Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <79b8548e-715a-85ee-aad6-cb0b97753df6@redhat.com>
Date:   Wed, 9 Aug 2023 14:11:09 +1000
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101
 Thunderbird/102.12.0
Subject: Re: [PATCH v8 04/14] KVM: Remove CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
Content-Language: en-US
To:     Raghavendra Rao Ananta <rananta@google.com>,
        Oliver Upton <oliver.upton@linux.dev>,
        Marc Zyngier <maz@kernel.org>,
        James Morse <james.morse@arm.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Huacai Chen <chenhuacai@kernel.org>,
        Zenghui Yu <yuzenghui@huawei.com>,
        Anup Patel <anup@brainfault.org>,
        Atish Patra <atishp@atishpatra.org>,
        Jing Zhang <jingzhangos@google.com>,
        Reiji Watanabe <reijiw@google.com>,
        Colton Lewis <coltonlewis@google.com>,
        David Matlack <dmatlack@google.com>,
        Fuad Tabba <tabba@google.com>,
        linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev,
        linux-mips@vger.kernel.org, kvm-riscv@lists.infradead.org,
        linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org, Shaoqin Huang <shahuang@redhat.com>
References: <20230808231330.3855936-1-rananta@google.com>
 <20230808231330.3855936-5-rananta@google.com>
From:   Gavin Shan <gshan@redhat.com>
In-Reply-To: <20230808231330.3855936-5-rananta@google.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Precedence: bulk


On 8/9/23 09:13, Raghavendra Rao Ananta wrote:
> kvm_arch_flush_remote_tlbs() or CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
> are two mechanisms to solve the same problem, allowing
> architecture-specific code to provide a non-IPI implementation of
> remote TLB flushing.
> 
> Dropping CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL allows KVM to standardize
> all architectures on kvm_arch_flush_remote_tlbs() instead of
> maintaining two mechanisms.
> 
> Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
> Reviewed-by: Shaoqin Huang <shahuang@redhat.com>
> ---
>   virt/kvm/Kconfig    | 3 ---
>   virt/kvm/kvm_main.c | 2 --
>   2 files changed, 5 deletions(-)
> 

Reviewed-by: Gavin Shan <gshan@redhat.com>

> diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig
> index b74916de5183a..484d0873061ca 100644
> --- a/virt/kvm/Kconfig
> +++ b/virt/kvm/Kconfig
> @@ -62,9 +62,6 @@ config HAVE_KVM_CPU_RELAX_INTERCEPT
>   config KVM_VFIO
>          bool
>   
> -config HAVE_KVM_ARCH_TLB_FLUSH_ALL
> -       bool
> -
>   config HAVE_KVM_INVALID_WAKEUPS
>          bool
>   
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index 70e5479797ac3..d6b0507861550 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -345,7 +345,6 @@ bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
>   }
>   EXPORT_SYMBOL_GPL(kvm_make_all_cpus_request);
>   
> -#ifndef CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
>   void kvm_flush_remote_tlbs(struct kvm *kvm)
>   {
>   	++kvm->stat.generic.remote_tlb_flush_requests;
> @@ -366,7 +365,6 @@ void kvm_flush_remote_tlbs(struct kvm *kvm)
>   		++kvm->stat.generic.remote_tlb_flush;
>   }
>   EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs);
> -#endif
>   
>   static void kvm_flush_shadow_all(struct kvm *kvm)
>   {