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([2001:b07:add:ec09:c399:bc87:7b6c:fb2a]) by smtp.gmail.com with ESMTPSA id 25sm9762200wmk.20.2021.06.10.09.17.35 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 10 Jun 2021 09:17:36 -0700 (PDT) Subject: Re: [PATCH v3 2/8] KVM: Integrate gfn_to_memslot_approx() into search_memslots() To: Sean Christopherson , "Maciej S. Szmigiero" Cc: Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Igor Mammedov , Marc Zyngier , James Morse , Julien Thierry , Suzuki K Poulose , Huacai Chen , Aleksandar Markovic , Paul Mackerras , Christian Borntraeger , Janosch Frank , David Hildenbrand , Cornelia Huck , Claudio Imbrenda , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org References: From: Paolo Bonzini Message-ID: Date: Thu, 10 Jun 2021 18:17:33 +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: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 19/05/21 23:24, Sean Christopherson wrote: > An alternative to modifying the PPC code would be to make the existing > search_memslots() a wrapper to __search_memslots(), with the latter taking > @approx. Let's just modify PPC to use __gfn_to_memslot instead of search_memslots(). __gfn_to_memslot() has never introduced any functionality over search_memslots(), ever since search_memslots() was introduced in 2011. Paolo > We might also want to make this __always_inline to improve the likelihood of the > compiler optimizing away @approx. I doubt it matters in practice... >