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: <c33b0518-6e64-7acf-efa8-f404fce1ccac@redhat.com>
Date:   Wed, 9 Aug 2023 14:00:15 +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 02/14] KVM: Declare kvm_arch_flush_remote_tlbs()
 globally
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
References: <20230808231330.3855936-1-rananta@google.com>
 <20230808231330.3855936-3-rananta@google.com>
From:   Gavin Shan <gshan@redhat.com>
In-Reply-To: <20230808231330.3855936-3-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:
> There's no reason for the architectures to declare
> kvm_arch_flush_remote_tlbs() in their own headers. Hence to
> avoid this duplication, make the declaration global, leaving
> the architectures to define only __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS
> as needed.
> 
> Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
> ---
>   arch/mips/include/asm/kvm_host.h | 1 -
>   include/linux/kvm_host.h         | 2 ++
>   2 files changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
> index 9b0ad8f3bf327..54a85f1d4f2c8 100644
> --- a/arch/mips/include/asm/kvm_host.h
> +++ b/arch/mips/include/asm/kvm_host.h
> @@ -897,6 +897,5 @@ static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {}
>   static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {}
>   
>   #define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS
> -int kvm_arch_flush_remote_tlbs(struct kvm *kvm);
>   
>   #endif /* __MIPS_KVM_HOST_H__ */
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index e3f968b38ae97..ade5d4500c2ce 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -1484,6 +1484,8 @@ static inline int kvm_arch_flush_remote_tlbs(struct kvm *kvm)
>   {
>   	return -ENOTSUPP;
>   }
> +#else
> +int kvm_arch_flush_remote_tlbs(struct kvm *kvm);
>   #endif
>   
>   #ifdef __KVM_HAVE_ARCH_NONCOHERENT_DMA

Is the declaration inconsistent to that in arch/x86/include/asm/kvm_host.h?
In order to keep them consistent, I guess we need move kvm_arch_flush_remote_tlbs()
from x86's header file to arch/x86/kvm/mmu/mmu.c and 'inline' needs to be dropped.

Thanks,
Gavin