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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-changelog] [xen master] SVM: introduce a VM entry helper
commit 3abe241190af31760c506a9f32bf25e958ea060c
Author: Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Mon May 7 09:12:16 2018 +0200
Commit: Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Mon May 7 09:12:16 2018 +0200
SVM: introduce a VM entry helper
Neither the register values copying nor the trace entry generation need
doing in assembly. The VMLOAD invocation can also be further deferred
(and centralized). Therefore replace the svm_asid_handle_vmrun()
invocation with one of the new helper.
Similarly move the VM exit side register value copying into
svm_vmexit_handler().
Now that we always make it out to guest context after VMLOAD,
svm_sync_vmcb() no longer overrides vmcb_needs_vmsave, making
svm_vmexit_handler() setting the field early unnecessary.
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
Acked-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
Release-acked-by: Juergen Gross <jgross@xxxxxxxx>
---
xen/arch/x86/hvm/svm/entry.S | 29 ++-----------------------
xen/arch/x86/hvm/svm/svm.c | 44 +++++++++++++++++++++++---------------
xen/arch/x86/x86_64/asm-offsets.c | 6 ------
xen/include/asm-x86/hvm/svm/asid.h | 1 +
4 files changed, 30 insertions(+), 50 deletions(-)
diff --git a/xen/arch/x86/hvm/svm/entry.S b/xen/arch/x86/hvm/svm/entry.S
index 7d68648c7d..0fa5501477 100644
--- a/xen/arch/x86/hvm/svm/entry.S
+++ b/xen/arch/x86/hvm/svm/entry.S
@@ -61,23 +61,8 @@ UNLIKELY_START(ne, nsvm_hap)
jmp .Lsvm_do_resume
__UNLIKELY_END(nsvm_hap)
- call svm_asid_handle_vmrun
-
- cmpb $0,tb_init_done(%rip)
-UNLIKELY_START(nz, svm_trace)
- call svm_trace_vmentry
-UNLIKELY_END(svm_trace)
-
- mov VCPU_svm_vmcb(%rbx),%rcx
- mov UREGS_rax(%rsp),%rax
- mov %rax,VMCB_rax(%rcx)
- mov UREGS_rip(%rsp),%rax
- mov %rax,VMCB_rip(%rcx)
- mov UREGS_rsp(%rsp),%rax
- mov %rax,VMCB_rsp(%rcx)
- mov UREGS_eflags(%rsp),%rax
- or $X86_EFLAGS_MBS,%rax
- mov %rax,VMCB_rflags(%rcx)
+ mov %rsp, %rdi
+ call svm_vmenter_helper
mov VCPU_arch_msr(%rbx), %rax
mov VCPUMSR_spec_ctrl_raw(%rax), %eax
@@ -111,16 +96,6 @@ UNLIKELY_END(svm_trace)
SPEC_CTRL_ENTRY_FROM_VMEXIT /* Req: b=curr %rsp=regs/cpuinfo, Clob:
acd */
/* WARNING! `ret`, `call *`, `jmp *` not safe before this point. */
- mov VCPU_svm_vmcb(%rbx),%rcx
- mov VMCB_rax(%rcx),%rax
- mov %rax,UREGS_rax(%rsp)
- mov VMCB_rip(%rcx),%rax
- mov %rax,UREGS_rip(%rsp)
- mov VMCB_rsp(%rcx),%rax
- mov %rax,UREGS_rsp(%rsp)
- mov VMCB_rflags(%rcx),%rax
- mov %rax,UREGS_eflags(%rsp)
-
STGI
GLOBAL(svm_stgi_label)
mov %rsp,%rdi
diff --git a/xen/arch/x86/hvm/svm/svm.c b/xen/arch/x86/hvm/svm/svm.c
index 798f0bc4cf..673a38c574 100644
--- a/xen/arch/x86/hvm/svm/svm.c
+++ b/xen/arch/x86/hvm/svm/svm.c
@@ -687,10 +687,9 @@ static void svm_sync_vmcb(struct vcpu *v, enum
vmcb_sync_state new_state)
if ( new_state == vmcb_needs_vmsave )
{
if ( arch_svm->vmcb_sync_state == vmcb_needs_vmload )
- {
svm_vmload(arch_svm->vmcb);
- arch_svm->vmcb_sync_state = vmcb_in_sync;
- }
+
+ arch_svm->vmcb_sync_state = new_state;
}
else
{
@@ -1171,11 +1170,29 @@ static void noreturn svm_do_resume(struct vcpu *v)
hvm_do_resume(v);
- svm_sync_vmcb(v, vmcb_needs_vmsave);
-
reset_stack_and_jump(svm_asm_do_resume);
}
+void svm_vmenter_helper(const struct cpu_user_regs *regs)
+{
+ struct vcpu *curr = current;
+ struct vmcb_struct *vmcb = curr->arch.hvm_svm.vmcb;
+
+ svm_asid_handle_vmrun();
+
+ if ( unlikely(tb_init_done) )
+ HVMTRACE_ND(VMENTRY,
+ nestedhvm_vcpu_in_guestmode(curr) ? TRC_HVM_NESTEDFLAG : 0,
+ 1/*cycles*/, 0, 0, 0, 0, 0, 0, 0);
+
+ svm_sync_vmcb(curr, vmcb_needs_vmsave);
+
+ vmcb->rax = regs->rax;
+ vmcb->rip = regs->rip;
+ vmcb->rsp = regs->rsp;
+ vmcb->rflags = regs->rflags | X86_EFLAGS_MBS;
+}
+
static void svm_guest_osvw_init(struct vcpu *vcpu)
{
if ( boot_cpu_data.x86_vendor != X86_VENDOR_AMD )
@@ -2621,7 +2638,11 @@ void svm_vmexit_handler(struct cpu_user_regs *regs)
bool_t vcpu_guestmode = 0;
struct vlapic *vlapic = vcpu_vlapic(v);
- v->arch.hvm_svm.vmcb_sync_state = vmcb_needs_vmsave;
+ regs->rax = vmcb->rax;
+ regs->rip = vmcb->rip;
+ regs->rsp = vmcb->rsp;
+ regs->rflags = vmcb->rflags;
+
hvm_invalidate_regs_fields(regs);
if ( paging_mode_hap(v->domain) )
@@ -3108,8 +3129,6 @@ void svm_vmexit_handler(struct cpu_user_regs *regs)
}
out:
- svm_sync_vmcb(v, vmcb_needs_vmsave);
-
if ( vcpu_guestmode || vlapic_hw_disabled(vlapic) )
return;
@@ -3118,17 +3137,8 @@ void svm_vmexit_handler(struct cpu_user_regs *regs)
intr.fields.tpr =
(vlapic_get_reg(vlapic, APIC_TASKPRI) & 0xFF) >> 4;
vmcb_set_vintr(vmcb, intr);
- ASSERT(v->arch.hvm_svm.vmcb_sync_state != vmcb_needs_vmload);
}
-void svm_trace_vmentry(void)
-{
- struct vcpu *curr = current;
- HVMTRACE_ND(VMENTRY,
- nestedhvm_vcpu_in_guestmode(curr) ? TRC_HVM_NESTEDFLAG : 0,
- 1/*cycles*/, 0, 0, 0, 0, 0, 0, 0);
-}
-
/*
* Local variables:
* mode: C
diff --git a/xen/arch/x86/x86_64/asm-offsets.c
b/xen/arch/x86/x86_64/asm-offsets.c
index eb7e77619a..06028febc1 100644
--- a/xen/arch/x86/x86_64/asm-offsets.c
+++ b/xen/arch/x86/x86_64/asm-offsets.c
@@ -119,12 +119,6 @@ void __dummy__(void)
OFFSET(DOMAIN_is_32bit_pv, struct domain, arch.is_32bit_pv);
BLANK();
- OFFSET(VMCB_rax, struct vmcb_struct, rax);
- OFFSET(VMCB_rip, struct vmcb_struct, rip);
- OFFSET(VMCB_rsp, struct vmcb_struct, rsp);
- OFFSET(VMCB_rflags, struct vmcb_struct, rflags);
- BLANK();
-
OFFSET(VCPUINFO_upcall_pending, struct vcpu_info, evtchn_upcall_pending);
OFFSET(VCPUINFO_upcall_mask, struct vcpu_info, evtchn_upcall_mask);
BLANK();
diff --git a/xen/include/asm-x86/hvm/svm/asid.h
b/xen/include/asm-x86/hvm/svm/asid.h
index 154f4da5fb..d3a144cb6b 100644
--- a/xen/include/asm-x86/hvm/svm/asid.h
+++ b/xen/include/asm-x86/hvm/svm/asid.h
@@ -23,6 +23,7 @@
#include <asm/processor.h>
void svm_asid_init(const struct cpuinfo_x86 *c);
+void svm_asid_handle_vmrun(void);
static inline void svm_asid_g_invlpg(struct vcpu *v, unsigned long g_vaddr)
{
--
generated by git-patchbot for /home/xen/git/xen.git#master
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