On Fri, Apr 18, 2025, Paolo Bonzini wrote:
> kvm_arch_has_irq_bypass() is a small function and even though it does
> not appear in any *really* hot paths, it's also not entirely rare.
> Make it inline---it also works out nicely in preparation for using it in
> kvm-intel.ko and kvm-amd.ko, since the function is not currently exported.
>
> Suggested-by: Linus Torvalds <torva...@linux-foundation.org>
> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
> ---
> arch/arm64/include/asm/kvm_host.h | 5 +++++
> arch/arm64/kvm/arm.c | 5 -----
> arch/powerpc/include/asm/kvm_host.h | 2 ++
> arch/x86/include/asm/kvm_host.h | 6 ++++++
> arch/x86/kvm/x86.c | 5 -----
> include/linux/kvm_host.h | 1 -
> 6 files changed, 13 insertions(+), 11 deletions(-)
...
> diff --git a/arch/powerpc/include/asm/kvm_host.h
> b/arch/powerpc/include/asm/kvm_host.h
> index 2d139c807577..6f761b77b813 100644
> --- a/arch/powerpc/include/asm/kvm_host.h
> +++ b/arch/powerpc/include/asm/kvm_host.h
> @@ -907,4 +907,6 @@ static inline void kvm_arch_flush_shadow_all(struct kvm
> *kvm) {}
> static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {}
> static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {}
>
> +bool kvm_arch_has_irq_bypass(void);
...
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index 291d49b9bf05..82f044e4b3f5 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -2383,7 +2383,6 @@ struct kvm_vcpu *kvm_get_running_vcpu(void);
> struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void);
>
> #if IS_ENABLED(CONFIG_HAVE_KVM_IRQ_BYPASS)
> -bool kvm_arch_has_irq_bypass(void);
Moving the declaration to PPC is unnecessary, and IMO undesirable. It's
perfectly
legal to have a non-static declaration follow a "static inline", and
asm/kvm_host.h
is included by linux/kvm_host.h, i.e. the per-arch "static inline" is guaranteed
to be processed first.
And KVM already have multiple instances of this, e.g. kvm_arch_vcpu_blocking().
If only for consistency, I vote to keep the common declaration.
> int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *,
> struct irq_bypass_producer *);
> void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *,
> --
> 2.43.5
>
