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Message-ID: <7de112b2-e6d1-1f9d-a040-1c4cfee40b22@gmail.com>
Date:   Wed, 9 Feb 2022 17:00:16 +0800
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Subject: Re: [PATCH v2 2/6] KVM: x86/pmu: Refactoring find_arch_event() to
 pmc_perf_hw_id()
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To:     Jim Mattson <jmattson@google.com>
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Joerg Roedel <joro@8bytes.org>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Like Xu <likexu@tencent.com>
References: <20211130074221.93635-1-likexu@tencent.com>
 <20211130074221.93635-3-likexu@tencent.com>
 <CALMp9eQG7eqq+u3igApsRDV=tt0LdjZzmD_dC8zw=gt=f5NjSA@mail.gmail.com>
From:   Like Xu <like.xu.linux@gmail.com>
Organization: Tencent
In-Reply-To: <CALMp9eQG7eqq+u3igApsRDV=tt0LdjZzmD_dC8zw=gt=f5NjSA@mail.gmail.com>
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On 5/2/2022 9:55 am, Jim Mattson wrote:
>> +static unsigned int amd_pmc_perf_hw_id(struct kvm_pmc *pmc)
>>   {
>> +       u8 event_select = pmc->eventsel & ARCH_PERFMON_EVENTSEL_EVENT;
> On AMD, the event select is 12 bits.

Out of your carefulness, we already know this fact.

This function to get the perf_hw_id by the last 16 bits still works because we 
currently
do not have a 12-bits-select event defined in the amd_event_mapping[]. The 
12-bits-select
events (if any) will be programed in the type of PERF_TYPE_RAW.

IMO, a minor patch that renames some AMD variables and updates the relevant comments
to avoid misunderstandings is quite acceptable.

Thanks,
Like Xu