[PATCH v9 02/40] KVM: x86: hyper-v: Resurrect dedicated KVM_REQ_HV_TLB_FLUSH flag

Vitaly Kuznetsov
2022-08-03T13:41:28Z

In preparation to implementing fine-grained Hyper-V TLB flush and
L2 TLB flush, resurrect dedicated KVM_REQ_HV_TLB_FLUSH request bit. As
KVM_REQ_TLB_FLUSH_GUEST/KVM_REQ_TLB_FLUSH_CURRENT are stronger operations,
clear KVM_REQ_HV_TLB_FLUSH request in kvm_service_local_tlb_flush_requests()
when any of these were also requested.

No (real) functional change intended.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
arch/x86/include/asm/kvm_host.h | 2 ++
arch/x86/kvm/hyperv.c | 4 ++--
arch/x86/kvm/x86.c | 10 ++++++++--
3 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 503262dd6a85..c851db4344a9 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -108,6 +108,8 @@
KVM_ARCH_REQ_FLAGS(30, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)
#define KVM_REQ_MMU_FREE_OBSOLETE_ROOTS \
KVM_ARCH_REQ_FLAGS(31, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)
+#define KVM_REQ_HV_TLB_FLUSH \
+ KVM_ARCH_REQ_FLAGS(32, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)

#define CR0_RESERVED_BITS \
(~(unsigned long)(X86_CR0_PE | X86_CR0_MP | X86_CR0_EM | X86_CR0_TS \
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index ed804447589c..ff69352d1387 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1876,11 +1876,11 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc)
* analyze it here, flush TLB regardless of the specified address space.
*/
if (all_cpus) {
- kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH_GUEST);
+ kvm_make_all_cpus_request(kvm, KVM_REQ_HV_TLB_FLUSH);
} else {
sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask);

- kvm_make_vcpus_request_mask(kvm, KVM_REQ_TLB_FLUSH_GUEST, vcpu_mask);
+ kvm_make_vcpus_request_mask(kvm, KVM_REQ_HV_TLB_FLUSH, vcpu_mask);
}

ret_success:
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 55b37dba6c54..eea435013bd0 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3401,11 +3401,17 @@ static inline void kvm_vcpu_flush_tlb_current(struct kvm_vcpu *vcpu)
*/
void kvm_service_local_tlb_flush_requests(struct kvm_vcpu *vcpu)
{
- if (kvm_check_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu))
+ if (kvm_check_request(KVM_REQ_TLB_FLUSH_CURRENT, vcpu)) {
kvm_vcpu_flush_tlb_current(vcpu);
+ kvm_clear_request(KVM_REQ_HV_TLB_FLUSH, vcpu);
+ }

- if (kvm_check_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu))
+ if (kvm_check_request(KVM_REQ_TLB_FLUSH_GUEST, vcpu)) {
+ kvm_vcpu_flush_tlb_guest(vcpu);
+ kvm_clear_request(KVM_REQ_HV_TLB_FLUSH, vcpu);
+ } else if (kvm_check_request(KVM_REQ_HV_TLB_FLUSH, vcpu)) {
kvm_vcpu_flush_tlb_guest(vcpu);
+ }
}
EXPORT_SYMBOL_GPL(kvm_service_local_tlb_flush_requests);

--
2.35.3