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([2001:b07:6468:f312:c8dd:75d4:99ab:290a]) by smtp.gmail.com with ESMTPSA id e18sm3537900ejh.64.2021.06.17.04.19.51 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 17 Jun 2021 04:19:52 -0700 (PDT) Subject: Re: [PATCH v10 3/5] KVM: stats: Add documentation for binary statistics interface To: Greg KH , Jing Zhang References: <20210617044146.2667540-1-jingzhangos@google.com> <20210617044146.2667540-4-jingzhangos@google.com> From: Paolo Bonzini Message-ID: Date: Thu, 17 Jun 2021 13:19:50 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=pbonzini@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Cc: KVM , David Hildenbrand , Paul Mackerras , Linuxkselftest , Claudio Imbrenda , Will Deacon , KVMARM , Emanuele Giuseppe Esposito , LinuxS390 , Janosch Frank , Marc Zyngier , Huacai Chen , Christian Borntraeger , Aleksandar Markovic , David Rientjes , KVMPPC , Krish Sadhukhan , David Matlack , Jim Mattson , Thomas Bogendoerfer , Sean Christopherson , Cornelia Huck , Peter Shier , LinuxMIPS , Vitaly Kuznetsov X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu On 17/06/21 08:07, Greg KH wrote: >> The statistics data itself could be read out by userspace telemetry >> periodically without any extra parsing or setup effort. > Do you have a pointer to userspace code that can do such a thing that > others can use? We do not like adding apis to the kernel without at > least seeing the user of those apis, especially for complex things like > this. > > Ideally you would include some library code in the kernel tree itself > that everyone can use for this for their own programs. You have > provided a test which is great, but how do we know it works for "real" > usages? I am pretty sure that Google is using this internally, but we are also going to work on QEMU and Libvirt support for this. As for the rest, thanks for the review---I'll let Jing act on it and only add my own remarks in a couple places. Paolo _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm