KVM: x86: hyper-v: Allocate 'struct kvm_vcpu_hv' dynamically
Hyper-V context is only needed for guests which use Hyper-V emulation in
KVM (e.g. Windows/Hyper-V guests). 'struct kvm_vcpu_hv' is, however, quite
big, it accounts for more than 1/4 of the total 'struct kvm_vcpu_arch'
which is also quite big already. This all looks like a waste.
Allocate 'struct kvm_vcpu_hv' dynamically. This patch does not bring any
(intentional) functional change as we still allocate the context
unconditionally but it paves the way to doing that only when needed.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210126134816.1880136-13-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index b6de568..95eb6e9 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -519,6 +519,7 @@ struct kvm_vcpu_hv_synic {
/* Hyper-V per vcpu emulation context */
struct kvm_vcpu_hv {
+ struct kvm_vcpu *vcpu;
u32 vp_index;
u64 hv_vapic;
s64 runtime_offset;
@@ -735,7 +736,7 @@ struct kvm_vcpu_arch {
/* used for guest single stepping over the given code position */
unsigned long singlestep_rip;
- struct kvm_vcpu_hv hyperv;
+ struct kvm_vcpu_hv *hyperv;
struct kvm_vcpu_xen xen;
cpumask_var_t wbinvd_dirty_mask;