| Message ID | 20230715005405.3689586-3-rananta@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: arm64: Add support for FEAT_TLBIRANGE | expand |
Hi Raghavendra, David, On 15/7/23 02:53, Raghavendra Rao Ananta wrote: > From: David Matlack <dmatlack@google.com> > > Use kvm_arch_flush_remote_tlbs() instead of > CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL. The two mechanisms 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. > > Opt to standardize on kvm_arch_flush_remote_tlbs() since it avoids > duplicating the generic TLB stats across architectures that implement > their own remote TLB flush. > > This adds an extra function call to the ARM64 kvm_flush_remote_tlbs() > path, but that is a small cost in comparison to flushing remote TLBs. > > In addition, instead of just incrementing remote_tlb_flush_requests > stat, the generic interface would also increment the > remote_tlb_flush stat. > > Signed-off-by: David Matlack <dmatlack@google.com> > Signed-off-by: Raghavendra Rao Ananta <rananta@google.com> > Reviewed-by: Zenghui Yu <zenghui.yu@linux.dev> > Acked-by: Oliver Upton <oliver.upton@linux.dev> > Reviewed-by: Gavin Shan <gshan@redhat.com> > --- > arch/arm64/include/asm/kvm_host.h | 3 +++ > arch/arm64/kvm/Kconfig | 1 - > arch/arm64/kvm/mmu.c | 6 +++--- > virt/kvm/Kconfig | 3 --- > virt/kvm/kvm_main.c | 2 -- > 5 files changed, 6 insertions(+), 9 deletions(-) You are doing 2 changes in the same patch: - Have ARM use kvm_arch_flush_remote_tlbs() instead of HAVE_KVM_ARCH_TLB_FLUSH_ALL, - Drop the now unused HAVE_KVM_ARCH_TLB_FLUSH_ALL. Commits should be atomic, to allow partial revert or cherry-pick. Preferably splitting this patch in 2: Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Regards, Phil.
On 7/15/23 08:53, Raghavendra Rao Ananta wrote: > From: David Matlack <dmatlack@google.com> > > Use kvm_arch_flush_remote_tlbs() instead of > CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL. The two mechanisms 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. > > Opt to standardize on kvm_arch_flush_remote_tlbs() since it avoids > duplicating the generic TLB stats across architectures that implement > their own remote TLB flush. > > This adds an extra function call to the ARM64 kvm_flush_remote_tlbs() > path, but that is a small cost in comparison to flushing remote TLBs. > > In addition, instead of just incrementing remote_tlb_flush_requests > stat, the generic interface would also increment the > remote_tlb_flush stat. > > Signed-off-by: David Matlack <dmatlack@google.com> > Signed-off-by: Raghavendra Rao Ananta <rananta@google.com> > Reviewed-by: Zenghui Yu <zenghui.yu@linux.dev> > Acked-by: Oliver Upton <oliver.upton@linux.dev> > Reviewed-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Shaoqin Huang <shahuang@redhat.com> > --- > arch/arm64/include/asm/kvm_host.h | 3 +++ > arch/arm64/kvm/Kconfig | 1 - > arch/arm64/kvm/mmu.c | 6 +++--- > virt/kvm/Kconfig | 3 --- > virt/kvm/kvm_main.c | 2 -- > 5 files changed, 6 insertions(+), 9 deletions(-) > > diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h > index 8b6096753740..7281222f24ef 100644 > --- a/arch/arm64/include/asm/kvm_host.h > +++ b/arch/arm64/include/asm/kvm_host.h > @@ -1111,6 +1111,9 @@ int __init kvm_set_ipa_limit(void); > #define __KVM_HAVE_ARCH_VM_ALLOC > struct kvm *kvm_arch_alloc_vm(void); > > +#define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS > +int kvm_arch_flush_remote_tlbs(struct kvm *kvm); > + > static inline bool kvm_vm_is_protected(struct kvm *kvm) > { > return false; > diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig > index f531da6b362e..6b730fcfee37 100644 > --- a/arch/arm64/kvm/Kconfig > +++ b/arch/arm64/kvm/Kconfig > @@ -25,7 +25,6 @@ menuconfig KVM > select MMU_NOTIFIER > select PREEMPT_NOTIFIERS > select HAVE_KVM_CPU_RELAX_INTERCEPT > - select HAVE_KVM_ARCH_TLB_FLUSH_ALL > select KVM_MMIO > select KVM_GENERIC_DIRTYLOG_READ_PROTECT > select KVM_XFER_TO_GUEST_WORK > diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c > index 6db9ef288ec3..0ac721fa27f1 100644 > --- a/arch/arm64/kvm/mmu.c > +++ b/arch/arm64/kvm/mmu.c > @@ -161,15 +161,15 @@ static bool memslot_is_logging(struct kvm_memory_slot *memslot) > } > > /** > - * kvm_flush_remote_tlbs() - flush all VM TLB entries for v7/8 > + * kvm_arch_flush_remote_tlbs() - flush all VM TLB entries for v7/8 > * @kvm: pointer to kvm structure. > * > * Interface to HYP function to flush all VM TLB entries > */ > -void kvm_flush_remote_tlbs(struct kvm *kvm) > +int kvm_arch_flush_remote_tlbs(struct kvm *kvm) > { > - ++kvm->stat.generic.remote_tlb_flush_requests; > kvm_call_hyp(__kvm_tlb_flush_vmid, &kvm->arch.mmu); > + return 0; > } > > static bool kvm_is_device_pfn(unsigned long pfn) > diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig > index b74916de5183..484d0873061c 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 70e5479797ac..d6b050786155 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) > {
Hi Philippe, On Mon, Jul 17, 2023 at 1:13 AM Philippe Mathieu-Daudé <philmd@linaro.org> wrote: > > Hi Raghavendra, David, > > On 15/7/23 02:53, Raghavendra Rao Ananta wrote: > > From: David Matlack <dmatlack@google.com> > > > > Use kvm_arch_flush_remote_tlbs() instead of > > CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL. The two mechanisms 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. > > > > Opt to standardize on kvm_arch_flush_remote_tlbs() since it avoids > > duplicating the generic TLB stats across architectures that implement > > their own remote TLB flush. > > > > This adds an extra function call to the ARM64 kvm_flush_remote_tlbs() > > path, but that is a small cost in comparison to flushing remote TLBs. > > > > In addition, instead of just incrementing remote_tlb_flush_requests > > stat, the generic interface would also increment the > > remote_tlb_flush stat. > > > > Signed-off-by: David Matlack <dmatlack@google.com> > > Signed-off-by: Raghavendra Rao Ananta <rananta@google.com> > > Reviewed-by: Zenghui Yu <zenghui.yu@linux.dev> > > Acked-by: Oliver Upton <oliver.upton@linux.dev> > > Reviewed-by: Gavin Shan <gshan@redhat.com> > > --- > > arch/arm64/include/asm/kvm_host.h | 3 +++ > > arch/arm64/kvm/Kconfig | 1 - > > arch/arm64/kvm/mmu.c | 6 +++--- > > virt/kvm/Kconfig | 3 --- > > virt/kvm/kvm_main.c | 2 -- > > 5 files changed, 6 insertions(+), 9 deletions(-) > > You are doing 2 changes in the same patch: > > - Have ARM use kvm_arch_flush_remote_tlbs() instead of > HAVE_KVM_ARCH_TLB_FLUSH_ALL, > - Drop the now unused HAVE_KVM_ARCH_TLB_FLUSH_ALL. > > Commits should be atomic, to allow partial > revert or cherry-pick. > > Preferably splitting this patch in 2: > Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> > Thanks for the suggestion. I guess that makes sense. I'll split the patch in two for v7. - Raghavendra > Regards, > > Phil. >
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 8b6096753740..7281222f24ef 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -1111,6 +1111,9 @@ int __init kvm_set_ipa_limit(void); #define __KVM_HAVE_ARCH_VM_ALLOC struct kvm *kvm_arch_alloc_vm(void); +#define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS +int kvm_arch_flush_remote_tlbs(struct kvm *kvm); + static inline bool kvm_vm_is_protected(struct kvm *kvm) { return false; diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig index f531da6b362e..6b730fcfee37 100644 --- a/arch/arm64/kvm/Kconfig +++ b/arch/arm64/kvm/Kconfig @@ -25,7 +25,6 @@ menuconfig KVM select MMU_NOTIFIER select PREEMPT_NOTIFIERS select HAVE_KVM_CPU_RELAX_INTERCEPT - select HAVE_KVM_ARCH_TLB_FLUSH_ALL select KVM_MMIO select KVM_GENERIC_DIRTYLOG_READ_PROTECT select KVM_XFER_TO_GUEST_WORK diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 6db9ef288ec3..0ac721fa27f1 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -161,15 +161,15 @@ static bool memslot_is_logging(struct kvm_memory_slot *memslot) } /** - * kvm_flush_remote_tlbs() - flush all VM TLB entries for v7/8 + * kvm_arch_flush_remote_tlbs() - flush all VM TLB entries for v7/8 * @kvm: pointer to kvm structure. * * Interface to HYP function to flush all VM TLB entries */ -void kvm_flush_remote_tlbs(struct kvm *kvm) +int kvm_arch_flush_remote_tlbs(struct kvm *kvm) { - ++kvm->stat.generic.remote_tlb_flush_requests; kvm_call_hyp(__kvm_tlb_flush_vmid, &kvm->arch.mmu); + return 0; } static bool kvm_is_device_pfn(unsigned long pfn) diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig index b74916de5183..484d0873061c 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 70e5479797ac..d6b050786155 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) {