From: Uros Bizjak <ubizjak@xxxxxxxxx>
Replace inline assembly in nested_vmx_check_vmentry_hw
with a call to __vmx_vcpu_run. The function is not
performance critical, so (double) GPR save/restore
in __vmx_vcpu_run can be tolerated, as far as performance
effects are concerned.
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Sean Christopherson <seanjc@xxxxxxxxxx>
Reviewed-and-tested-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Signed-off-by: Uros Bizjak <ubizjak@xxxxxxxxx>
[sean: dropped versioning info from changelog]
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/vmx/nested.c | 32 +++-----------------------------
arch/x86/kvm/vmx/vmenter.S | 2 +-
arch/x86/kvm/vmx/vmx.c | 2 --
arch/x86/kvm/vmx/vmx.h | 1 +
4 files changed, 5 insertions(+), 32 deletions(-)
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index e2f26564a12d..5bbb4d667370 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -12,6 +12,7 @@
#include "nested.h"
#include "pmu.h"
#include "trace.h"
+#include "vmx.h"
#include "x86.h"
static bool __read_mostly enable_shadow_vmcs = 1;
@@ -3057,35 +3058,8 @@ static int nested_vmx_check_vmentry_hw(struct kvm_vcpu *vcpu)
vmx->loaded_vmcs->host_state.cr4 = cr4;
}
- asm(
- "sub $%c[wordsize], %%" _ASM_SP "\n\t" /* temporarily adjust RSP for CALL */
- "cmp %%" _ASM_SP ", %c[host_state_rsp](%[loaded_vmcs]) \n\t"
- "je 1f \n\t"
- __ex("vmwrite %%" _ASM_SP ", %[HOST_RSP]") "\n\t"
- "mov %%" _ASM_SP ", %c[host_state_rsp](%[loaded_vmcs]) \n\t"
- "1: \n\t"
- "add $%c[wordsize], %%" _ASM_SP "\n\t" /* un-adjust RSP */
-
- /* Check if vmlaunch or vmresume is needed */
- "cmpb $0, %c[launched](%[loaded_vmcs])\n\t"
-
- /*
- * VMLAUNCH and VMRESUME clear RFLAGS.{CF,ZF} on VM-Exit, set
- * RFLAGS.CF on VM-Fail Invalid and set RFLAGS.ZF on VM-Fail
- * Valid. vmx_vmenter() directly "returns" RFLAGS, and so the
- * results of VM-Enter is captured via CC_{SET,OUT} to vm_fail.
- */
- "call vmx_vmenter\n\t"
-
- CC_SET(be)
- : ASM_CALL_CONSTRAINT, CC_OUT(be) (vm_fail)
- : [HOST_RSP]"r"((unsigned long)HOST_RSP),
- [loaded_vmcs]"r"(vmx->loaded_vmcs),
- [launched]"i"(offsetof(struct loaded_vmcs, launched)),
- [host_state_rsp]"i"(offsetof(struct loaded_vmcs, host_state.rsp)),
- [wordsize]"i"(sizeof(ulong))
- : "memory"
- );
+ vm_fail = __vmx_vcpu_run(vmx, (unsigned long *)&vcpu->arch.regs,
+ vmx->loaded_vmcs->launched);
if (vmx->msr_autoload.host.nr)
vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, vmx->msr_autoload.host.nr);
diff --git a/arch/x86/kvm/vmx/vmenter.S b/arch/x86/kvm/vmx/vmenter.S
index e85aa5faa22d..3a6461694fc2 100644
--- a/arch/x86/kvm/vmx/vmenter.S
+++ b/arch/x86/kvm/vmx/vmenter.S
@@ -44,7 +44,7 @@
* they VM-Fail, whereas a successful VM-Enter + VM-Exit will jump
* to vmx_vmexit.
*/
-SYM_FUNC_START(vmx_vmenter)
+SYM_FUNC_START_LOCAL(vmx_vmenter)
/* EFLAGS.ZF is set if VMCS.LAUNCHED == 0 */
je 2f
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 75c9c6a0a3a4..65b5f02b199f 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6577,8 +6577,6 @@ static fastpath_t vmx_exit_handlers_fastpath(struct kvm_vcpu *vcpu)
}
}
-bool __vmx_vcpu_run(struct vcpu_vmx *vmx, unsigned long *regs, bool launched);
-
static noinstr void vmx_vcpu_enter_exit(struct kvm_vcpu *vcpu,
struct vcpu_vmx *vmx)
{
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 9d3a557949ac..03fc90569ae1 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -339,6 +339,7 @@ void vmx_set_virtual_apic_mode(struct kvm_vcpu *vcpu);
struct vmx_uret_msr *vmx_find_uret_msr(struct vcpu_vmx *vmx, u32 msr);
void pt_update_intercept_for_msr(struct kvm_vcpu *vcpu);
void vmx_update_host_rsp(struct vcpu_vmx *vmx, unsigned long host_rsp);
+bool __vmx_vcpu_run(struct vcpu_vmx *vmx, unsigned long *regs, bool launched);
int vmx_find_loadstore_msr_slot(struct vmx_msrs *m, u32 msr);
void vmx_ept_load_pdptrs(struct kvm_vcpu *vcpu);
--
2.29.2.729.g45daf8777d-goog
