* [PATCH 1/9] KVM: x86: set TMR when the interrupt is accepted
2015-08-05 15:23 [PATCH 0/9] split irqchip series Paolo Bonzini
@ 2015-08-05 15:23 ` Paolo Bonzini
2015-08-05 15:23 ` [PATCH 2/9] KVM: x86: store IOAPIC-handled vectors in each VCPU Paolo Bonzini
` (7 subsequent siblings)
8 siblings, 0 replies; 17+ messages in thread
From: Paolo Bonzini @ 2015-08-05 15:23 UTC (permalink / raw)
To: linux-kernel, kvm; +Cc: Steve Rutherford, rkrcmar
Do not compute TMR in advance. Instead, set the TMR just before the interrupt
is accepted into the IRR. This limits the coupling between IOAPIC and LAPIC.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/ioapic.c | 9 ++-------
arch/x86/kvm/ioapic.h | 3 +--
arch/x86/kvm/lapic.c | 19 ++++++++++---------
arch/x86/kvm/lapic.h | 1 -
arch/x86/kvm/x86.c | 5 +----
5 files changed, 14 insertions(+), 23 deletions(-)
diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
index 856f79105bb5..eaf4ec38d980 100644
--- a/arch/x86/kvm/ioapic.c
+++ b/arch/x86/kvm/ioapic.c
@@ -246,8 +246,7 @@ static void update_handled_vectors(struct kvm_ioapic *ioapic)
smp_wmb();
}
-void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap,
- u32 *tmr)
+void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
{
struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
union kvm_ioapic_redirect_entry *e;
@@ -260,13 +259,9 @@ void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap,
kvm_irq_has_notifier(ioapic->kvm, KVM_IRQCHIP_IOAPIC, index) ||
index == RTC_GSI) {
if (kvm_apic_match_dest(vcpu, NULL, 0,
- e->fields.dest_id, e->fields.dest_mode)) {
+ e->fields.dest_id, e->fields.dest_mode))
__set_bit(e->fields.vector,
(unsigned long *)eoi_exit_bitmap);
- if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG)
- __set_bit(e->fields.vector,
- (unsigned long *)tmr);
- }
}
}
spin_unlock(&ioapic->lock);
diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h
index ca0b0b4e6256..3dbd0e2aac4e 100644
--- a/arch/x86/kvm/ioapic.h
+++ b/arch/x86/kvm/ioapic.h
@@ -120,7 +120,6 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
struct kvm_lapic_irq *irq, unsigned long *dest_map);
int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
-void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap,
- u32 *tmr);
+void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
#endif
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 2a5ca97c263b..9be64c77d6db 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -551,15 +551,6 @@ static void pv_eoi_clr_pending(struct kvm_vcpu *vcpu)
__clear_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention);
}
-void kvm_apic_update_tmr(struct kvm_vcpu *vcpu, u32 *tmr)
-{
- struct kvm_lapic *apic = vcpu->arch.apic;
- int i;
-
- for (i = 0; i < 8; i++)
- apic_set_reg(apic, APIC_TMR + 0x10 * i, tmr[i]);
-}
-
static void apic_update_ppr(struct kvm_lapic *apic)
{
u32 tpr, isrv, ppr, old_ppr;
@@ -781,6 +772,9 @@ static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
case APIC_DM_LOWEST:
vcpu->arch.apic_arb_prio++;
case APIC_DM_FIXED:
+ if (unlikely(trig_mode && !level))
+ break;
+
/* FIXME add logic for vcpu on reset */
if (unlikely(!apic_enabled(apic)))
break;
@@ -790,6 +784,13 @@ static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
if (dest_map)
__set_bit(vcpu->vcpu_id, dest_map);
+ if (apic_test_vector(vector, apic->regs + APIC_TMR) != !!trig_mode) {
+ if (trig_mode)
+ apic_set_vector(vector, apic->regs + APIC_TMR);
+ else
+ apic_clear_vector(vector, apic->regs + APIC_TMR);
+ }
+
if (kvm_x86_ops->deliver_posted_interrupt)
kvm_x86_ops->deliver_posted_interrupt(vcpu, vector);
else {
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index 764037991d26..eb46d6bcaa75 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -57,7 +57,6 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value);
u64 kvm_lapic_get_base(struct kvm_vcpu *vcpu);
void kvm_apic_set_version(struct kvm_vcpu *vcpu);
-void kvm_apic_update_tmr(struct kvm_vcpu *vcpu, u32 *tmr);
void __kvm_apic_update_irr(u32 *pir, void *regs);
void kvm_apic_update_irr(struct kvm_vcpu *vcpu, u32 *pir);
int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c7b6aed998e9..9e29dbe183d7 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6150,17 +6150,14 @@ static void process_smi(struct kvm_vcpu *vcpu)
static void vcpu_scan_ioapic(struct kvm_vcpu *vcpu)
{
u64 eoi_exit_bitmap[4];
- u32 tmr[8];
if (!kvm_apic_hw_enabled(vcpu->arch.apic))
return;
memset(eoi_exit_bitmap, 0, 32);
- memset(tmr, 0, 32);
- kvm_ioapic_scan_entry(vcpu, eoi_exit_bitmap, tmr);
+ kvm_ioapic_scan_entry(vcpu, eoi_exit_bitmap);
kvm_x86_ops->load_eoi_exitmap(vcpu, eoi_exit_bitmap);
- kvm_apic_update_tmr(vcpu, tmr);
}
static void kvm_vcpu_flush_tlb(struct kvm_vcpu *vcpu)
--
1.8.3.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 2/9] KVM: x86: store IOAPIC-handled vectors in each VCPU
2015-08-05 15:23 [PATCH 0/9] split irqchip series Paolo Bonzini
2015-08-05 15:23 ` [PATCH 1/9] KVM: x86: set TMR when the interrupt is accepted Paolo Bonzini
@ 2015-08-05 15:23 ` Paolo Bonzini
2015-08-05 15:23 ` [PATCH 3/9] KVM: x86: replace vm_has_apicv hook with cpu_uses_apicv Paolo Bonzini
` (6 subsequent siblings)
8 siblings, 0 replies; 17+ messages in thread
From: Paolo Bonzini @ 2015-08-05 15:23 UTC (permalink / raw)
To: linux-kernel, kvm; +Cc: Steve Rutherford, rkrcmar
We can reuse the algorithm that computes the EOI exit bitmap to figure
out which vectors are handled by the IOAPIC. The only difference
between the two is for edge-triggered interrupts other than IRQ8
that have no notifiers active; however, the IOAPIC does not have to
do anything special for these interrupts anyway.
This again limits the interactions between the IOAPIC and the LAPIC,
making it easier to move the former to userspace.
Inspired by a patch from Steve Rutherford.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/include/asm/kvm_host.h | 3 ++-
arch/x86/kvm/ioapic.c | 18 ++----------------
arch/x86/kvm/ioapic.h | 8 --------
arch/x86/kvm/lapic.c | 10 ++++++++--
arch/x86/kvm/svm.c | 2 +-
arch/x86/kvm/vmx.c | 3 ++-
arch/x86/kvm/x86.c | 8 +++-----
7 files changed, 18 insertions(+), 34 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index c12e845f59e6..bf7828a58cdc 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -395,6 +395,7 @@ struct kvm_vcpu_arch {
u64 efer;
u64 apic_base;
struct kvm_lapic *apic; /* kernel irqchip context */
+ u64 eoi_exit_bitmap[4];
unsigned long apic_attention;
int32_t apic_arb_prio;
int mp_state;
@@ -820,7 +821,7 @@ struct kvm_x86_ops {
int (*vm_has_apicv)(struct kvm *kvm);
void (*hwapic_irr_update)(struct kvm_vcpu *vcpu, int max_irr);
void (*hwapic_isr_update)(struct kvm *kvm, int isr);
- void (*load_eoi_exitmap)(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
+ void (*load_eoi_exitmap)(struct kvm_vcpu *vcpu);
void (*set_virtual_x2apic_mode)(struct kvm_vcpu *vcpu, bool set);
void (*set_apic_access_page_addr)(struct kvm_vcpu *vcpu, hpa_t hpa);
void (*deliver_posted_interrupt)(struct kvm_vcpu *vcpu, int vector);
diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
index eaf4ec38d980..2dcda0f188ba 100644
--- a/arch/x86/kvm/ioapic.c
+++ b/arch/x86/kvm/ioapic.c
@@ -233,19 +233,6 @@ static void kvm_ioapic_inject_all(struct kvm_ioapic *ioapic, unsigned long irr)
}
-static void update_handled_vectors(struct kvm_ioapic *ioapic)
-{
- DECLARE_BITMAP(handled_vectors, 256);
- int i;
-
- memset(handled_vectors, 0, sizeof(handled_vectors));
- for (i = 0; i < IOAPIC_NUM_PINS; ++i)
- __set_bit(ioapic->redirtbl[i].fields.vector, handled_vectors);
- memcpy(ioapic->handled_vectors, handled_vectors,
- sizeof(handled_vectors));
- smp_wmb();
-}
-
void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
{
struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
@@ -310,7 +297,6 @@ static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
e->bits |= (u32) val;
e->fields.remote_irr = 0;
}
- update_handled_vectors(ioapic);
mask_after = e->fields.mask;
if (mask_before != mask_after)
kvm_fire_mask_notifiers(ioapic->kvm, KVM_IRQCHIP_IOAPIC, index, mask_after);
@@ -594,7 +580,6 @@ static void kvm_ioapic_reset(struct kvm_ioapic *ioapic)
ioapic->id = 0;
memset(ioapic->irq_eoi, 0x00, IOAPIC_NUM_PINS);
rtc_irq_eoi_tracking_reset(ioapic);
- update_handled_vectors(ioapic);
}
static const struct kvm_io_device_ops ioapic_mmio_ops = {
@@ -623,8 +608,10 @@ int kvm_ioapic_init(struct kvm *kvm)
if (ret < 0) {
kvm->arch.vioapic = NULL;
kfree(ioapic);
+ return ret;
}
+ kvm_vcpu_request_scan_ioapic(kvm);
return ret;
}
@@ -661,7 +648,6 @@ int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
memcpy(ioapic, state, sizeof(struct kvm_ioapic_state));
ioapic->irr = 0;
ioapic->irr_delivered = 0;
- update_handled_vectors(ioapic);
kvm_vcpu_request_scan_ioapic(kvm);
kvm_ioapic_inject_all(ioapic, state->irr);
spin_unlock(&ioapic->lock);
diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h
index 3dbd0e2aac4e..bf36d66a1951 100644
--- a/arch/x86/kvm/ioapic.h
+++ b/arch/x86/kvm/ioapic.h
@@ -73,7 +73,6 @@ struct kvm_ioapic {
struct kvm *kvm;
void (*ack_notifier)(void *opaque, int irq);
spinlock_t lock;
- DECLARE_BITMAP(handled_vectors, 256);
struct rtc_status rtc_status;
struct delayed_work eoi_inject;
u32 irq_eoi[IOAPIC_NUM_PINS];
@@ -98,13 +97,6 @@ static inline struct kvm_ioapic *ioapic_irqchip(struct kvm *kvm)
return kvm->arch.vioapic;
}
-static inline bool kvm_ioapic_handles_vector(struct kvm *kvm, int vector)
-{
- struct kvm_ioapic *ioapic = kvm->arch.vioapic;
- smp_rmb();
- return test_bit(vector, ioapic->handled_vectors);
-}
-
void kvm_rtc_eoi_tracking_restore_one(struct kvm_vcpu *vcpu);
bool kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
int short_hand, unsigned int dest, int dest_mode);
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 9be64c77d6db..c158f4667aa3 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -869,14 +869,20 @@ int kvm_apic_compare_prio(struct kvm_vcpu *vcpu1, struct kvm_vcpu *vcpu2)
return vcpu1->arch.apic_arb_prio - vcpu2->arch.apic_arb_prio;
}
+static bool kvm_ioapic_handles_vector(struct kvm_lapic *apic, int vector)
+{
+ return test_bit(vector, (ulong *)apic->vcpu->arch.eoi_exit_bitmap);
+}
+
static void kvm_ioapic_send_eoi(struct kvm_lapic *apic, int vector)
{
- if (kvm_ioapic_handles_vector(apic->vcpu->kvm, vector)) {
+ if (kvm_ioapic_handles_vector(apic, vector)) {
int trigger_mode;
if (apic_test_vector(vector, apic->regs + APIC_TMR))
trigger_mode = IOAPIC_LEVEL_TRIG;
else
trigger_mode = IOAPIC_EDGE_TRIG;
+
kvm_ioapic_update_eoi(apic->vcpu, vector, trigger_mode);
}
}
@@ -1922,7 +1928,7 @@ static void apic_sync_pv_eoi_to_guest(struct kvm_vcpu *vcpu,
/* Cache not set: could be safe but we don't bother. */
apic->highest_isr_cache == -1 ||
/* Need EOI to update ioapic. */
- kvm_ioapic_handles_vector(vcpu->kvm, apic->highest_isr_cache)) {
+ kvm_ioapic_handles_vector(apic, apic->highest_isr_cache)) {
/*
* PV EOI was disabled by apic_sync_pv_eoi_from_guest
* so we need not do anything here.
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 74d825716f4f..b950fda937cf 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -3766,7 +3766,7 @@ static int svm_vm_has_apicv(struct kvm *kvm)
return 0;
}
-static void svm_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
+static void svm_load_eoi_exitmap(struct kvm_vcpu *vcpu)
{
return;
}
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 37eae551857c..a7a62cfc1886 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -8041,8 +8041,9 @@ static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)
}
}
-static void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
+static void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu)
{
+ u64 *eoi_exit_bitmap = vcpu->arch.eoi_exit_bitmap;
if (!vmx_vm_has_apicv(vcpu->kvm))
return;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 9e29dbe183d7..394f65aa4e1c 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6149,15 +6149,13 @@ static void process_smi(struct kvm_vcpu *vcpu)
static void vcpu_scan_ioapic(struct kvm_vcpu *vcpu)
{
- u64 eoi_exit_bitmap[4];
-
if (!kvm_apic_hw_enabled(vcpu->arch.apic))
return;
- memset(eoi_exit_bitmap, 0, 32);
+ memset(vcpu->arch.eoi_exit_bitmap, 0, 256 / 8);
- kvm_ioapic_scan_entry(vcpu, eoi_exit_bitmap);
- kvm_x86_ops->load_eoi_exitmap(vcpu, eoi_exit_bitmap);
+ kvm_ioapic_scan_entry(vcpu, vcpu->arch.eoi_exit_bitmap);
+ kvm_x86_ops->load_eoi_exitmap(vcpu);
}
static void kvm_vcpu_flush_tlb(struct kvm_vcpu *vcpu)
--
1.8.3.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 3/9] KVM: x86: replace vm_has_apicv hook with cpu_uses_apicv
2015-08-05 15:23 [PATCH 0/9] split irqchip series Paolo Bonzini
2015-08-05 15:23 ` [PATCH 1/9] KVM: x86: set TMR when the interrupt is accepted Paolo Bonzini
2015-08-05 15:23 ` [PATCH 2/9] KVM: x86: store IOAPIC-handled vectors in each VCPU Paolo Bonzini
@ 2015-08-05 15:23 ` Paolo Bonzini
2015-08-05 15:23 ` [PATCH 4/9] KVM: x86: introduce lapic_in_kernel Paolo Bonzini
` (5 subsequent siblings)
8 siblings, 0 replies; 17+ messages in thread
From: Paolo Bonzini @ 2015-08-05 15:23 UTC (permalink / raw)
To: linux-kernel, kvm; +Cc: Steve Rutherford, rkrcmar
This will avoid an unnecessary trip to ->kvm and from there to the VPIC.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/include/asm/kvm_host.h | 2 +-
arch/x86/kvm/irq.c | 2 +-
arch/x86/kvm/lapic.c | 4 ++--
arch/x86/kvm/lapic.h | 4 ++--
arch/x86/kvm/svm.c | 4 ++--
arch/x86/kvm/vmx.c | 8 +++++++-
6 files changed, 15 insertions(+), 9 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index bf7828a58cdc..deeb98617e22 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -818,7 +818,7 @@ struct kvm_x86_ops {
void (*enable_nmi_window)(struct kvm_vcpu *vcpu);
void (*enable_irq_window)(struct kvm_vcpu *vcpu);
void (*update_cr8_intercept)(struct kvm_vcpu *vcpu, int tpr, int irr);
- int (*vm_has_apicv)(struct kvm *kvm);
+ int (*cpu_uses_apicv)(struct kvm_vcpu *vcpu);
void (*hwapic_irr_update)(struct kvm_vcpu *vcpu, int max_irr);
void (*hwapic_isr_update)(struct kvm *kvm, int isr);
void (*load_eoi_exitmap)(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index a1ec6a50a05a..c0dad893dc59 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -63,7 +63,7 @@ int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v)
if (kvm_cpu_has_extint(v))
return 1;
- if (kvm_apic_vid_enabled(v->kvm))
+ if (kvm_vcpu_apic_vid_enabled(v))
return 0;
return kvm_apic_has_interrupt(v) != -1; /* LAPIC */
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index c158f4667aa3..ab28cb40d51b 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -390,7 +390,7 @@ static inline void apic_clear_irr(int vec, struct kvm_lapic *apic)
vcpu = apic->vcpu;
- if (unlikely(kvm_apic_vid_enabled(vcpu->kvm))) {
+ if (unlikely(kvm_vcpu_apic_vid_enabled(vcpu))) {
/* try to update RVI */
apic_clear_vector(vec, apic->regs + APIC_IRR);
kvm_make_request(KVM_REQ_EVENT, vcpu);
@@ -1622,7 +1622,7 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
apic_set_reg(apic, APIC_ISR + 0x10 * i, 0);
apic_set_reg(apic, APIC_TMR + 0x10 * i, 0);
}
- apic->irr_pending = kvm_apic_vid_enabled(vcpu->kvm);
+ apic->irr_pending = kvm_vcpu_apic_vid_enabled(vcpu);
apic->isr_count = kvm_x86_ops->hwapic_isr_update ? 1 : 0;
apic->highest_isr_cache = -1;
update_divide_count(apic);
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index eb46d6bcaa75..7259d272416f 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -143,9 +143,9 @@ static inline int apic_x2apic_mode(struct kvm_lapic *apic)
return apic->vcpu->arch.apic_base & X2APIC_ENABLE;
}
-static inline bool kvm_apic_vid_enabled(struct kvm *kvm)
+static inline bool kvm_vcpu_apic_vid_enabled(struct kvm_vcpu *vcpu)
{
- return kvm_x86_ops->vm_has_apicv(kvm);
+ return kvm_x86_ops->cpu_uses_apicv(vcpu);
}
static inline bool kvm_apic_has_events(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index b950fda937cf..a617fd47bdd5 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -3761,7 +3761,7 @@ static void svm_set_virtual_x2apic_mode(struct kvm_vcpu *vcpu, bool set)
return;
}
-static int svm_vm_has_apicv(struct kvm *kvm)
+static int svm_cpu_uses_apicv(struct kvm_vcpu *vcpu)
{
return 0;
}
@@ -4522,7 +4522,7 @@ static struct kvm_x86_ops svm_x86_ops = {
.enable_irq_window = enable_irq_window,
.update_cr8_intercept = update_cr8_intercept,
.set_virtual_x2apic_mode = svm_set_virtual_x2apic_mode,
- .vm_has_apicv = svm_vm_has_apicv,
+ .cpu_uses_apicv = svm_cpu_uses_apicv,
.load_eoi_exitmap = svm_load_eoi_exitmap,
.sync_pir_to_irr = svm_sync_pir_to_irr,
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index a7a62cfc1886..d1561e82540f 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -810,6 +810,7 @@ static void kvm_cpu_vmxoff(void);
static bool vmx_mpx_supported(void);
static bool vmx_xsaves_supported(void);
static int vmx_vm_has_apicv(struct kvm *kvm);
+static int vmx_cpu_uses_apicv(struct kvm_vcpu *vcpu);
static int vmx_set_tss_addr(struct kvm *kvm, unsigned int addr);
static void vmx_set_segment(struct kvm_vcpu *vcpu,
struct kvm_segment *var, int seg);
@@ -4337,6 +4338,11 @@ static int vmx_vm_has_apicv(struct kvm *kvm)
return enable_apicv && irqchip_in_kernel(kvm);
}
+static int vmx_cpu_uses_apicv(struct kvm_vcpu *vcpu)
+{
+ return vmx_vm_has_apicv(vcpu->kvm);
+}
+
static int vmx_complete_nested_posted_interrupt(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -10355,7 +10361,7 @@ static struct kvm_x86_ops vmx_x86_ops = {
.update_cr8_intercept = update_cr8_intercept,
.set_virtual_x2apic_mode = vmx_set_virtual_x2apic_mode,
.set_apic_access_page_addr = vmx_set_apic_access_page_addr,
- .vm_has_apicv = vmx_vm_has_apicv,
+ .cpu_uses_apicv = vmx_cpu_uses_apicv,
.load_eoi_exitmap = vmx_load_eoi_exitmap,
.hwapic_irr_update = vmx_hwapic_irr_update,
.hwapic_isr_update = vmx_hwapic_isr_update,
--
1.8.3.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 4/9] KVM: x86: introduce lapic_in_kernel
2015-08-05 15:23 [PATCH 0/9] split irqchip series Paolo Bonzini
` (2 preceding siblings ...)
2015-08-05 15:23 ` [PATCH 3/9] KVM: x86: replace vm_has_apicv hook with cpu_uses_apicv Paolo Bonzini
@ 2015-08-05 15:23 ` Paolo Bonzini
2015-08-05 15:23 ` [PATCH 5/9] KVM: x86: unify handling of interrupt window Paolo Bonzini
` (4 subsequent siblings)
8 siblings, 0 replies; 17+ messages in thread
From: Paolo Bonzini @ 2015-08-05 15:23 UTC (permalink / raw)
To: linux-kernel, kvm; +Cc: Steve Rutherford, rkrcmar
Avoid pointer chasing and memory barriers, and simplify the code
when split irqchip (LAPIC in kernel, IOAPIC/PIC in userspace)
is introduced.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/irq.c | 6 +++---
arch/x86/kvm/irq.h | 8 ++++++++
arch/x86/kvm/lapic.c | 4 ++--
arch/x86/kvm/mmu.c | 2 +-
arch/x86/kvm/svm.c | 4 ++--
arch/x86/kvm/vmx.c | 46 ++++++++++++++++++++--------------------------
arch/x86/kvm/x86.c | 18 +++++++++---------
7 files changed, 45 insertions(+), 43 deletions(-)
diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index c0dad893dc59..b653ae202c8e 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -57,7 +57,7 @@ static int kvm_cpu_has_extint(struct kvm_vcpu *v)
*/
int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v)
{
- if (!irqchip_in_kernel(v->kvm))
+ if (!lapic_in_kernel(v))
return v->arch.interrupt.pending;
if (kvm_cpu_has_extint(v))
@@ -75,7 +75,7 @@ int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v)
*/
int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
{
- if (!irqchip_in_kernel(v->kvm))
+ if (!lapic_in_kernel(v))
return v->arch.interrupt.pending;
if (kvm_cpu_has_extint(v))
@@ -103,7 +103,7 @@ int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
{
int vector;
- if (!irqchip_in_kernel(v->kvm))
+ if (!lapic_in_kernel(v))
return v->arch.interrupt.nr;
vector = kvm_cpu_get_extint(v);
diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index 3d782a2c336a..9e6e7e04de98 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -92,6 +92,14 @@ static inline int irqchip_in_kernel(struct kvm *kvm)
return vpic != NULL;
}
+static inline int lapic_in_kernel(struct kvm_vcpu *vcpu)
+{
+ /* Same as irqchip_in_kernel(vcpu->kvm), but with less
+ * pointer chasing and no unnecessary memory barriers.
+ */
+ return vcpu->arch.apic != NULL;
+}
+
void kvm_pic_reset(struct kvm_kpic_state *s);
void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index ab28cb40d51b..5cae917451f9 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1984,7 +1984,7 @@ int kvm_x2apic_msr_write(struct kvm_vcpu *vcpu, u32 msr, u64 data)
struct kvm_lapic *apic = vcpu->arch.apic;
u32 reg = (msr - APIC_BASE_MSR) << 4;
- if (!irqchip_in_kernel(vcpu->kvm) || !apic_x2apic_mode(apic))
+ if (!lapic_in_kernel(vcpu) || !apic_x2apic_mode(apic))
return 1;
if (reg == APIC_ICR2)
@@ -2001,7 +2001,7 @@ int kvm_x2apic_msr_read(struct kvm_vcpu *vcpu, u32 msr, u64 *data)
struct kvm_lapic *apic = vcpu->arch.apic;
u32 reg = (msr - APIC_BASE_MSR) << 4, low, high = 0;
- if (!irqchip_in_kernel(vcpu->kvm) || !apic_x2apic_mode(apic))
+ if (!lapic_in_kernel(vcpu) || !apic_x2apic_mode(apic))
return 1;
if (reg == APIC_DFR || reg == APIC_ICR2) {
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index fb16a8ea3dee..70c375f4a79a 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -3426,7 +3426,7 @@ static int kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn)
static bool can_do_async_pf(struct kvm_vcpu *vcpu)
{
- if (unlikely(!irqchip_in_kernel(vcpu->kvm) ||
+ if (unlikely(!lapic_in_kernel(vcpu) ||
kvm_event_needs_reinjection(vcpu)))
return false;
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index a617fd47bdd5..222439fd73d4 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -3152,7 +3152,7 @@ static int cr8_write_interception(struct vcpu_svm *svm)
u8 cr8_prev = kvm_get_cr8(&svm->vcpu);
/* instruction emulation calls kvm_set_cr8() */
r = cr_interception(svm);
- if (irqchip_in_kernel(svm->vcpu.kvm))
+ if (lapic_in_kernel(&svm->vcpu))
return r;
if (cr8_prev <= kvm_get_cr8(&svm->vcpu))
return r;
@@ -3407,7 +3407,7 @@ static int interrupt_window_interception(struct vcpu_svm *svm)
* If the user space waits to inject interrupts, exit as soon as
* possible
*/
- if (!irqchip_in_kernel(svm->vcpu.kvm) &&
+ if (!lapic_in_kernel(&svm->vcpu) &&
kvm_run->request_interrupt_window &&
!kvm_cpu_has_interrupt(&svm->vcpu)) {
kvm_run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index d1561e82540f..ef15dc72284b 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -809,7 +809,6 @@ static void kvm_cpu_vmxon(u64 addr);
static void kvm_cpu_vmxoff(void);
static bool vmx_mpx_supported(void);
static bool vmx_xsaves_supported(void);
-static int vmx_vm_has_apicv(struct kvm *kvm);
static int vmx_cpu_uses_apicv(struct kvm_vcpu *vcpu);
static int vmx_set_tss_addr(struct kvm *kvm, unsigned int addr);
static void vmx_set_segment(struct kvm_vcpu *vcpu,
@@ -947,9 +946,9 @@ static inline bool cpu_has_vmx_tpr_shadow(void)
return vmcs_config.cpu_based_exec_ctrl & CPU_BASED_TPR_SHADOW;
}
-static inline bool vm_need_tpr_shadow(struct kvm *kvm)
+static inline bool cpu_need_tpr_shadow(struct kvm_vcpu *vcpu)
{
- return (cpu_has_vmx_tpr_shadow()) && (irqchip_in_kernel(kvm));
+ return cpu_has_vmx_tpr_shadow() && lapic_in_kernel(vcpu);
}
static inline bool cpu_has_secondary_exec_ctrls(void)
@@ -1063,9 +1062,9 @@ static inline bool cpu_has_vmx_ple(void)
SECONDARY_EXEC_PAUSE_LOOP_EXITING;
}
-static inline bool vm_need_virtualize_apic_accesses(struct kvm *kvm)
+static inline bool cpu_need_virtualize_apic_accesses(struct kvm_vcpu *vcpu)
{
- return flexpriority_enabled && irqchip_in_kernel(kvm);
+ return flexpriority_enabled && lapic_in_kernel(vcpu);
}
static inline bool cpu_has_vmx_vpid(void)
@@ -2378,7 +2377,7 @@ static void nested_vmx_setup_ctls_msrs(struct vcpu_vmx *vmx)
vmx->nested.nested_vmx_pinbased_ctls_high |=
PIN_BASED_ALWAYSON_WITHOUT_TRUE_MSR |
PIN_BASED_VMX_PREEMPTION_TIMER;
- if (vmx_vm_has_apicv(vmx->vcpu.kvm))
+ if (vmx_cpu_uses_apicv(&vmx->vcpu))
vmx->nested.nested_vmx_pinbased_ctls_high |=
PIN_BASED_POSTED_INTR;
@@ -4333,14 +4332,9 @@ static void vmx_disable_intercept_msr_write_x2apic(u32 msr)
msr, MSR_TYPE_W);
}
-static int vmx_vm_has_apicv(struct kvm *kvm)
-{
- return enable_apicv && irqchip_in_kernel(kvm);
-}
-
static int vmx_cpu_uses_apicv(struct kvm_vcpu *vcpu)
{
- return vmx_vm_has_apicv(vcpu->kvm);
+ return enable_apicv && lapic_in_kernel(vcpu);
}
static int vmx_complete_nested_posted_interrupt(struct kvm_vcpu *vcpu)
@@ -4520,7 +4514,7 @@ static u32 vmx_pin_based_exec_ctrl(struct vcpu_vmx *vmx)
{
u32 pin_based_exec_ctrl = vmcs_config.pin_based_exec_ctrl;
- if (!vmx_vm_has_apicv(vmx->vcpu.kvm))
+ if (!vmx_cpu_uses_apicv(&vmx->vcpu))
pin_based_exec_ctrl &= ~PIN_BASED_POSTED_INTR;
return pin_based_exec_ctrl;
}
@@ -4532,7 +4526,7 @@ static u32 vmx_exec_control(struct vcpu_vmx *vmx)
if (vmx->vcpu.arch.switch_db_regs & KVM_DEBUGREG_WONT_EXIT)
exec_control &= ~CPU_BASED_MOV_DR_EXITING;
- if (!vm_need_tpr_shadow(vmx->vcpu.kvm)) {
+ if (!cpu_need_tpr_shadow(&vmx->vcpu)) {
exec_control &= ~CPU_BASED_TPR_SHADOW;
#ifdef CONFIG_X86_64
exec_control |= CPU_BASED_CR8_STORE_EXITING |
@@ -4549,7 +4543,7 @@ static u32 vmx_exec_control(struct vcpu_vmx *vmx)
static u32 vmx_secondary_exec_control(struct vcpu_vmx *vmx)
{
u32 exec_control = vmcs_config.cpu_based_2nd_exec_ctrl;
- if (!vm_need_virtualize_apic_accesses(vmx->vcpu.kvm))
+ if (!cpu_need_virtualize_apic_accesses(&vmx->vcpu))
exec_control &= ~SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES;
if (vmx->vpid == 0)
exec_control &= ~SECONDARY_EXEC_ENABLE_VPID;
@@ -4563,7 +4557,7 @@ static u32 vmx_secondary_exec_control(struct vcpu_vmx *vmx)
exec_control &= ~SECONDARY_EXEC_UNRESTRICTED_GUEST;
if (!ple_gap)
exec_control &= ~SECONDARY_EXEC_PAUSE_LOOP_EXITING;
- if (!vmx_vm_has_apicv(vmx->vcpu.kvm))
+ if (!vmx_cpu_uses_apicv(&vmx->vcpu))
exec_control &= ~(SECONDARY_EXEC_APIC_REGISTER_VIRT |
SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY);
exec_control &= ~SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE;
@@ -4624,7 +4618,7 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
vmx_secondary_exec_control(vmx));
}
- if (vmx_vm_has_apicv(vmx->vcpu.kvm)) {
+ if (vmx_cpu_uses_apicv(&vmx->vcpu)) {
vmcs_write64(EOI_EXIT_BITMAP0, 0);
vmcs_write64(EOI_EXIT_BITMAP1, 0);
vmcs_write64(EOI_EXIT_BITMAP2, 0);
@@ -4768,7 +4762,7 @@ static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
if (cpu_has_vmx_tpr_shadow() && !init_event) {
vmcs_write64(VIRTUAL_APIC_PAGE_ADDR, 0);
- if (vm_need_tpr_shadow(vcpu->kvm))
+ if (cpu_need_tpr_shadow(vcpu))
vmcs_write64(VIRTUAL_APIC_PAGE_ADDR,
__pa(vcpu->arch.apic->regs));
vmcs_write32(TPR_THRESHOLD, 0);
@@ -4776,7 +4770,7 @@ static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
kvm_make_request(KVM_REQ_APIC_PAGE_RELOAD, vcpu);
- if (vmx_vm_has_apicv(vcpu->kvm))
+ if (vmx_cpu_uses_apicv(vcpu))
memset(&vmx->pi_desc, 0, sizeof(struct pi_desc));
if (vmx->vpid != 0)
@@ -5316,7 +5310,7 @@ static int handle_cr(struct kvm_vcpu *vcpu)
u8 cr8 = (u8)val;
err = kvm_set_cr8(vcpu, cr8);
kvm_complete_insn_gp(vcpu, err);
- if (irqchip_in_kernel(vcpu->kvm))
+ if (lapic_in_kernel(vcpu))
return 1;
if (cr8_prev <= cr8)
return 1;
@@ -5535,7 +5529,7 @@ static int handle_interrupt_window(struct kvm_vcpu *vcpu)
* If the user space waits to inject interrupts, exit as soon as
* possible
*/
- if (!irqchip_in_kernel(vcpu->kvm) &&
+ if (!lapic_in_kernel(vcpu) &&
vcpu->run->request_interrupt_window &&
!kvm_cpu_has_interrupt(vcpu)) {
vcpu->run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
@@ -7942,10 +7936,10 @@ static void vmx_set_virtual_x2apic_mode(struct kvm_vcpu *vcpu, bool set)
* apicv
*/
if (!cpu_has_vmx_virtualize_x2apic_mode() ||
- !vmx_vm_has_apicv(vcpu->kvm))
+ !vmx_cpu_uses_apicv(vcpu))
return;
- if (!vm_need_tpr_shadow(vcpu->kvm))
+ if (!cpu_need_tpr_shadow(vcpu))
return;
sec_exec_control = vmcs_read32(SECONDARY_VM_EXEC_CONTROL);
@@ -8050,7 +8044,7 @@ static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)
static void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu)
{
u64 *eoi_exit_bitmap = vcpu->arch.eoi_exit_bitmap;
- if (!vmx_vm_has_apicv(vcpu->kvm))
+ if (!vmx_cpu_uses_apicv(vcpu))
return;
vmcs_write64(EOI_EXIT_BITMAP0, eoi_exit_bitmap[0]);
@@ -8549,7 +8543,7 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id)
put_cpu();
if (err)
goto free_vmcs;
- if (vm_need_virtualize_apic_accesses(kvm)) {
+ if (cpu_need_virtualize_apic_accesses(&vmx->vcpu)) {
err = alloc_apic_access_page(kvm);
if (err)
goto free_vmcs;
@@ -9337,7 +9331,7 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12)
vmcs_write64(APIC_ACCESS_ADDR,
page_to_phys(vmx->nested.apic_access_page));
} else if (!(nested_cpu_has_virt_x2apic_mode(vmcs12)) &&
- (vm_need_virtualize_apic_accesses(vmx->vcpu.kvm))) {
+ cpu_need_virtualize_apic_accesses(&vmx->vcpu)) {
exec_control |=
SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES;
kvm_vcpu_reload_apic_access_page(vcpu);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 394f65aa4e1c..daa6d4fe97fe 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -787,7 +787,7 @@ int kvm_set_cr8(struct kvm_vcpu *vcpu, unsigned long cr8)
{
if (cr8 & CR8_RESERVED_BITS)
return 1;
- if (irqchip_in_kernel(vcpu->kvm))
+ if (lapic_in_kernel(vcpu))
kvm_lapic_set_tpr(vcpu, cr8);
else
vcpu->arch.cr8 = cr8;
@@ -797,7 +797,7 @@ EXPORT_SYMBOL_GPL(kvm_set_cr8);
unsigned long kvm_get_cr8(struct kvm_vcpu *vcpu)
{
- if (irqchip_in_kernel(vcpu->kvm))
+ if (lapic_in_kernel(vcpu))
return kvm_lapic_get_cr8(vcpu);
else
return vcpu->arch.cr8;
@@ -3188,7 +3188,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
struct kvm_vapic_addr va;
r = -EINVAL;
- if (!irqchip_in_kernel(vcpu->kvm))
+ if (!lapic_in_kernel(vcpu))
goto out;
r = -EFAULT;
if (copy_from_user(&va, argp, sizeof va))
@@ -5679,7 +5679,7 @@ void kvm_arch_exit(void)
int kvm_vcpu_halt(struct kvm_vcpu *vcpu)
{
++vcpu->stat.halt_exits;
- if (irqchip_in_kernel(vcpu->kvm)) {
+ if (lapic_in_kernel(vcpu)) {
vcpu->arch.mp_state = KVM_MP_STATE_HALTED;
return 1;
} else {
@@ -6168,7 +6168,7 @@ void kvm_vcpu_reload_apic_access_page(struct kvm_vcpu *vcpu)
{
struct page *page = NULL;
- if (!irqchip_in_kernel(vcpu->kvm))
+ if (!lapic_in_kernel(vcpu))
return;
if (!kvm_x86_ops->set_apic_access_page_addr)
@@ -6206,7 +6206,7 @@ void kvm_arch_mmu_notifier_invalidate_page(struct kvm *kvm,
static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
{
int r;
- bool req_int_win = !irqchip_in_kernel(vcpu->kvm) &&
+ bool req_int_win = !lapic_in_kernel(vcpu) &&
vcpu->run->request_interrupt_window;
bool req_immediate_exit = false;
@@ -6603,7 +6603,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
}
/* re-sync apic's tpr */
- if (!irqchip_in_kernel(vcpu->kvm)) {
+ if (!lapic_in_kernel(vcpu)) {
if (kvm_set_cr8(vcpu, kvm_run->cr8) != 0) {
r = -EINVAL;
goto out;
@@ -7303,7 +7303,7 @@ bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu)
bool kvm_vcpu_compatible(struct kvm_vcpu *vcpu)
{
- return irqchip_in_kernel(vcpu->kvm) == (vcpu->arch.apic != NULL);
+ return irqchip_in_kernel(vcpu->kvm) == lapic_in_kernel(vcpu);
}
struct static_key kvm_no_apic_vcpu __read_mostly;
@@ -7397,7 +7397,7 @@ void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
kvm_mmu_destroy(vcpu);
srcu_read_unlock(&vcpu->kvm->srcu, idx);
free_page((unsigned long)vcpu->arch.pio_data);
- if (!irqchip_in_kernel(vcpu->kvm))
+ if (!lapic_in_kernel(vcpu))
static_key_slow_dec(&kvm_no_apic_vcpu);
}
--
1.8.3.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 5/9] KVM: x86: unify handling of interrupt window
2015-08-05 15:23 [PATCH 0/9] split irqchip series Paolo Bonzini
` (3 preceding siblings ...)
2015-08-05 15:23 ` [PATCH 4/9] KVM: x86: introduce lapic_in_kernel Paolo Bonzini
@ 2015-08-05 15:23 ` Paolo Bonzini
2015-08-06 6:50 ` Wu, Feng
2015-08-05 15:23 ` [PATCH 6/9] KVM: x86: Split the APIC from the rest of IRQCHIP Paolo Bonzini
` (3 subsequent siblings)
8 siblings, 1 reply; 17+ messages in thread
From: Paolo Bonzini @ 2015-08-05 15:23 UTC (permalink / raw)
To: linux-kernel, kvm; +Cc: Steve Rutherford, rkrcmar
The interrupt window is currently checked twice, once in vmx.c/svm.c and
once in dm_request_for_irq_injection. The only difference is the extra
check for kvm_arch_interrupt_allowed in dm_request_for_irq_injection,
and the different return value (EINTR/KVM_EXIT_INTR for vmx.c/svm.c vs.
0/KVM_EXIT_IRQ_WINDOW_OPEN for dm_request_for_irq_injection).
However, dm_request_for_irq_injection is basically dead code! Revive it
by removing the checks in vmx.c and svm.c's vmexit handlers, and
fixing the returned values for the dm_request_for_irq_injection case.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/svm.c | 13 -------------
arch/x86/kvm/vmx.c | 11 -----------
arch/x86/kvm/x86.c | 4 ++--
3 files changed, 2 insertions(+), 26 deletions(-)
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 222439fd73d4..189e46479dd5 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -3396,24 +3396,11 @@ static int msr_interception(struct vcpu_svm *svm)
static int interrupt_window_interception(struct vcpu_svm *svm)
{
- struct kvm_run *kvm_run = svm->vcpu.run;
-
kvm_make_request(KVM_REQ_EVENT, &svm->vcpu);
svm_clear_vintr(svm);
svm->vmcb->control.int_ctl &= ~V_IRQ_MASK;
mark_dirty(svm->vmcb, VMCB_INTR);
++svm->vcpu.stat.irq_window_exits;
- /*
- * If the user space waits to inject interrupts, exit as soon as
- * possible
- */
- if (!lapic_in_kernel(&svm->vcpu) &&
- kvm_run->request_interrupt_window &&
- !kvm_cpu_has_interrupt(&svm->vcpu)) {
- kvm_run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
- return 0;
- }
-
return 1;
}
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index ef15dc72284b..4cf25b90dbe0 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -5524,17 +5524,6 @@ static int handle_interrupt_window(struct kvm_vcpu *vcpu)
kvm_make_request(KVM_REQ_EVENT, vcpu);
++vcpu->stat.irq_window_exits;
-
- /*
- * If the user space waits to inject interrupts, exit as soon as
- * possible
- */
- if (!lapic_in_kernel(vcpu) &&
- vcpu->run->request_interrupt_window &&
- !kvm_cpu_has_interrupt(vcpu)) {
- vcpu->run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
- return 0;
- }
return 1;
}
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index daa6d4fe97fe..62362fed4169 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6475,8 +6475,8 @@ static int vcpu_run(struct kvm_vcpu *vcpu)
kvm_inject_pending_timer_irqs(vcpu);
if (dm_request_for_irq_injection(vcpu)) {
- r = -EINTR;
- vcpu->run->exit_reason = KVM_EXIT_INTR;
+ r = 0;
+ vcpu->run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
++vcpu->stat.request_irq_exits;
break;
}
--
1.8.3.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* RE: [PATCH 5/9] KVM: x86: unify handling of interrupt window
2015-08-05 15:23 ` [PATCH 5/9] KVM: x86: unify handling of interrupt window Paolo Bonzini
@ 2015-08-06 6:50 ` Wu, Feng
2015-08-06 11:55 ` Paolo Bonzini
0 siblings, 1 reply; 17+ messages in thread
From: Wu, Feng @ 2015-08-06 6:50 UTC (permalink / raw)
To: Paolo Bonzini, linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Steve Rutherford, rkrcmar@redhat.com, Wu, Feng
> -----Original Message-----
> From: linux-kernel-owner@vger.kernel.org
> [mailto:linux-kernel-owner@vger.kernel.org] On Behalf Of Paolo Bonzini
> Sent: Wednesday, August 05, 2015 11:24 PM
> To: linux-kernel@vger.kernel.org; kvm@vger.kernel.org
> Cc: Steve Rutherford; rkrcmar@redhat.com
> Subject: [PATCH 5/9] KVM: x86: unify handling of interrupt window
>
> The interrupt window is currently checked twice, once in vmx.c/svm.c and
> once in dm_request_for_irq_injection. The only difference is the extra
> check for kvm_arch_interrupt_allowed in dm_request_for_irq_injection,
> and the different return value (EINTR/KVM_EXIT_INTR for vmx.c/svm.c vs.
> 0/KVM_EXIT_IRQ_WINDOW_OPEN for dm_request_for_irq_injection).
>
> However, dm_request_for_irq_injection is basically dead code! Revive it
> by removing the checks in vmx.c and svm.c's vmexit handlers, and
> fixing the returned values for the dm_request_for_irq_injection case.
>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
> arch/x86/kvm/svm.c | 13 -------------
> arch/x86/kvm/vmx.c | 11 -----------
> arch/x86/kvm/x86.c | 4 ++--
> 3 files changed, 2 insertions(+), 26 deletions(-)
>
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index 222439fd73d4..189e46479dd5 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -3396,24 +3396,11 @@ static int msr_interception(struct vcpu_svm
> *svm)
>
> static int interrupt_window_interception(struct vcpu_svm *svm)
> {
> - struct kvm_run *kvm_run = svm->vcpu.run;
> -
> kvm_make_request(KVM_REQ_EVENT, &svm->vcpu);
> svm_clear_vintr(svm);
> svm->vmcb->control.int_ctl &= ~V_IRQ_MASK;
> mark_dirty(svm->vmcb, VMCB_INTR);
> ++svm->vcpu.stat.irq_window_exits;
> - /*
> - * If the user space waits to inject interrupts, exit as soon as
> - * possible
> - */
> - if (!lapic_in_kernel(&svm->vcpu) &&
> - kvm_run->request_interrupt_window &&
> - !kvm_cpu_has_interrupt(&svm->vcpu)) {
> - kvm_run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
> - return 0;
> - }
> -
> return 1;
> }
>
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index ef15dc72284b..4cf25b90dbe0 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -5524,17 +5524,6 @@ static int handle_interrupt_window(struct
> kvm_vcpu *vcpu)
> kvm_make_request(KVM_REQ_EVENT, vcpu);
>
> ++vcpu->stat.irq_window_exits;
> -
> - /*
> - * If the user space waits to inject interrupts, exit as soon as
> - * possible
> - */
> - if (!lapic_in_kernel(vcpu) &&
> - vcpu->run->request_interrupt_window &&
> - !kvm_cpu_has_interrupt(vcpu)) {
> - vcpu->run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
> - return 0;
> - }
> return 1;
> }
Is it possible to adjust the code here and remove the later checking in x86.c?
In that case, we can avoid calling dm_request_for_irq_injection(vcpu) for
VM exit. Basically dm_request_for_irq_injection() did the following
checks:
- The same as in handle_interrupt_window() below:
if (!irqchip_in_kernel(vcpu->kvm) &&
vcpu->run->request_interrupt_window &&
!kvm_cpu_has_interrupt(vcpu))
- kvm_arch_interrupt_allowed(vcpu), in which, most of the conditions
are guaranteed by interrupt window exits, the only one I am not sure
how to handle is ' to_vmx(vcpu)->nested.nested_run_pending'.
Thanks,
Feng
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index daa6d4fe97fe..62362fed4169 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -6475,8 +6475,8 @@ static int vcpu_run(struct kvm_vcpu *vcpu)
> kvm_inject_pending_timer_irqs(vcpu);
>
> if (dm_request_for_irq_injection(vcpu)) {
> - r = -EINTR;
> - vcpu->run->exit_reason = KVM_EXIT_INTR;
> + r = 0;
> + vcpu->run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
> ++vcpu->stat.request_irq_exits;
> break;
> }
> --
> 1.8.3.1
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
^ permalink raw reply [flat|nested] 17+ messages in thread* Re: [PATCH 5/9] KVM: x86: unify handling of interrupt window
2015-08-06 6:50 ` Wu, Feng
@ 2015-08-06 11:55 ` Paolo Bonzini
0 siblings, 0 replies; 17+ messages in thread
From: Paolo Bonzini @ 2015-08-06 11:55 UTC (permalink / raw)
To: Wu, Feng, linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Steve Rutherford, rkrcmar@redhat.com
On 06/08/2015 08:50, Wu, Feng wrote:
> Is it possible to adjust the code here and remove the later checking in x86.c?
> In that case, we can avoid calling dm_request_for_irq_injection(vcpu) for
> VM exit.
No, see the dm_request_for_irq_injection() changes in patch 9. In that
patch, you can get a IRQ window open vmexit under broader conditions
(e.g. writing to the local APIC's LVT0 register).
dm_request_for_irq_injection() is called just once, so it is inlined.
After patch 9, it boils down to simply
if (!vcpu->run->request_interrupt_window)
return false;
in the common case of in-kernel irqchip. So it costs just one memory
access and a well-predicted branch.
Paolo
> Basically dm_request_for_irq_injection() did the following checks:
>
> - The same as in handle_interrupt_window() below:
>
> if (!irqchip_in_kernel(vcpu->kvm) &&
> vcpu->run->request_interrupt_window &&
> !kvm_cpu_has_interrupt(vcpu))
>
> - kvm_arch_interrupt_allowed(vcpu), in which, most of the conditions
> are guaranteed by interrupt window exits, the only one I am not sure
> how to handle is ' to_vmx(vcpu)->nested.nested_run_pending'.
^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 6/9] KVM: x86: Split the APIC from the rest of IRQCHIP.
2015-08-05 15:23 [PATCH 0/9] split irqchip series Paolo Bonzini
` (4 preceding siblings ...)
2015-08-05 15:23 ` [PATCH 5/9] KVM: x86: unify handling of interrupt window Paolo Bonzini
@ 2015-08-05 15:23 ` Paolo Bonzini
2015-08-05 15:23 ` [PATCH 7/9] KVM: x86: Add KVM exit for IOAPIC EOIs Paolo Bonzini
` (2 subsequent siblings)
8 siblings, 0 replies; 17+ messages in thread
From: Paolo Bonzini @ 2015-08-05 15:23 UTC (permalink / raw)
To: linux-kernel, kvm; +Cc: Steve Rutherford, rkrcmar
From: Steve Rutherford <srutherford@google.com>
First patch in a series which enables the relocation of the
PIC/IOAPIC to userspace.
Adds capability KVM_CAP_SPLIT_IRQCHIP;
KVM_CAP_SPLIT_IRQCHIP enables the construction of LAPICs without the
rest of the irqchip.
Compile tested for x86.
Signed-off-by: Steve Rutherford <srutherford@google.com>
Suggested-by: Andrew Honig <ahonig@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
Documentation/virtual/kvm/api.txt | 17 +++++++++++++++++
arch/x86/include/asm/kvm_host.h | 2 ++
arch/x86/kvm/i8254.c | 4 +++-
arch/x86/kvm/ioapic.h | 8 ++++++++
arch/x86/kvm/irq.h | 11 ++++++++++-
arch/x86/kvm/irq_comm.c | 9 ++++++++-
arch/x86/kvm/lapic.c | 6 ++++--
arch/x86/kvm/x86.c | 23 +++++++++++++++++++++--
include/linux/kvm_host.h | 1 +
include/uapi/linux/kvm.h | 1 +
10 files changed, 75 insertions(+), 7 deletions(-)
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index a4ebcb712375..c807c8391af1 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -3620,6 +3620,23 @@ struct {
KVM handlers should exit to userspace with rc = -EREMOTE.
+7.5 KVM_CAP_SPLIT_IRQCHIP
+
+Architectures: x86
+Parameters: None
+Returns: 0 on success, -1 on error
+
+Create a local apic for each processor in the kernel. This can be used
+instead of KVM_CREATE_IRQCHIP if the userspace VMM wishes to emulate the
+IOAPIC and PIC (and also the PIT, even though this has to be enabled
+separately).
+
+This supersedes KVM_CREATE_IRQCHIP, creating only local APICs, but no in kernel
+IOAPIC or PIC. This also enables in kernel routing of interrupt requests.
+
+Fails if VCPU has already been created, or if the irqchip is already in the
+kernel (i.e. KVM_CREATE_IRQCHIP has already been called).
+
8. Other capabilities.
----------------------
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index deeb98617e22..15be76340acc 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -683,6 +683,8 @@ struct kvm_arch {
u32 bsp_vcpu_id;
u64 disabled_quirks;
+
+ bool irqchip_split;
};
struct kvm_vm_stat {
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index f90952f64e79..08116ff227cc 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -35,6 +35,7 @@
#include <linux/kvm_host.h>
#include <linux/slab.h>
+#include "ioapic.h"
#include "irq.h"
#include "i8254.h"
#include "x86.h"
@@ -333,7 +334,8 @@ static void create_pit_timer(struct kvm *kvm, u32 val, int is_period)
struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state;
s64 interval;
- if (!irqchip_in_kernel(kvm) || ps->flags & KVM_PIT_FLAGS_HPET_LEGACY)
+ if (!ioapic_in_kernel(kvm) ||
+ ps->flags & KVM_PIT_FLAGS_HPET_LEGACY)
return;
interval = muldiv64(val, NSEC_PER_SEC, KVM_PIT_FREQ);
diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h
index bf36d66a1951..a8842c0dee73 100644
--- a/arch/x86/kvm/ioapic.h
+++ b/arch/x86/kvm/ioapic.h
@@ -97,6 +97,14 @@ static inline struct kvm_ioapic *ioapic_irqchip(struct kvm *kvm)
return kvm->arch.vioapic;
}
+static inline int ioapic_in_kernel(struct kvm *kvm)
+{
+ int ret;
+
+ ret = (ioapic_irqchip(kvm) != NULL);
+ return ret;
+}
+
void kvm_rtc_eoi_tracking_restore_one(struct kvm_vcpu *vcpu);
bool kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
int short_hand, unsigned int dest, int dest_mode);
diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index 9e6e7e04de98..2f9703dcd913 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -83,13 +83,22 @@ static inline struct kvm_pic *pic_irqchip(struct kvm *kvm)
return kvm->arch.vpic;
}
+static inline int irqchip_split(struct kvm *kvm)
+{
+ return kvm->arch.irqchip_split;
+}
+
static inline int irqchip_in_kernel(struct kvm *kvm)
{
struct kvm_pic *vpic = pic_irqchip(kvm);
+ bool ret;
+
+ ret = (vpic != NULL);
+ ret |= irqchip_split(kvm);
/* Read vpic before kvm->irq_routing. */
smp_rmb();
- return vpic != NULL;
+ return ret;
}
static inline int lapic_in_kernel(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index 9efff9e5b58c..67f6b62a6814 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -208,7 +208,7 @@ void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
goto unlock;
}
clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
- if (!irqchip_in_kernel(kvm))
+ if (!ioapic_in_kernel(kvm))
goto unlock;
kvm_ioapic_clear_all(kvm->arch.vioapic, irq_source_id);
@@ -328,3 +328,10 @@ int kvm_setup_default_irq_routing(struct kvm *kvm)
return kvm_set_irq_routing(kvm, default_routing,
ARRAY_SIZE(default_routing), 0);
}
+
+static const struct kvm_irq_routing_entry empty_routing[] = {};
+
+int kvm_setup_empty_irq_routing(struct kvm *kvm)
+{
+ return kvm_set_irq_routing(kvm, empty_routing, 0, 0);
+}
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 5cae917451f9..24b53f453396 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -209,7 +209,8 @@ out:
if (old)
kfree_rcu(old, rcu);
- kvm_vcpu_request_scan_ioapic(kvm);
+ if (ioapic_in_kernel(kvm))
+ kvm_vcpu_request_scan_ioapic(kvm);
}
static inline void apic_set_spiv(struct kvm_lapic *apic, u32 val)
@@ -1845,7 +1846,8 @@ void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu,
kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
apic_find_highest_isr(apic));
kvm_make_request(KVM_REQ_EVENT, vcpu);
- kvm_rtc_eoi_tracking_restore_one(vcpu);
+ if (ioapic_in_kernel(vcpu->kvm))
+ kvm_rtc_eoi_tracking_restore_one(vcpu);
}
void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 62362fed4169..ff1a39d4401f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2461,6 +2461,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
case KVM_CAP_ENABLE_CAP_VM:
case KVM_CAP_DISABLE_QUIRKS:
case KVM_CAP_SET_BOOT_CPU_ID:
+ case KVM_CAP_SPLIT_IRQCHIP:
#ifdef CONFIG_KVM_DEVICE_ASSIGNMENT
case KVM_CAP_ASSIGN_DEV_IRQ:
case KVM_CAP_PCI_2_3:
@@ -3568,6 +3569,24 @@ static int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
kvm->arch.disabled_quirks = cap->args[0];
r = 0;
break;
+ case KVM_CAP_SPLIT_IRQCHIP: {
+ mutex_lock(&kvm->lock);
+ r = -EEXIST;
+ if (irqchip_in_kernel(kvm))
+ goto split_irqchip_unlock;
+ if (atomic_read(&kvm->online_vcpus))
+ goto split_irqchip_unlock;
+ r = kvm_setup_empty_irq_routing(kvm);
+ if (r)
+ goto split_irqchip_unlock;
+ /* Pairs with irqchip_in_kernel. */
+ smp_wmb();
+ kvm->arch.irqchip_split = true;
+ r = 0;
+split_irqchip_unlock:
+ mutex_unlock(&kvm->lock);
+ break;
+ }
default:
r = -EINVAL;
break;
@@ -3681,7 +3700,7 @@ long kvm_arch_vm_ioctl(struct file *filp,
}
r = -ENXIO;
- if (!irqchip_in_kernel(kvm))
+ if (!irqchip_in_kernel(kvm) || irqchip_split(kvm))
goto get_irqchip_out;
r = kvm_vm_ioctl_get_irqchip(kvm, chip);
if (r)
@@ -3705,7 +3724,7 @@ long kvm_arch_vm_ioctl(struct file *filp,
}
r = -ENXIO;
- if (!irqchip_in_kernel(kvm))
+ if (!irqchip_in_kernel(kvm) || irqchip_split(kvm))
goto set_irqchip_out;
r = kvm_vm_ioctl_set_irqchip(kvm, chip);
if (r)
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 81089cf1f0c1..e9bd0e4c06ea 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1001,6 +1001,7 @@ static inline int mmu_notifier_retry(struct kvm *kvm, unsigned long mmu_seq)
#endif
int kvm_setup_default_irq_routing(struct kvm *kvm);
+int kvm_setup_empty_irq_routing(struct kvm *kvm);
int kvm_set_irq_routing(struct kvm *kvm,
const struct kvm_irq_routing_entry *entries,
unsigned nr,
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 0d831f94f8a8..cee1c18f8a5d 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -819,6 +819,7 @@ struct kvm_ppc_smmu_info {
#define KVM_CAP_DISABLE_QUIRKS 116
#define KVM_CAP_X86_SMM 117
#define KVM_CAP_MULTI_ADDRESS_SPACE 118
+#define KVM_CAP_SPLIT_IRQCHIP 119
#ifdef KVM_CAP_IRQ_ROUTING
--
1.8.3.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 7/9] KVM: x86: Add KVM exit for IOAPIC EOIs
2015-08-05 15:23 [PATCH 0/9] split irqchip series Paolo Bonzini
` (5 preceding siblings ...)
2015-08-05 15:23 ` [PATCH 6/9] KVM: x86: Split the APIC from the rest of IRQCHIP Paolo Bonzini
@ 2015-08-05 15:23 ` Paolo Bonzini
2015-08-05 15:23 ` [PATCH 8/9] KVM: x86: Add EOI exit bitmap inference Paolo Bonzini
2015-08-05 15:23 ` [PATCH 9/9] KVM: x86: Add support for local interrupt requests from userspace Paolo Bonzini
8 siblings, 0 replies; 17+ messages in thread
From: Paolo Bonzini @ 2015-08-05 15:23 UTC (permalink / raw)
To: linux-kernel, kvm; +Cc: Steve Rutherford, rkrcmar
From: Steve Rutherford <srutherford@google.com>
Adds KVM_EXIT_IOAPIC_EOI which allows the kernel to EOI
level-triggered IOAPIC interrupts.
Uses a per VCPU exit bitmap to decide whether or not the IOAPIC needs
to be informed (which is identical to the EOI_EXIT_BITMAP field used
by modern x86 processors, but can also be used to elide kvm IOAPIC EOI
exits on older processors).
[Note: A prototype using ResampleFDs found that decoupling the EOI
from the VCPU's thread made it possible for the VCPU to not see a
recent EOI after reentering the guest. This does not match real
hardware.]
Compile tested for Intel x86.
Signed-off-by: Steve Rutherford <srutherford@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
Documentation/virtual/kvm/api.txt | 12 ++++++++++++
arch/x86/include/asm/kvm_host.h | 2 ++
arch/x86/kvm/lapic.c | 24 +++++++++++++++++-------
arch/x86/kvm/x86.c | 11 +++++++++++
include/linux/kvm_host.h | 2 +-
include/uapi/linux/kvm.h | 5 +++++
6 files changed, 48 insertions(+), 8 deletions(-)
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index c807c8391af1..bda6cb747b23 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -3302,6 +3302,18 @@ Valid values for 'type' are:
to ignore the request, or to gather VM memory core dump and/or
reset/shutdown of the VM.
+ /* KVM_EXIT_IOAPIC_EOI */
+ struct {
+ __u8 vector;
+ } eoi;
+
+Indicates that the VCPU's in-kernel local APIC received an EOI for a
+level-triggered IOAPIC interrupt. This exit only triggers when the
+IOAPIC is implemented in userspace (i.e. KVM_CAP_SPLIT_IRQCHIP is enabled);
+the userspace IOAPIC should process the EOI and retrigger the interrupt if
+it is still asserted. Vector is the LAPIC interrupt vector for which the
+EOI was received.
+
/* Fix the size of the union. */
char padding[256];
};
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 15be76340acc..4294722dfd1d 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -573,6 +573,8 @@ struct kvm_vcpu_arch {
struct {
bool pv_unhalted;
} pv;
+
+ int pending_ioapic_eoi;
};
struct kvm_lpage_info {
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 24b53f453396..14b5603ef6c5 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -877,15 +877,25 @@ static bool kvm_ioapic_handles_vector(struct kvm_lapic *apic, int vector)
static void kvm_ioapic_send_eoi(struct kvm_lapic *apic, int vector)
{
- if (kvm_ioapic_handles_vector(apic, vector)) {
- int trigger_mode;
- if (apic_test_vector(vector, apic->regs + APIC_TMR))
- trigger_mode = IOAPIC_LEVEL_TRIG;
- else
- trigger_mode = IOAPIC_EDGE_TRIG;
+ int trigger_mode;
+
+ /* Eoi the ioapic only if the ioapic doesn't own the vector. */
+ if (!kvm_ioapic_handles_vector(apic, vector))
+ return;
- kvm_ioapic_update_eoi(apic->vcpu, vector, trigger_mode);
+ /* Request a KVM exit to inform the userspace IOAPIC. */
+ if (irqchip_split(apic->vcpu->kvm)) {
+ apic->vcpu->arch.pending_ioapic_eoi = vector;
+ kvm_make_request(KVM_REQ_IOAPIC_EOI_EXIT, apic->vcpu);
+ return;
}
+
+ if (apic_test_vector(vector, apic->regs + APIC_TMR))
+ trigger_mode = IOAPIC_LEVEL_TRIG;
+ else
+ trigger_mode = IOAPIC_EDGE_TRIG;
+
+ kvm_ioapic_update_eoi(apic->vcpu, vector, trigger_mode);
}
static int apic_set_eoi(struct kvm_lapic *apic)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index ff1a39d4401f..16e2f3c577c7 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6277,6 +6277,17 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
kvm_pmu_handle_event(vcpu);
if (kvm_check_request(KVM_REQ_PMI, vcpu))
kvm_pmu_deliver_pmi(vcpu);
+ if (kvm_check_request(KVM_REQ_IOAPIC_EOI_EXIT, vcpu)) {
+ BUG_ON(vcpu->arch.pending_ioapic_eoi > 255);
+ if (test_bit(vcpu->arch.pending_ioapic_eoi,
+ (void *) vcpu->arch.eoi_exit_bitmap)) {
+ vcpu->run->exit_reason = KVM_EXIT_IOAPIC_EOI;
+ vcpu->run->eoi.vector =
+ vcpu->arch.pending_ioapic_eoi;
+ r = 0;
+ goto out;
+ }
+ }
if (kvm_check_request(KVM_REQ_SCAN_IOAPIC, vcpu))
vcpu_scan_ioapic(vcpu);
if (kvm_check_request(KVM_REQ_APIC_PAGE_RELOAD, vcpu))
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index e9bd0e4c06ea..653d494e13d1 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -140,6 +140,7 @@ static inline bool is_error_page(struct page *page)
#define KVM_REQ_APIC_PAGE_RELOAD 25
#define KVM_REQ_SMI 26
#define KVM_REQ_HV_CRASH 27
+#define KVM_REQ_IOAPIC_EOI_EXIT 28
#define KVM_USERSPACE_IRQ_SOURCE_ID 0
#define KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID 1
@@ -1145,4 +1146,3 @@ static inline void kvm_vcpu_set_dy_eligible(struct kvm_vcpu *vcpu, bool val)
}
#endif /* CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT */
#endif
-
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index cee1c18f8a5d..26daafbba9ec 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -183,6 +183,7 @@ struct kvm_s390_skeys {
#define KVM_EXIT_EPR 23
#define KVM_EXIT_SYSTEM_EVENT 24
#define KVM_EXIT_S390_STSI 25
+#define KVM_EXIT_IOAPIC_EOI 26
/* For KVM_EXIT_INTERNAL_ERROR */
/* Emulate instruction failed. */
@@ -330,6 +331,10 @@ struct kvm_run {
__u8 sel1;
__u16 sel2;
} s390_stsi;
+ /* KVM_EXIT_IOAPIC_EOI */
+ struct {
+ __u8 vector;
+ } eoi;
/* Fix the size of the union. */
char padding[256];
};
--
1.8.3.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH 8/9] KVM: x86: Add EOI exit bitmap inference
2015-08-05 15:23 [PATCH 0/9] split irqchip series Paolo Bonzini
` (6 preceding siblings ...)
2015-08-05 15:23 ` [PATCH 7/9] KVM: x86: Add KVM exit for IOAPIC EOIs Paolo Bonzini
@ 2015-08-05 15:23 ` Paolo Bonzini
2015-08-07 5:43 ` Wu, Feng
2015-08-07 7:46 ` Wu, Feng
2015-08-05 15:23 ` [PATCH 9/9] KVM: x86: Add support for local interrupt requests from userspace Paolo Bonzini
8 siblings, 2 replies; 17+ messages in thread
From: Paolo Bonzini @ 2015-08-05 15:23 UTC (permalink / raw)
To: linux-kernel, kvm; +Cc: Steve Rutherford, rkrcmar
From: Steve Rutherford <srutherford@google.com>
In order to support a userspace IOAPIC interacting with an in kernel
APIC, the EOI exit bitmaps need to be configurable.
If the IOAPIC is in userspace (i.e. the irqchip has been split), the
EOI exit bitmaps will be set whenever the GSI Routes are configured.
In particular, for the low MSI routes are reservable for userspace
IOAPICs. For these MSI routes, the EOI Exit bit corresponding to the
destination vector of the route will be set for the destination VCPU.
The intention is for the userspace IOAPICs to use the reservable MSI
routes to inject interrupts into the guest.
This is a slight abuse of the notion of an MSI Route, given that MSIs
classically bypass the IOAPIC. It might be worthwhile to add an
additional route type to improve clarity.
Compile tested for Intel x86.
Signed-off-by: Steve Rutherford <srutherford@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
Documentation/virtual/kvm/api.txt | 9 ++++++---
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/ioapic.h | 2 ++
arch/x86/kvm/irq_comm.c | 42 +++++++++++++++++++++++++++++++++++++++
arch/x86/kvm/lapic.c | 3 +--
arch/x86/kvm/x86.c | 9 ++++++++-
include/linux/kvm_host.h | 17 ++++++++++++++++
virt/kvm/irqchip.c | 12 ++---------
8 files changed, 79 insertions(+), 16 deletions(-)
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index bda6cb747b23..dcd748e2d46d 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -3635,7 +3635,7 @@ KVM handlers should exit to userspace with rc = -EREMOTE.
7.5 KVM_CAP_SPLIT_IRQCHIP
Architectures: x86
-Parameters: None
+Parameters: args[0] - number of routes reserved for userspace IOAPICs
Returns: 0 on success, -1 on error
Create a local apic for each processor in the kernel. This can be used
@@ -3643,8 +3643,11 @@ instead of KVM_CREATE_IRQCHIP if the userspace VMM wishes to emulate the
IOAPIC and PIC (and also the PIT, even though this has to be enabled
separately).
-This supersedes KVM_CREATE_IRQCHIP, creating only local APICs, but no in kernel
-IOAPIC or PIC. This also enables in kernel routing of interrupt requests.
+This capability also enables in kernel routing of interrupt requests;
+when KVM_CAP_SPLIT_IRQCHIP only routes of KVM_IRQ_ROUTING_MSI type are
+used in the IRQ routing table. The first args[0] MSI routes are reserved
+for the IOAPIC pins. Whenever the LAPIC receives an EOI for these routes,
+a KVM_EXIT_IOAPIC_EOI vmexit will be reported to userspace.
Fails if VCPU has already been created, or if the irqchip is already in the
kernel (i.e. KVM_CREATE_IRQCHIP has already been called).
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 4294722dfd1d..4bc714f7b164 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -687,6 +687,7 @@ struct kvm_arch {
u64 disabled_quirks;
bool irqchip_split;
+ u8 nr_reserved_ioapic_pins;
};
struct kvm_vm_stat {
diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h
index a8842c0dee73..084617d37c74 100644
--- a/arch/x86/kvm/ioapic.h
+++ b/arch/x86/kvm/ioapic.h
@@ -9,6 +9,7 @@ struct kvm;
struct kvm_vcpu;
#define IOAPIC_NUM_PINS KVM_IOAPIC_NUM_PINS
+#define MAX_NR_RESERVED_IOAPIC_PINS KVM_MAX_IRQ_ROUTES
#define IOAPIC_VERSION_ID 0x11 /* IOAPIC version */
#define IOAPIC_EDGE_TRIG 0
#define IOAPIC_LEVEL_TRIG 1
@@ -121,5 +122,6 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
+void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
#endif
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
index 67f6b62a6814..177460998bb0 100644
--- a/arch/x86/kvm/irq_comm.c
+++ b/arch/x86/kvm/irq_comm.c
@@ -335,3 +335,45 @@ int kvm_setup_empty_irq_routing(struct kvm *kvm)
{
return kvm_set_irq_routing(kvm, empty_routing, 0, 0);
}
+
+void kvm_arch_irq_routing_update(struct kvm *kvm)
+{
+ if (ioapic_in_kernel(kvm) || !irqchip_in_kernel(kvm))
+ return;
+ kvm_make_scan_ioapic_request(kvm);
+}
+
+void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
+{
+ struct kvm *kvm = vcpu->kvm;
+ struct kvm_kernel_irq_routing_entry *entry;
+ struct kvm_irq_routing_table *table;
+ u32 i, nr_ioapic_pins;
+ int idx;
+
+ /* kvm->irq_routing must be read after clearing
+ * KVM_SCAN_IOAPIC. */
+ smp_mb();
+ idx = srcu_read_lock(&kvm->irq_srcu);
+ table = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
+ nr_ioapic_pins = min_t(u32, table->nr_rt_entries,
+ kvm->arch.nr_reserved_ioapic_pins);
+ for (i = 0; i < nr_ioapic_pins; ++i) {
+ hlist_for_each_entry(entry, &table->map[i], link) {
+ u32 dest_id, dest_mode;
+
+ if (entry->type != KVM_IRQ_ROUTING_MSI)
+ continue;
+ dest_id = (entry->msi.address_lo >> 12) & 0xff;
+ dest_mode = (entry->msi.address_lo >> 2) & 0x1;
+ if (kvm_apic_match_dest(vcpu, NULL, 0, dest_id,
+ dest_mode)) {
+ u32 vector = entry->msi.data & 0xff;
+
+ __set_bit(vector,
+ (unsigned long *) eoi_exit_bitmap);
+ }
+ }
+ }
+ srcu_read_unlock(&kvm->irq_srcu, idx);
+}
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 14b5603ef6c5..38c580aa27c2 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -209,8 +209,7 @@ out:
if (old)
kfree_rcu(old, rcu);
- if (ioapic_in_kernel(kvm))
- kvm_vcpu_request_scan_ioapic(kvm);
+ kvm_make_scan_ioapic_request(kvm);
}
static inline void apic_set_spiv(struct kvm_lapic *apic, u32 val)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 16e2f3c577c7..c9fb11491aa3 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3571,6 +3571,9 @@ static int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
break;
case KVM_CAP_SPLIT_IRQCHIP: {
mutex_lock(&kvm->lock);
+ r = -EINVAL;
+ if (cap->args[0] > MAX_NR_RESERVED_IOAPIC_PINS)
+ goto split_irqchip_unlock;
r = -EEXIST;
if (irqchip_in_kernel(kvm))
goto split_irqchip_unlock;
@@ -3582,6 +3585,7 @@ static int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
/* Pairs with irqchip_in_kernel. */
smp_wmb();
kvm->arch.irqchip_split = true;
+ kvm->arch.nr_reserved_ioapic_pins = cap->args[0];
r = 0;
split_irqchip_unlock:
mutex_unlock(&kvm->lock);
@@ -6173,7 +6177,10 @@ static void vcpu_scan_ioapic(struct kvm_vcpu *vcpu)
memset(vcpu->arch.eoi_exit_bitmap, 0, 256 / 8);
- kvm_ioapic_scan_entry(vcpu, vcpu->arch.eoi_exit_bitmap);
+ if (irqchip_split(vcpu->kvm))
+ kvm_scan_ioapic_routes(vcpu, vcpu->arch.eoi_exit_bitmap);
+ else
+ kvm_ioapic_scan_entry(vcpu, vcpu->arch.eoi_exit_bitmap);
kvm_x86_ops->load_eoi_exitmap(vcpu);
}
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 653d494e13d1..27ccdf91a465 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -329,6 +329,19 @@ struct kvm_kernel_irq_routing_entry {
struct hlist_node link;
};
+#ifdef CONFIG_HAVE_KVM_IRQCHIP
+struct kvm_irq_routing_table {
+ int chip[KVM_NR_IRQCHIPS][KVM_IRQCHIP_NUM_PINS];
+ struct kvm_kernel_irq_routing_entry *rt_entries;
+ u32 nr_rt_entries;
+ /*
+ * Array indexed by gsi. Each entry contains list of irq chips
+ * the gsi is connected to.
+ */
+ struct hlist_head map[0];
+};
+#endif
+
#ifndef KVM_PRIVATE_MEM_SLOTS
#define KVM_PRIVATE_MEM_SLOTS 0
#endif
@@ -455,10 +468,14 @@ void vcpu_put(struct kvm_vcpu *vcpu);
#ifdef __KVM_HAVE_IOAPIC
void kvm_vcpu_request_scan_ioapic(struct kvm *kvm);
+void kvm_arch_irq_routing_update(struct kvm *kvm);
#else
static inline void kvm_vcpu_request_scan_ioapic(struct kvm *kvm)
{
}
+static inline void kvm_arch_irq_routing_update(struct kvm *kvm)
+{
+}
#endif
#ifdef CONFIG_HAVE_KVM_IRQFD
diff --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c
index 21c14244f4c4..4f85c6ee96dc 100644
--- a/virt/kvm/irqchip.c
+++ b/virt/kvm/irqchip.c
@@ -31,16 +31,6 @@
#include <trace/events/kvm.h>
#include "irq.h"
-struct kvm_irq_routing_table {
- int chip[KVM_NR_IRQCHIPS][KVM_IRQCHIP_NUM_PINS];
- u32 nr_rt_entries;
- /*
- * Array indexed by gsi. Each entry contains list of irq chips
- * the gsi is connected to.
- */
- struct hlist_head map[0];
-};
-
int kvm_irq_map_gsi(struct kvm *kvm,
struct kvm_kernel_irq_routing_entry *entries, int gsi)
{
@@ -227,6 +217,8 @@ int kvm_set_irq_routing(struct kvm *kvm,
kvm_irq_routing_update(kvm);
mutex_unlock(&kvm->irq_lock);
+ kvm_arch_irq_routing_update(kvm);
+
synchronize_srcu_expedited(&kvm->irq_srcu);
new = old;
--
1.8.3.1
^ permalink raw reply related [flat|nested] 17+ messages in thread* RE: [PATCH 8/9] KVM: x86: Add EOI exit bitmap inference
2015-08-05 15:23 ` [PATCH 8/9] KVM: x86: Add EOI exit bitmap inference Paolo Bonzini
@ 2015-08-07 5:43 ` Wu, Feng
2015-08-07 7:32 ` Paolo Bonzini
2015-08-07 7:46 ` Wu, Feng
1 sibling, 1 reply; 17+ messages in thread
From: Wu, Feng @ 2015-08-07 5:43 UTC (permalink / raw)
To: Paolo Bonzini, linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Steve Rutherford, rkrcmar@redhat.com, Wu, Feng
> -----Original Message-----
> From: kvm-owner@vger.kernel.org [mailto:kvm-owner@vger.kernel.org] On
> Behalf Of Paolo Bonzini
> Sent: Wednesday, August 05, 2015 11:24 PM
> To: linux-kernel@vger.kernel.org; kvm@vger.kernel.org
> Cc: Steve Rutherford; rkrcmar@redhat.com
> Subject: [PATCH 8/9] KVM: x86: Add EOI exit bitmap inference
>
> From: Steve Rutherford <srutherford@google.com>
>
> In order to support a userspace IOAPIC interacting with an in kernel
> APIC, the EOI exit bitmaps need to be configurable.
>
> If the IOAPIC is in userspace (i.e. the irqchip has been split), the
> EOI exit bitmaps will be set whenever the GSI Routes are configured.
> In particular, for the low MSI routes are reservable for userspace
> IOAPICs. For these MSI routes, the EOI Exit bit corresponding to the
> destination vector of the route will be set for the destination VCPU.
>
> The intention is for the userspace IOAPICs to use the reservable MSI
> routes to inject interrupts into the guest.
>
> This is a slight abuse of the notion of an MSI Route, given that MSIs
> classically bypass the IOAPIC. It might be worthwhile to add an
> additional route type to improve clarity.
>
> Compile tested for Intel x86.
>
> Signed-off-by: Steve Rutherford <srutherford@google.com>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
> Documentation/virtual/kvm/api.txt | 9 ++++++---
> arch/x86/include/asm/kvm_host.h | 1 +
> arch/x86/kvm/ioapic.h | 2 ++
> arch/x86/kvm/irq_comm.c | 42
> +++++++++++++++++++++++++++++++++++++++
> arch/x86/kvm/lapic.c | 3 +--
> arch/x86/kvm/x86.c | 9 ++++++++-
> include/linux/kvm_host.h | 17 ++++++++++++++++
> virt/kvm/irqchip.c | 12 ++---------
> 8 files changed, 79 insertions(+), 16 deletions(-)
>
> diff --git a/Documentation/virtual/kvm/api.txt
> b/Documentation/virtual/kvm/api.txt
> index bda6cb747b23..dcd748e2d46d 100644
> --- a/Documentation/virtual/kvm/api.txt
> +++ b/Documentation/virtual/kvm/api.txt
> @@ -3635,7 +3635,7 @@ KVM handlers should exit to userspace with rc =
> -EREMOTE.
> 7.5 KVM_CAP_SPLIT_IRQCHIP
>
> Architectures: x86
> -Parameters: None
> +Parameters: args[0] - number of routes reserved for userspace IOAPICs
> Returns: 0 on success, -1 on error
>
> Create a local apic for each processor in the kernel. This can be used
> @@ -3643,8 +3643,11 @@ instead of KVM_CREATE_IRQCHIP if the userspace
> VMM wishes to emulate the
> IOAPIC and PIC (and also the PIT, even though this has to be enabled
> separately).
>
> -This supersedes KVM_CREATE_IRQCHIP, creating only local APICs, but no in
> kernel
> -IOAPIC or PIC. This also enables in kernel routing of interrupt requests.
> +This capability also enables in kernel routing of interrupt requests;
> +when KVM_CAP_SPLIT_IRQCHIP only routes of KVM_IRQ_ROUTING_MSI type
> are
> +used in the IRQ routing table. The first args[0] MSI routes are reserved
> +for the IOAPIC pins. Whenever the LAPIC receives an EOI for these routes,
> +a KVM_EXIT_IOAPIC_EOI vmexit will be reported to userspace.
>
> Fails if VCPU has already been created, or if the irqchip is already in the
> kernel (i.e. KVM_CREATE_IRQCHIP has already been called).
> diff --git a/arch/x86/include/asm/kvm_host.h
> b/arch/x86/include/asm/kvm_host.h
> index 4294722dfd1d..4bc714f7b164 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -687,6 +687,7 @@ struct kvm_arch {
> u64 disabled_quirks;
>
> bool irqchip_split;
> + u8 nr_reserved_ioapic_pins;
> };
>
> struct kvm_vm_stat {
> diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h
> index a8842c0dee73..084617d37c74 100644
> --- a/arch/x86/kvm/ioapic.h
> +++ b/arch/x86/kvm/ioapic.h
> @@ -9,6 +9,7 @@ struct kvm;
> struct kvm_vcpu;
>
> #define IOAPIC_NUM_PINS KVM_IOAPIC_NUM_PINS
> +#define MAX_NR_RESERVED_IOAPIC_PINS KVM_MAX_IRQ_ROUTES
> #define IOAPIC_VERSION_ID 0x11 /* IOAPIC version */
> #define IOAPIC_EDGE_TRIG 0
> #define IOAPIC_LEVEL_TRIG 1
> @@ -121,5 +122,6 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct
> kvm_lapic *src,
> int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
> int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
> void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
> +void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
>
> #endif
> diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
> index 67f6b62a6814..177460998bb0 100644
> --- a/arch/x86/kvm/irq_comm.c
> +++ b/arch/x86/kvm/irq_comm.c
> @@ -335,3 +335,45 @@ int kvm_setup_empty_irq_routing(struct kvm *kvm)
> {
> return kvm_set_irq_routing(kvm, empty_routing, 0, 0);
> }
> +
> +void kvm_arch_irq_routing_update(struct kvm *kvm)
> +{
> + if (ioapic_in_kernel(kvm) || !irqchip_in_kernel(kvm))
> + return;
> + kvm_make_scan_ioapic_request(kvm);
> +}
> +
> +void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
> +{
> + struct kvm *kvm = vcpu->kvm;
> + struct kvm_kernel_irq_routing_entry *entry;
> + struct kvm_irq_routing_table *table;
> + u32 i, nr_ioapic_pins;
> + int idx;
> +
> + /* kvm->irq_routing must be read after clearing
> + * KVM_SCAN_IOAPIC. */
> + smp_mb();
> + idx = srcu_read_lock(&kvm->irq_srcu);
> + table = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
> + nr_ioapic_pins = min_t(u32, table->nr_rt_entries,
> + kvm->arch.nr_reserved_ioapic_pins);
> + for (i = 0; i < nr_ioapic_pins; ++i) {
> + hlist_for_each_entry(entry, &table->map[i], link) {
> + u32 dest_id, dest_mode;
> +
> + if (entry->type != KVM_IRQ_ROUTING_MSI)
> + continue;
> + dest_id = (entry->msi.address_lo >> 12) & 0xff;
> + dest_mode = (entry->msi.address_lo >> 2) & 0x1;
> + if (kvm_apic_match_dest(vcpu, NULL, 0, dest_id,
> + dest_mode)) {
> + u32 vector = entry->msi.data & 0xff;
> +
> + __set_bit(vector,
> + (unsigned long *) eoi_exit_bitmap);
> + }
> + }
> + }
> + srcu_read_unlock(&kvm->irq_srcu, idx);
> +}
> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> index 14b5603ef6c5..38c580aa27c2 100644
> --- a/arch/x86/kvm/lapic.c
> +++ b/arch/x86/kvm/lapic.c
> @@ -209,8 +209,7 @@ out:
> if (old)
> kfree_rcu(old, rcu);
>
> - if (ioapic_in_kernel(kvm))
> - kvm_vcpu_request_scan_ioapic(kvm);
> + kvm_make_scan_ioapic_request(kvm);
> }
>
> static inline void apic_set_spiv(struct kvm_lapic *apic, u32 val)
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 16e2f3c577c7..c9fb11491aa3 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -3571,6 +3571,9 @@ static int kvm_vm_ioctl_enable_cap(struct kvm
> *kvm,
> break;
> case KVM_CAP_SPLIT_IRQCHIP: {
> mutex_lock(&kvm->lock);
> + r = -EINVAL;
> + if (cap->args[0] > MAX_NR_RESERVED_IOAPIC_PINS)
> + goto split_irqchip_unlock;
> r = -EEXIST;
> if (irqchip_in_kernel(kvm))
> goto split_irqchip_unlock;
> @@ -3582,6 +3585,7 @@ static int kvm_vm_ioctl_enable_cap(struct kvm
> *kvm,
> /* Pairs with irqchip_in_kernel. */
> smp_wmb();
> kvm->arch.irqchip_split = true;
> + kvm->arch.nr_reserved_ioapic_pins = cap->args[0];
> r = 0;
> split_irqchip_unlock:
> mutex_unlock(&kvm->lock);
> @@ -6173,7 +6177,10 @@ static void vcpu_scan_ioapic(struct kvm_vcpu
> *vcpu)
>
> memset(vcpu->arch.eoi_exit_bitmap, 0, 256 / 8);
>
> - kvm_ioapic_scan_entry(vcpu, vcpu->arch.eoi_exit_bitmap);
> + if (irqchip_split(vcpu->kvm))
> + kvm_scan_ioapic_routes(vcpu, vcpu->arch.eoi_exit_bitmap);
> + else
> + kvm_ioapic_scan_entry(vcpu, vcpu->arch.eoi_exit_bitmap);
> kvm_x86_ops->load_eoi_exitmap(vcpu);
> }
>
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index 653d494e13d1..27ccdf91a465 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -329,6 +329,19 @@ struct kvm_kernel_irq_routing_entry {
> struct hlist_node link;
> };
>
> +#ifdef CONFIG_HAVE_KVM_IRQCHIP
> +struct kvm_irq_routing_table {
> + int chip[KVM_NR_IRQCHIPS][KVM_IRQCHIP_NUM_PINS];
> + struct kvm_kernel_irq_routing_entry *rt_entries;
This filed doesn't exist anymore. In fact, this changes is also in my
VT-d PI patches. If this series get merged first, I can rebase my
patches then.
Thanks,
Feng
> + u32 nr_rt_entries;
> + /*
> + * Array indexed by gsi. Each entry contains list of irq chips
> + * the gsi is connected to.
> + */
> + struct hlist_head map[0];
> +};
> +#endif
> +
> #ifndef KVM_PRIVATE_MEM_SLOTS
> #define KVM_PRIVATE_MEM_SLOTS 0
> #endif
> @@ -455,10 +468,14 @@ void vcpu_put(struct kvm_vcpu *vcpu);
>
> #ifdef __KVM_HAVE_IOAPIC
> void kvm_vcpu_request_scan_ioapic(struct kvm *kvm);
> +void kvm_arch_irq_routing_update(struct kvm *kvm);
> #else
> static inline void kvm_vcpu_request_scan_ioapic(struct kvm *kvm)
> {
> }
> +static inline void kvm_arch_irq_routing_update(struct kvm *kvm)
> +{
> +}
> #endif
>
> #ifdef CONFIG_HAVE_KVM_IRQFD
> diff --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c
> index 21c14244f4c4..4f85c6ee96dc 100644
> --- a/virt/kvm/irqchip.c
> +++ b/virt/kvm/irqchip.c
> @@ -31,16 +31,6 @@
> #include <trace/events/kvm.h>
> #include "irq.h"
>
> -struct kvm_irq_routing_table {
> - int chip[KVM_NR_IRQCHIPS][KVM_IRQCHIP_NUM_PINS];
> - u32 nr_rt_entries;
> - /*
> - * Array indexed by gsi. Each entry contains list of irq chips
> - * the gsi is connected to.
> - */
> - struct hlist_head map[0];
> -};
> -
> int kvm_irq_map_gsi(struct kvm *kvm,
> struct kvm_kernel_irq_routing_entry *entries, int gsi)
> {
> @@ -227,6 +217,8 @@ int kvm_set_irq_routing(struct kvm *kvm,
> kvm_irq_routing_update(kvm);
> mutex_unlock(&kvm->irq_lock);
>
> + kvm_arch_irq_routing_update(kvm);
> +
> synchronize_srcu_expedited(&kvm->irq_srcu);
>
> new = old;
> --
> 1.8.3.1
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe kvm" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 17+ messages in thread* Re: [PATCH 8/9] KVM: x86: Add EOI exit bitmap inference
2015-08-07 5:43 ` Wu, Feng
@ 2015-08-07 7:32 ` Paolo Bonzini
0 siblings, 0 replies; 17+ messages in thread
From: Paolo Bonzini @ 2015-08-07 7:32 UTC (permalink / raw)
To: Wu, Feng, linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Steve Rutherford, rkrcmar@redhat.com
On 07/08/2015 07:43, Wu, Feng wrote:
>> > +#ifdef CONFIG_HAVE_KVM_IRQCHIP
>> > +struct kvm_irq_routing_table {
>> > + int chip[KVM_NR_IRQCHIPS][KVM_IRQCHIP_NUM_PINS];
>> > + struct kvm_kernel_irq_routing_entry *rt_entries;
> This filed doesn't exist anymore. In fact, this changes is also in my
> VT-d PI patches. If this series get merged first, I can rebase my
> patches then.
Thanks!
Paolo
^ permalink raw reply [flat|nested] 17+ messages in thread
* RE: [PATCH 8/9] KVM: x86: Add EOI exit bitmap inference
2015-08-05 15:23 ` [PATCH 8/9] KVM: x86: Add EOI exit bitmap inference Paolo Bonzini
2015-08-07 5:43 ` Wu, Feng
@ 2015-08-07 7:46 ` Wu, Feng
2015-08-07 10:16 ` Paolo Bonzini
1 sibling, 1 reply; 17+ messages in thread
From: Wu, Feng @ 2015-08-07 7:46 UTC (permalink / raw)
To: Paolo Bonzini, linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Steve Rutherford, rkrcmar@redhat.com, Wu, Feng
> -----Original Message-----
> From: kvm-owner@vger.kernel.org [mailto:kvm-owner@vger.kernel.org] On
> Behalf Of Paolo Bonzini
> Sent: Wednesday, August 05, 2015 11:24 PM
> To: linux-kernel@vger.kernel.org; kvm@vger.kernel.org
> Cc: Steve Rutherford; rkrcmar@redhat.com
> Subject: [PATCH 8/9] KVM: x86: Add EOI exit bitmap inference
>
> From: Steve Rutherford <srutherford@google.com>
>
> In order to support a userspace IOAPIC interacting with an in kernel
> APIC, the EOI exit bitmaps need to be configurable.
>
> If the IOAPIC is in userspace (i.e. the irqchip has been split), the
> EOI exit bitmaps will be set whenever the GSI Routes are configured.
> In particular, for the low MSI routes are reservable for userspace
> IOAPICs. For these MSI routes, the EOI Exit bit corresponding to the
> destination vector of the route will be set for the destination VCPU.
>
> The intention is for the userspace IOAPICs to use the reservable MSI
> routes to inject interrupts into the guest.
>
> This is a slight abuse of the notion of an MSI Route, given that MSIs
> classically bypass the IOAPIC. It might be worthwhile to add an
> additional route type to improve clarity.
>
> Compile tested for Intel x86.
>
> Signed-off-by: Steve Rutherford <srutherford@google.com>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
> Documentation/virtual/kvm/api.txt | 9 ++++++---
> arch/x86/include/asm/kvm_host.h | 1 +
> arch/x86/kvm/ioapic.h | 2 ++
> arch/x86/kvm/irq_comm.c | 42
> +++++++++++++++++++++++++++++++++++++++
> arch/x86/kvm/lapic.c | 3 +--
> arch/x86/kvm/x86.c | 9 ++++++++-
> include/linux/kvm_host.h | 17 ++++++++++++++++
> virt/kvm/irqchip.c | 12 ++---------
> 8 files changed, 79 insertions(+), 16 deletions(-)
>
> diff --git a/Documentation/virtual/kvm/api.txt
> b/Documentation/virtual/kvm/api.txt
> index bda6cb747b23..dcd748e2d46d 100644
> --- a/Documentation/virtual/kvm/api.txt
> +++ b/Documentation/virtual/kvm/api.txt
> @@ -3635,7 +3635,7 @@ KVM handlers should exit to userspace with rc =
> -EREMOTE.
> 7.5 KVM_CAP_SPLIT_IRQCHIP
>
> Architectures: x86
> -Parameters: None
> +Parameters: args[0] - number of routes reserved for userspace IOAPICs
> Returns: 0 on success, -1 on error
>
> Create a local apic for each processor in the kernel. This can be used
> @@ -3643,8 +3643,11 @@ instead of KVM_CREATE_IRQCHIP if the userspace
> VMM wishes to emulate the
> IOAPIC and PIC (and also the PIT, even though this has to be enabled
> separately).
>
> -This supersedes KVM_CREATE_IRQCHIP, creating only local APICs, but no in
> kernel
> -IOAPIC or PIC. This also enables in kernel routing of interrupt requests.
> +This capability also enables in kernel routing of interrupt requests;
> +when KVM_CAP_SPLIT_IRQCHIP only routes of KVM_IRQ_ROUTING_MSI type
> are
> +used in the IRQ routing table. The first args[0] MSI routes are reserved
> +for the IOAPIC pins. Whenever the LAPIC receives an EOI for these routes,
> +a KVM_EXIT_IOAPIC_EOI vmexit will be reported to userspace.
>
> Fails if VCPU has already been created, or if the irqchip is already in the
> kernel (i.e. KVM_CREATE_IRQCHIP has already been called).
> diff --git a/arch/x86/include/asm/kvm_host.h
> b/arch/x86/include/asm/kvm_host.h
> index 4294722dfd1d..4bc714f7b164 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -687,6 +687,7 @@ struct kvm_arch {
> u64 disabled_quirks;
>
> bool irqchip_split;
> + u8 nr_reserved_ioapic_pins;
> };
>
> struct kvm_vm_stat {
> diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h
> index a8842c0dee73..084617d37c74 100644
> --- a/arch/x86/kvm/ioapic.h
> +++ b/arch/x86/kvm/ioapic.h
> @@ -9,6 +9,7 @@ struct kvm;
> struct kvm_vcpu;
>
> #define IOAPIC_NUM_PINS KVM_IOAPIC_NUM_PINS
> +#define MAX_NR_RESERVED_IOAPIC_PINS KVM_MAX_IRQ_ROUTES
> #define IOAPIC_VERSION_ID 0x11 /* IOAPIC version */
> #define IOAPIC_EDGE_TRIG 0
> #define IOAPIC_LEVEL_TRIG 1
> @@ -121,5 +122,6 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct
> kvm_lapic *src,
> int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
> int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
> void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
> +void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
>
> #endif
> diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c
> index 67f6b62a6814..177460998bb0 100644
> --- a/arch/x86/kvm/irq_comm.c
> +++ b/arch/x86/kvm/irq_comm.c
> @@ -335,3 +335,45 @@ int kvm_setup_empty_irq_routing(struct kvm *kvm)
> {
> return kvm_set_irq_routing(kvm, empty_routing, 0, 0);
> }
> +
> +void kvm_arch_irq_routing_update(struct kvm *kvm)
> +{
> + if (ioapic_in_kernel(kvm) || !irqchip_in_kernel(kvm))
> + return;
> + kvm_make_scan_ioapic_request(kvm);
> +}
> +
> +void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
> +{
> + struct kvm *kvm = vcpu->kvm;
> + struct kvm_kernel_irq_routing_entry *entry;
> + struct kvm_irq_routing_table *table;
> + u32 i, nr_ioapic_pins;
> + int idx;
> +
> + /* kvm->irq_routing must be read after clearing
> + * KVM_SCAN_IOAPIC. */
> + smp_mb();
> + idx = srcu_read_lock(&kvm->irq_srcu);
> + table = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
> + nr_ioapic_pins = min_t(u32, table->nr_rt_entries,
> + kvm->arch.nr_reserved_ioapic_pins);
> + for (i = 0; i < nr_ioapic_pins; ++i) {
> + hlist_for_each_entry(entry, &table->map[i], link) {
> + u32 dest_id, dest_mode;
> +
> + if (entry->type != KVM_IRQ_ROUTING_MSI)
> + continue;
If I understand it correctly, here you reserve the low part of the routing
table, and insert entries with KVM_IRQ_ROUTING_MSI type in them,
then you use this as a hint to KVM to set the EOI bit map. I have two
concerns:
- Currently, GSI 2 is used for MSI routing, I want to make sure after this
patch, whether GSI 2 can still be used for _real_ MSI routing, if it can,
does everything work correctly?
- Now, KVM_IRQ_ROUTING_MSI and KVM_IRQ_ROUTING_IRQCHIP
type entries cannot share the same map[gsi] (pls refer to the following
code), so where should be the IOAPIC entries exist in the map[] array?
static int setup_routing_entry(struct kvm_irq_routing_table *rt,
struct kvm_kernel_irq_routing_entry *e,
const struct kvm_irq_routing_entry *ue)
{
......
/*
* Do not allow GSI to be mapped to the same irqchip more than once.
* Allow only one to one mapping between GSI and MSI.
*/
hlist_for_each_entry(ei, &rt->map[ue->gsi], link)
if (ei->type == KVM_IRQ_ROUTING_MSI ||
ue->type == KVM_IRQ_ROUTING_MSI ||
ue->u.irqchip.irqchip == ei->irqchip.irqchip)
return r;
......
}
Thanks,
Feng
> + dest_id = (entry->msi.address_lo >> 12) & 0xff;
> + dest_mode = (entry->msi.address_lo >> 2) & 0x1;
> + if (kvm_apic_match_dest(vcpu, NULL, 0, dest_id,
> + dest_mode)) {
> + u32 vector = entry->msi.data & 0xff;
> +
> + __set_bit(vector,
> + (unsigned long *) eoi_exit_bitmap);
> + }
> + }
> + }
> + srcu_read_unlock(&kvm->irq_srcu, idx);
> +}
> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> index 14b5603ef6c5..38c580aa27c2 100644
> --- a/arch/x86/kvm/lapic.c
> +++ b/arch/x86/kvm/lapic.c
> @@ -209,8 +209,7 @@ out:
> if (old)
> kfree_rcu(old, rcu);
>
> - if (ioapic_in_kernel(kvm))
> - kvm_vcpu_request_scan_ioapic(kvm);
> + kvm_make_scan_ioapic_request(kvm);
> }
>
> static inline void apic_set_spiv(struct kvm_lapic *apic, u32 val)
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 16e2f3c577c7..c9fb11491aa3 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -3571,6 +3571,9 @@ static int kvm_vm_ioctl_enable_cap(struct kvm
> *kvm,
> break;
> case KVM_CAP_SPLIT_IRQCHIP: {
> mutex_lock(&kvm->lock);
> + r = -EINVAL;
> + if (cap->args[0] > MAX_NR_RESERVED_IOAPIC_PINS)
> + goto split_irqchip_unlock;
> r = -EEXIST;
> if (irqchip_in_kernel(kvm))
> goto split_irqchip_unlock;
> @@ -3582,6 +3585,7 @@ static int kvm_vm_ioctl_enable_cap(struct kvm
> *kvm,
> /* Pairs with irqchip_in_kernel. */
> smp_wmb();
> kvm->arch.irqchip_split = true;
> + kvm->arch.nr_reserved_ioapic_pins = cap->args[0];
> r = 0;
> split_irqchip_unlock:
> mutex_unlock(&kvm->lock);
> @@ -6173,7 +6177,10 @@ static void vcpu_scan_ioapic(struct kvm_vcpu
> *vcpu)
>
> memset(vcpu->arch.eoi_exit_bitmap, 0, 256 / 8);
>
> - kvm_ioapic_scan_entry(vcpu, vcpu->arch.eoi_exit_bitmap);
> + if (irqchip_split(vcpu->kvm))
> + kvm_scan_ioapic_routes(vcpu, vcpu->arch.eoi_exit_bitmap);
> + else
> + kvm_ioapic_scan_entry(vcpu, vcpu->arch.eoi_exit_bitmap);
> kvm_x86_ops->load_eoi_exitmap(vcpu);
> }
>
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index 653d494e13d1..27ccdf91a465 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -329,6 +329,19 @@ struct kvm_kernel_irq_routing_entry {
> struct hlist_node link;
> };
>
> +#ifdef CONFIG_HAVE_KVM_IRQCHIP
> +struct kvm_irq_routing_table {
> + int chip[KVM_NR_IRQCHIPS][KVM_IRQCHIP_NUM_PINS];
> + struct kvm_kernel_irq_routing_entry *rt_entries;
> + u32 nr_rt_entries;
> + /*
> + * Array indexed by gsi. Each entry contains list of irq chips
> + * the gsi is connected to.
> + */
> + struct hlist_head map[0];
> +};
> +#endif
> +
> #ifndef KVM_PRIVATE_MEM_SLOTS
> #define KVM_PRIVATE_MEM_SLOTS 0
> #endif
> @@ -455,10 +468,14 @@ void vcpu_put(struct kvm_vcpu *vcpu);
>
> #ifdef __KVM_HAVE_IOAPIC
> void kvm_vcpu_request_scan_ioapic(struct kvm *kvm);
> +void kvm_arch_irq_routing_update(struct kvm *kvm);
> #else
> static inline void kvm_vcpu_request_scan_ioapic(struct kvm *kvm)
> {
> }
> +static inline void kvm_arch_irq_routing_update(struct kvm *kvm)
> +{
> +}
> #endif
>
> #ifdef CONFIG_HAVE_KVM_IRQFD
> diff --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c
> index 21c14244f4c4..4f85c6ee96dc 100644
> --- a/virt/kvm/irqchip.c
> +++ b/virt/kvm/irqchip.c
> @@ -31,16 +31,6 @@
> #include <trace/events/kvm.h>
> #include "irq.h"
>
> -struct kvm_irq_routing_table {
> - int chip[KVM_NR_IRQCHIPS][KVM_IRQCHIP_NUM_PINS];
> - u32 nr_rt_entries;
> - /*
> - * Array indexed by gsi. Each entry contains list of irq chips
> - * the gsi is connected to.
> - */
> - struct hlist_head map[0];
> -};
> -
> int kvm_irq_map_gsi(struct kvm *kvm,
> struct kvm_kernel_irq_routing_entry *entries, int gsi)
> {
> @@ -227,6 +217,8 @@ int kvm_set_irq_routing(struct kvm *kvm,
> kvm_irq_routing_update(kvm);
> mutex_unlock(&kvm->irq_lock);
>
> + kvm_arch_irq_routing_update(kvm);
> +
> synchronize_srcu_expedited(&kvm->irq_srcu);
>
> new = old;
> --
> 1.8.3.1
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe kvm" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 17+ messages in thread* Re: [PATCH 8/9] KVM: x86: Add EOI exit bitmap inference
2015-08-07 7:46 ` Wu, Feng
@ 2015-08-07 10:16 ` Paolo Bonzini
2015-08-07 22:55 ` Wu, Feng
0 siblings, 1 reply; 17+ messages in thread
From: Paolo Bonzini @ 2015-08-07 10:16 UTC (permalink / raw)
To: Wu, Feng, linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Steve Rutherford, rkrcmar@redhat.com
On 07/08/2015 09:46, Wu, Feng wrote:
> If I understand it correctly, here you reserve the low part of the routing
> table, and insert entries with KVM_IRQ_ROUTING_MSI type in them,
> then you use this as a hint to KVM to set the EOI bit map. I have two
> concerns:
>
> - Currently, GSI 2 is used for MSI routing, I want to make sure after this
> patch, whether GSI 2 can still be used for _real_ MSI routing, if it can,
> does everything work correctly?
The patch has no effect if you use the in-kernel IOAPIC. If you use a
userspace IOAPIC you won't be able to use GSI 2 for MSI routing because
it falls in the reserved range.
> - Now, KVM_IRQ_ROUTING_MSI and KVM_IRQ_ROUTING_IRQCHIP
> type entries cannot share the same map[gsi] (pls refer to the following
> code), so where should be the IOAPIC entries exist in the map[] array?
With split irqchip, only KVM_IRQ_ROUTING_MSI is used. Does this answer
your question?
Paolo
> static int setup_routing_entry(struct kvm_irq_routing_table *rt,
> struct kvm_kernel_irq_routing_entry *e,
> const struct kvm_irq_routing_entry *ue)
> {
>
> ......
>
> /*
> * Do not allow GSI to be mapped to the same irqchip more than once.
> * Allow only one to one mapping between GSI and MSI.
> */
> hlist_for_each_entry(ei, &rt->map[ue->gsi], link)
> if (ei->type == KVM_IRQ_ROUTING_MSI ||
> ue->type == KVM_IRQ_ROUTING_MSI ||
> ue->u.irqchip.irqchip == ei->irqchip.irqchip)
> return r;
>
> ......
> }
^ permalink raw reply [flat|nested] 17+ messages in thread* RE: [PATCH 8/9] KVM: x86: Add EOI exit bitmap inference
2015-08-07 10:16 ` Paolo Bonzini
@ 2015-08-07 22:55 ` Wu, Feng
0 siblings, 0 replies; 17+ messages in thread
From: Wu, Feng @ 2015-08-07 22:55 UTC (permalink / raw)
To: Paolo Bonzini, linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Steve Rutherford, rkrcmar@redhat.com, Wu, Feng
> -----Original Message-----
> From: Paolo Bonzini [mailto:paolo.bonzini@gmail.com] On Behalf Of Paolo
> Bonzini
> Sent: Friday, August 07, 2015 6:17 PM
> To: Wu, Feng; linux-kernel@vger.kernel.org; kvm@vger.kernel.org
> Cc: Steve Rutherford; rkrcmar@redhat.com
> Subject: Re: [PATCH 8/9] KVM: x86: Add EOI exit bitmap inference
>
>
>
> On 07/08/2015 09:46, Wu, Feng wrote:
> > If I understand it correctly, here you reserve the low part of the routing
> > table, and insert entries with KVM_IRQ_ROUTING_MSI type in them,
> > then you use this as a hint to KVM to set the EOI bit map. I have two
> > concerns:
> >
> > - Currently, GSI 2 is used for MSI routing, I want to make sure after this
> > patch, whether GSI 2 can still be used for _real_ MSI routing, if it can,
> > does everything work correctly?
>
> The patch has no effect if you use the in-kernel IOAPIC. If you use a
> userspace IOAPIC you won't be able to use GSI 2 for MSI routing because
> it falls in the reserved range.
Good to know this, it addresses my concern, thanks!
>
> > - Now, KVM_IRQ_ROUTING_MSI and KVM_IRQ_ROUTING_IRQCHIP
> > type entries cannot share the same map[gsi] (pls refer to the following
> > code), so where should be the IOAPIC entries exist in the map[] array?
>
> With split irqchip, only KVM_IRQ_ROUTING_MSI is used. Does this answer
> your question?
Ah, I got it, since the IOAPIC is in userspace, there is no need to add the IOAPIC
routing information in the routing table. Thanks for the clarification!
Thanks,
Feng
>
> Paolo
>
> > static int setup_routing_entry(struct kvm_irq_routing_table *rt,
> > struct kvm_kernel_irq_routing_entry
> *e,
> > const struct kvm_irq_routing_entry
> *ue)
> > {
> >
> > ......
> >
> > /*
> > * Do not allow GSI to be mapped to the same irqchip more than
> once.
> > * Allow only one to one mapping between GSI and MSI.
> > */
> > hlist_for_each_entry(ei, &rt->map[ue->gsi], link)
> > if (ei->type == KVM_IRQ_ROUTING_MSI ||
> > ue->type == KVM_IRQ_ROUTING_MSI ||
> > ue->u.irqchip.irqchip == ei->irqchip.irqchip)
> > return r;
> >
> > ......
> > }
^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH 9/9] KVM: x86: Add support for local interrupt requests from userspace
2015-08-05 15:23 [PATCH 0/9] split irqchip series Paolo Bonzini
` (7 preceding siblings ...)
2015-08-05 15:23 ` [PATCH 8/9] KVM: x86: Add EOI exit bitmap inference Paolo Bonzini
@ 2015-08-05 15:23 ` Paolo Bonzini
8 siblings, 0 replies; 17+ messages in thread
From: Paolo Bonzini @ 2015-08-05 15:23 UTC (permalink / raw)
To: linux-kernel, kvm; +Cc: Steve Rutherford, rkrcmar
From: Steve Rutherford <srutherford@google.com>
In order to enable userspace PIC support, the userspace PIC needs to
be able to inject local interrupts even when the APICs are in the
kernel.
KVM_INTERRUPT now supports sending local interrupts to an APIC when
APICs are in the kernel.
The ready_for_interrupt_request flag is now only set when the CPU/APIC
will immediately accept and inject an interrupt (i.e. APIC has not
masked the PIC).
When the PIC wishes to initiate an INTA cycle with, say, CPU0, it
kicks CPU0 out of the guest, and renedezvous with CPU0 once it arrives
in userspace.
When the CPU/APIC unmasks the PIC, a KVM_EXIT_IRQ_WINDOW_OPEN is
triggered, so that userspace has a chance to inject a PIC interrupt
if it had been pending.
Overall, this design can lead to a small number of spurious userspace
renedezvous. In particular, whenever the PIC transistions from low to
high while it is masked and whenever the PIC becomes unmasked while
it is low.
Note: this does not buffer more than one local interrupt in the
kernel, so the VMM needs to enter the guest in order to complete
interrupt injection before injecting an additional interrupt.
Compiles for x86.
Can pass the KVM Unit Tests.
Signed-off-by: Steve Rutherford <srutherford@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
Documentation/virtual/kvm/api.txt | 14 +++++++++----
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/irq.c | 32 +++++++++++++++++++++++------
arch/x86/kvm/irq.h | 8 ++++++++
arch/x86/kvm/x86.c | 42 ++++++++++++++++++++++++++++++---------
5 files changed, 78 insertions(+), 19 deletions(-)
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index dcd748e2d46d..3c714d43a717 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -401,10 +401,9 @@ Capability: basic
Architectures: x86, ppc, mips
Type: vcpu ioctl
Parameters: struct kvm_interrupt (in)
-Returns: 0 on success, -1 on error
+Returns: 0 on success, negative on failure.
-Queues a hardware interrupt vector to be injected. This is only
-useful if in-kernel local APIC or equivalent is not used.
+Queues a hardware interrupt vector to be injected.
/* for KVM_INTERRUPT */
struct kvm_interrupt {
@@ -414,7 +413,14 @@ struct kvm_interrupt {
X86:
-Note 'irq' is an interrupt vector, not an interrupt pin or line.
+Returns: 0 on success,
+ -EEXIST if an interrupt is already enqueued
+ -EINVAL the the irq number is invalid
+ -ENXIO if the PIC is in the kernel
+ -EFAULT if the pointer is invalid
+
+Note 'irq' is an interrupt vector, not an interrupt pin or line. This
+ioctl is useful if the in-kernel PIC is not used.
PPC:
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 4bc714f7b164..09acaa64ef8e 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -575,6 +575,7 @@ struct kvm_vcpu_arch {
} pv;
int pending_ioapic_eoi;
+ int pending_external_vector;
};
struct kvm_lpage_info {
diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index b653ae202c8e..097060e33bd6 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -38,14 +38,27 @@ int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
EXPORT_SYMBOL(kvm_cpu_has_pending_timer);
/*
+ * check if there is a pending userspace external interrupt
+ */
+static int pending_userspace_extint(struct kvm_vcpu *v)
+{
+ return v->arch.pending_external_vector != -1;
+}
+
+/*
* check if there is pending interrupt from
* non-APIC source without intack.
*/
static int kvm_cpu_has_extint(struct kvm_vcpu *v)
{
- if (kvm_apic_accept_pic_intr(v))
- return pic_irqchip(v->kvm)->output; /* PIC */
- else
+ u8 accept = kvm_apic_accept_pic_intr(v);
+
+ if (accept) {
+ if (irqchip_split(v->kvm))
+ return pending_userspace_extint(v);
+ else
+ return pic_irqchip(v->kvm)->output;
+ } else
return 0;
}
@@ -91,9 +104,16 @@ EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt);
*/
static int kvm_cpu_get_extint(struct kvm_vcpu *v)
{
- if (kvm_cpu_has_extint(v))
- return kvm_pic_read_irq(v->kvm); /* PIC */
- return -1;
+ if (kvm_cpu_has_extint(v)) {
+ if (irqchip_split(v->kvm)) {
+ int vector = v->arch.pending_external_vector;
+
+ v->arch.pending_external_vector = -1;
+ return vector;
+ } else
+ return kvm_pic_read_irq(v->kvm); /* PIC */
+ } else
+ return -1;
}
/*
diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index 2f9703dcd913..ae5c78f2337d 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -83,6 +83,14 @@ static inline struct kvm_pic *pic_irqchip(struct kvm *kvm)
return kvm->arch.vpic;
}
+static inline int pic_in_kernel(struct kvm *kvm)
+{
+ int ret;
+
+ ret = (pic_irqchip(kvm) != NULL);
+ return ret;
+}
+
static inline int irqchip_split(struct kvm *kvm)
{
return kvm->arch.irqchip_split;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c9fb11491aa3..e5850076bf7b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2675,12 +2675,24 @@ static int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
{
if (irq->irq >= KVM_NR_INTERRUPTS)
return -EINVAL;
- if (irqchip_in_kernel(vcpu->kvm))
+
+ if (!irqchip_in_kernel(vcpu->kvm)) {
+ kvm_queue_interrupt(vcpu, irq->irq, false);
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
+ return 0;
+ }
+
+ /*
+ * With in-kernel LAPIC, we only use this to inject EXTINT, so
+ * fail for in-kernel 8259.
+ */
+ if (pic_in_kernel(vcpu->kvm))
return -ENXIO;
- kvm_queue_interrupt(vcpu, irq->irq, false);
- kvm_make_request(KVM_REQ_EVENT, vcpu);
+ if (vcpu->arch.pending_external_vector != -1)
+ return -EEXIST;
+ vcpu->arch.pending_external_vector = irq->irq;
return 0;
}
@@ -5809,9 +5821,15 @@ static int emulator_fix_hypercall(struct x86_emulate_ctxt *ctxt)
*/
static int dm_request_for_irq_injection(struct kvm_vcpu *vcpu)
{
- return (!irqchip_in_kernel(vcpu->kvm) && !kvm_cpu_has_interrupt(vcpu) &&
- vcpu->run->request_interrupt_window &&
- kvm_arch_interrupt_allowed(vcpu));
+ if (!vcpu->run->request_interrupt_window || pic_in_kernel(vcpu->kvm))
+ return false;
+
+ if (kvm_cpu_has_interrupt(vcpu))
+ return false;
+
+ return (irqchip_split(vcpu->kvm)
+ ? kvm_apic_accept_pic_intr(vcpu)
+ : kvm_arch_interrupt_allowed(vcpu));
}
static void post_kvm_run_save(struct kvm_vcpu *vcpu)
@@ -5822,13 +5840,17 @@ static void post_kvm_run_save(struct kvm_vcpu *vcpu)
kvm_run->flags = is_smm(vcpu) ? KVM_RUN_X86_SMM : 0;
kvm_run->cr8 = kvm_get_cr8(vcpu);
kvm_run->apic_base = kvm_get_apic_base(vcpu);
- if (irqchip_in_kernel(vcpu->kvm))
- kvm_run->ready_for_interrupt_injection = 1;
- else
+ if (!irqchip_in_kernel(vcpu->kvm))
kvm_run->ready_for_interrupt_injection =
kvm_arch_interrupt_allowed(vcpu) &&
!kvm_cpu_has_interrupt(vcpu) &&
!kvm_event_needs_reinjection(vcpu);
+ else if (!pic_in_kernel(vcpu->kvm))
+ kvm_run->ready_for_interrupt_injection =
+ kvm_apic_accept_pic_intr(vcpu) &&
+ !kvm_cpu_has_interrupt(vcpu);
+ else
+ kvm_run->ready_for_interrupt_injection = 1;
}
static void update_cr8_intercept(struct kvm_vcpu *vcpu)
@@ -7409,6 +7431,8 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
kvm_async_pf_hash_reset(vcpu);
kvm_pmu_init(vcpu);
+ vcpu->arch.pending_external_vector = -1;
+
return 0;
fail_free_mce_banks:
--
1.8.3.1
^ permalink raw reply related [flat|nested] 17+ messages in thread