adaptive tuning and wait_lapic_expire() tracepoint for hand tuning.

Hmm, yeah, that makes sense.  The location of the tracepoint is a bit
weird, but I guess we can add a comment in the code.

Paolo