From: Vitaly Kuznetsov <vkuzn...@redhat.com>
Add support for Hyper-V TLB flush which recently got added to KVM.
Just like regular Hyper-V we announce HV_EX_PROCESSOR_MASKS_RECOMMENDED
regardless of how many vCPUs we have. Windows is 'smart' and uses less
expensive non-EX Hypercall whenever possible (when it wants to flush TLB
for all vCPUs or the maximum vCPU index in the vCPU set requires flushing
is less than 64).
Signed-off-by: Vitaly Kuznetsov <vkuzn...@redhat.com>
Message-Id: <20180610184927.19309-1-vkuzn...@redhat.com>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
target/i386/cpu.c | 1 +
target/i386/cpu.h | 1 +
target/i386/hyperv-proto.h | 1 +
target/i386/kvm.c | 15 ++++++++++++++-
4 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 1e6a7d0..d57f310 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -5415,6 +5415,7 @@ static Property x86_cpu_properties[] = {
DEFINE_PROP_BOOL("hv-stimer", X86CPU, hyperv_stimer, false),
DEFINE_PROP_BOOL("hv-frequencies", X86CPU, hyperv_frequencies, false),
DEFINE_PROP_BOOL("hv-reenlightenment", X86CPU, hyperv_reenlightenment,
false),
+ DEFINE_PROP_BOOL("hv-tlbflush", X86CPU, hyperv_tlbflush, false),
DEFINE_PROP_BOOL("check", X86CPU, check_cpuid, true),
DEFINE_PROP_BOOL("enforce", X86CPU, enforce_cpuid, false),
DEFINE_PROP_BOOL("kvm", X86CPU, expose_kvm, true),
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 8eaefee..8b1ddfe 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -1367,6 +1367,7 @@ struct X86CPU {
bool hyperv_stimer;
bool hyperv_frequencies;
bool hyperv_reenlightenment;
+ bool hyperv_tlbflush;
bool check_cpuid;
bool enforce_cpuid;
bool expose_kvm;
diff --git a/target/i386/hyperv-proto.h b/target/i386/hyperv-proto.h
index 93352eb..d6d5a79 100644
--- a/target/i386/hyperv-proto.h
+++ b/target/i386/hyperv-proto.h
@@ -58,6 +58,7 @@
#define HV_APIC_ACCESS_RECOMMENDED (1u << 3)
#define HV_SYSTEM_RESET_RECOMMENDED (1u << 4)
#define HV_RELAXED_TIMING_RECOMMENDED (1u << 5)
+#define HV_EX_PROCESSOR_MASKS_RECOMMENDED (1u << 11)
/*
* Basic virtualized MSRs
diff --git a/target/i386/kvm.c b/target/i386/kvm.c
index 032f0ad..ebb2d23 100644
--- a/target/i386/kvm.c
+++ b/target/i386/kvm.c
@@ -601,7 +601,8 @@ static bool hyperv_enabled(X86CPU *cpu)
cpu->hyperv_runtime ||
cpu->hyperv_synic ||
cpu->hyperv_stimer ||
- cpu->hyperv_reenlightenment);
+ cpu->hyperv_reenlightenment ||
+ cpu->hyperv_tlbflush);
}
static int kvm_arch_set_tsc_khz(CPUState *cs)
@@ -839,6 +840,18 @@ int kvm_arch_init_vcpu(CPUState *cs)
if (cpu->hyperv_vapic) {
c->eax |= HV_APIC_ACCESS_RECOMMENDED;
}
+ if (cpu->hyperv_tlbflush) {
+ if (kvm_check_extension(cs->kvm_state,
+ KVM_CAP_HYPERV_TLBFLUSH) <= 0) {
+ fprintf(stderr, "Hyper-V TLB flush support "
+ "(requested by 'hv-tlbflush' cpu flag) "
+ " is not supported by kernel\n");
+ return -ENOSYS;
+ }
+ c->eax |= HV_REMOTE_TLB_FLUSH_RECOMMENDED;
+ c->eax |= HV_EX_PROCESSOR_MASKS_RECOMMENDED;
+ }
+
c->ebx = cpu->hyperv_spinlock_attempts;
c = &cpuid_data.entries[cpuid_i++];
--
1.8.3.1
