[PATCH v10 02/39] KVM: x86: hyper-v: Resurrect dedicated KVM_REQ_HV_TLB_FLUSH flag

From: Vitaly Kuznetsov <vkuznets@redhat.com>
To: kvm@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>,
	Wanpeng Li <wanpengli@tencent.com>,
	Jim Mattson <jmattson@google.com>,
	Michael Kelley <mikelley@microsoft.com>,
	Siddharth Chandrasekaran <sidcha@amazon.de>,
	Yuan Yao <yuan.yao@linux.intel.com>,
	Maxim Levitsky <mlevitsk@redhat.com>,
	linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v10 02/39] KVM: x86: hyper-v: Resurrect dedicated KVM_REQ_HV_TLB_FLUSH flag
Date: Wed, 21 Sep 2022 17:23:59 +0200	[thread overview]
Message-ID: <20220921152436.3673454-3-vkuznets@redhat.com> (raw)
In-Reply-To: <20220921152436.3673454-1-vkuznets@redhat.com>

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 504daf473092..45c390c804f0 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 0adf4a437e85..3c0f639f6a05 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1870,11 +1870,11 @@ 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 f62d5799fcd7..86504a8bfd9a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3418,11 +3418,17 @@ 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);
 
-- 
2.37.3

