[PATCH 1/4] KVM: x86: refactor req_immediate_exit logic
From: Maxim Levitsky
Date: Wed Aug 30 2023 - 14:56:06 EST
- move req_immediate_exit variable from arch specific to common code.
- remove arch specific callback .request_immediate_exit and move the code
down to the arch's vcpu_run's code.
No functional change is intended.
Signed-off-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
---
arch/x86/include/asm/kvm-x86-ops.h | 1 -
arch/x86/include/asm/kvm_host.h | 5 ++---
arch/x86/kvm/svm/svm.c | 5 +++--
arch/x86/kvm/vmx/vmx.c | 18 ++++++-----------
arch/x86/kvm/vmx/vmx.h | 2 --
arch/x86/kvm/x86.c | 31 +++++++++++-------------------
6 files changed, 22 insertions(+), 40 deletions(-)
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index e3054e3e46d52d..f654a7f4cc8c0c 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -101,7 +101,6 @@ KVM_X86_OP(write_tsc_multiplier)
KVM_X86_OP(get_exit_info)
KVM_X86_OP(check_intercept)
KVM_X86_OP(handle_exit_irqoff)
-KVM_X86_OP(request_immediate_exit)
KVM_X86_OP(sched_in)
KVM_X86_OP_OPTIONAL(update_cpu_dirty_logging)
KVM_X86_OP_OPTIONAL(vcpu_blocking)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 3bc146dfd38da5..5f2a93f92a3df7 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -993,6 +993,8 @@ struct kvm_vcpu_arch {
*/
bool pdptrs_from_userspace;
+ bool req_immediate_exit;
+
#if IS_ENABLED(CONFIG_HYPERV)
hpa_t hv_root_tdp;
#endif
@@ -1672,8 +1674,6 @@ struct kvm_x86_ops {
struct x86_exception *exception);
void (*handle_exit_irqoff)(struct kvm_vcpu *vcpu);
- void (*request_immediate_exit)(struct kvm_vcpu *vcpu);
-
void (*sched_in)(struct kvm_vcpu *kvm, int cpu);
/*
@@ -2157,7 +2157,6 @@ extern bool kvm_find_async_pf_gfn(struct kvm_vcpu *vcpu, gfn_t gfn);
int kvm_skip_emulated_instruction(struct kvm_vcpu *vcpu);
int kvm_complete_insn_gp(struct kvm_vcpu *vcpu, int err);
-void __kvm_request_immediate_exit(struct kvm_vcpu *vcpu);
void __user *__x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa,
u32 size);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 956726d867aafc..18d0895975dfd8 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4063,6 +4063,9 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
clgi();
kvm_load_guest_xsave_state(vcpu);
+ if (vcpu->arch.req_immediate_exit)
+ smp_send_reschedule(vcpu->cpu);
+
kvm_wait_lapic_expire(vcpu);
/*
@@ -4878,8 +4881,6 @@ static struct kvm_x86_ops svm_x86_ops __initdata = {
.check_intercept = svm_check_intercept,
.handle_exit_irqoff = svm_handle_exit_irqoff,
- .request_immediate_exit = __kvm_request_immediate_exit,
-
.sched_in = svm_sched_in,
.nested_ops = &svm_nested_ops,
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index df461f387e20d4..77ef6f02b3f42f 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -68,6 +68,8 @@
#include "x86.h"
#include "smm.h"
+#include <trace/events/ipi.h>
+
MODULE_AUTHOR("Qumranet");
MODULE_LICENSE("GPL");
@@ -1274,8 +1276,6 @@ void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
u16 fs_sel, gs_sel;
int i;
- vmx->req_immediate_exit = false;
-
/*
* Note that guest MSRs to be saved/restored can also be changed
* when guest state is loaded. This happens when guest transitions
@@ -5997,7 +5997,7 @@ static fastpath_t handle_fastpath_preemption_timer(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
- if (!vmx->req_immediate_exit &&
+ if (!vcpu->arch.req_immediate_exit &&
!unlikely(vmx->loaded_vmcs->hv_timer_soft_disabled)) {
kvm_lapic_expired_hv_timer(vcpu);
return EXIT_FASTPATH_REENTER_GUEST;
@@ -7153,7 +7153,7 @@ static void vmx_update_hv_timer(struct kvm_vcpu *vcpu)
u64 tscl;
u32 delta_tsc;
- if (vmx->req_immediate_exit) {
+ if (vcpu->arch.req_immediate_exit) {
vmcs_write32(VMX_PREEMPTION_TIMER_VALUE, 0);
vmx->loaded_vmcs->hv_timer_soft_disabled = false;
} else if (vmx->hv_deadline_tsc != -1) {
@@ -7348,6 +7348,8 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu)
if (enable_preemption_timer)
vmx_update_hv_timer(vcpu);
+ else if (vcpu->arch.req_immediate_exit)
+ smp_send_reschedule(vcpu->cpu);
kvm_wait_lapic_expire(vcpu);
@@ -7892,11 +7894,6 @@ static __init void vmx_set_cpu_caps(void)
kvm_cpu_cap_check_and_set(X86_FEATURE_WAITPKG);
}
-static void vmx_request_immediate_exit(struct kvm_vcpu *vcpu)
-{
- to_vmx(vcpu)->req_immediate_exit = true;
-}
-
static int vmx_check_intercept_io(struct kvm_vcpu *vcpu,
struct x86_instruction_info *info)
{
@@ -8305,8 +8302,6 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = {
.check_intercept = vmx_check_intercept,
.handle_exit_irqoff = vmx_handle_exit_irqoff,
- .request_immediate_exit = vmx_request_immediate_exit,
-
.sched_in = vmx_sched_in,
.cpu_dirty_log_size = PML_ENTITY_NUM,
@@ -8564,7 +8559,6 @@ static __init int hardware_setup(void)
if (!enable_preemption_timer) {
vmx_x86_ops.set_hv_timer = NULL;
vmx_x86_ops.cancel_hv_timer = NULL;
- vmx_x86_ops.request_immediate_exit = __kvm_request_immediate_exit;
}
kvm_caps.supported_mce_cap |= MCG_LMCE_P;
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 32384ba3849949..96c94f69ef8311 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -330,8 +330,6 @@ struct vcpu_vmx {
unsigned int ple_window;
bool ple_window_dirty;
- bool req_immediate_exit;
-
/* Support for PML */
#define PML_ENTITY_NUM 512
struct page *pml_pg;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 278dbd37dab244..53f0a5f493be37 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10052,8 +10052,7 @@ static void kvm_inject_exception(struct kvm_vcpu *vcpu)
* ordering between that side effect, the instruction completing, _and_ the
* delivery of the asynchronous event.
*/
-static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu,
- bool *req_immediate_exit)
+static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu)
{
bool can_inject;
int r;
@@ -10230,8 +10229,9 @@ static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu,
if (is_guest_mode(vcpu) &&
kvm_x86_ops.nested_ops->has_events &&
- kvm_x86_ops.nested_ops->has_events(vcpu))
- *req_immediate_exit = true;
+ kvm_x86_ops.nested_ops->has_events(vcpu)) {
+ vcpu->arch.req_immediate_exit = true;
+ }
/*
* KVM must never queue a new exception while injecting an event; KVM
@@ -10248,10 +10248,9 @@ static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu,
WARN_ON_ONCE(vcpu->arch.exception.pending ||
vcpu->arch.exception_vmexit.pending);
return 0;
-
out:
if (r == -EBUSY) {
- *req_immediate_exit = true;
+ vcpu->arch.req_immediate_exit = true;
r = 0;
}
return r;
@@ -10478,12 +10477,6 @@ static void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu)
static_call_cond(kvm_x86_set_apic_access_page_addr)(vcpu);
}
-void __kvm_request_immediate_exit(struct kvm_vcpu *vcpu)
-{
- smp_send_reschedule(vcpu->cpu);
-}
-EXPORT_SYMBOL_GPL(__kvm_request_immediate_exit);
-
/*
* Called within kvm->srcu read side.
* Returns 1 to let vcpu_run() continue the guest execution loop without
@@ -10498,8 +10491,6 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
kvm_cpu_accept_dm_intr(vcpu);
fastpath_t exit_fastpath;
- bool req_immediate_exit = false;
-
if (kvm_request_pending(vcpu)) {
if (kvm_check_request(KVM_REQ_VM_DEAD, vcpu)) {
r = -EIO;
@@ -10660,7 +10651,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
goto out;
}
- r = kvm_check_and_inject_events(vcpu, &req_immediate_exit);
+ r = kvm_check_and_inject_events(vcpu);
if (r < 0) {
r = 0;
goto out;
@@ -10729,10 +10720,9 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
goto cancel_injection;
}
- if (req_immediate_exit) {
+
+ if (vcpu->arch.req_immediate_exit)
kvm_make_request(KVM_REQ_EVENT, vcpu);
- static_call(kvm_x86_request_immediate_exit)(vcpu);
- }
fpregs_assert_state_consistent();
if (test_thread_flag(TIF_NEED_FPU_LOAD))
@@ -10764,6 +10754,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
(kvm_get_apic_mode(vcpu) != LAPIC_MODE_DISABLED));
exit_fastpath = static_call(kvm_x86_vcpu_run)(vcpu);
+
if (likely(exit_fastpath != EXIT_FASTPATH_REENTER_GUEST))
break;
@@ -10779,6 +10770,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
++vcpu->stat.exits;
}
+ vcpu->arch.req_immediate_exit = false;
/*
* Do this here before restoring debug registers on the host. And
* since we do this before handling the vmexit, a DR access vmexit
@@ -10866,8 +10858,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
return r;
cancel_injection:
- if (req_immediate_exit)
- kvm_make_request(KVM_REQ_EVENT, vcpu);
+ vcpu->arch.req_immediate_exit = false;
static_call(kvm_x86_cancel_injection)(vcpu);
if (unlikely(vcpu->arch.apic_attention))
kvm_lapic_sync_from_vapic(vcpu);
--
2.26.3