[PATCH 0/3] KVM: x86: Clean up lowest priority IRQ code

[PATCH 0/3] KVM: x86: Clean up lowest priority IRQ code

[Sean Christopherson]

Move some local APIC specific code into lapic.c that has no business being
exposed outside of local APIC emulation.   The lowest priority vector
hashing code in particular is *very* specific to lapic.c internals, but
that's not at all obvious from the globally-visible symbols.

Sean Christopherson (3):
  KVM: x86: Move kvm_irq_delivery_to_apic() from irq.c to lapic.c
  KVM: x86: Make "lowest priority" helpers local to lapic.c
  KVM: x86: Move vector_hashing into lapic.c

 arch/x86/kvm/irq.c   | 57 ------------------------------
 arch/x86/kvm/irq.h   |  4 ---
 arch/x86/kvm/lapic.c | 82 +++++++++++++++++++++++++++++++++++++++-----
 arch/x86/kvm/lapic.h | 12 ++-----
 arch/x86/kvm/x86.c   |  8 -----
 arch/x86/kvm/x86.h   |  1 -
 6 files changed, 77 insertions(+), 87 deletions(-)


base-commit: 9c7a1f8d8784e17bb6e0df4f616fbd8daae02919
-- 
2.51.0.261.g7ce5a0a67e-goog

[PATCH 1/3] KVM: x86: Move kvm_irq_delivery_to_apic() from irq.c to lapic.c

[Sean Christopherson]

Move kvm_irq_delivery_to_apic() to lapic.c as it is specific to local APIC
emulation.  This will allow burying more local APIC code in lapic.c, e.g.
the various "lowest priority" helpers.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/irq.c   | 57 --------------------------------------------
 arch/x86/kvm/irq.h   |  4 ----
 arch/x86/kvm/lapic.c | 57 ++++++++++++++++++++++++++++++++++++++++++++
 arch/x86/kvm/lapic.h |  3 +++
 4 files changed, 60 insertions(+), 61 deletions(-)

diff --git a/arch/x86/kvm/irq.c b/arch/x86/kvm/irq.c
index 16da89259011..a6b122f732be 100644
--- a/arch/x86/kvm/irq.c
+++ b/arch/x86/kvm/irq.c
@@ -195,63 +195,6 @@ bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
 	return irqchip_in_kernel(kvm);
 }
 
-int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
-			     struct kvm_lapic_irq *irq, struct dest_map *dest_map)
-{
-	int r = -1;
-	struct kvm_vcpu *vcpu, *lowest = NULL;
-	unsigned long i, dest_vcpu_bitmap[BITS_TO_LONGS(KVM_MAX_VCPUS)];
-	unsigned int dest_vcpus = 0;
-
-	if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map))
-		return r;
-
-	if (irq->dest_mode == APIC_DEST_PHYSICAL &&
-	    irq->dest_id == 0xff && kvm_lowest_prio_delivery(irq)) {
-		pr_info("apic: phys broadcast and lowest prio\n");
-		irq->delivery_mode = APIC_DM_FIXED;
-	}
-
-	memset(dest_vcpu_bitmap, 0, sizeof(dest_vcpu_bitmap));
-
-	kvm_for_each_vcpu(i, vcpu, kvm) {
-		if (!kvm_apic_present(vcpu))
-			continue;
-
-		if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
-					irq->dest_id, irq->dest_mode))
-			continue;
-
-		if (!kvm_lowest_prio_delivery(irq)) {
-			if (r < 0)
-				r = 0;
-			r += kvm_apic_set_irq(vcpu, irq, dest_map);
-		} else if (kvm_apic_sw_enabled(vcpu->arch.apic)) {
-			if (!kvm_vector_hashing_enabled()) {
-				if (!lowest)
-					lowest = vcpu;
-				else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
-					lowest = vcpu;
-			} else {
-				__set_bit(i, dest_vcpu_bitmap);
-				dest_vcpus++;
-			}
-		}
-	}
-
-	if (dest_vcpus != 0) {
-		int idx = kvm_vector_to_index(irq->vector, dest_vcpus,
-					dest_vcpu_bitmap, KVM_MAX_VCPUS);
-
-		lowest = kvm_get_vcpu(kvm, idx);
-	}
-
-	if (lowest)
-		r = kvm_apic_set_irq(lowest, irq, dest_map);
-
-	return r;
-}
-
 static void kvm_msi_to_lapic_irq(struct kvm *kvm,
 				 struct kvm_kernel_irq_routing_entry *e,
 				 struct kvm_lapic_irq *irq)
diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index 5e62c1f79ce6..34f4a78a7a01 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -121,8 +121,4 @@ void __kvm_migrate_timers(struct kvm_vcpu *vcpu);
 
 int apic_has_pending_timer(struct kvm_vcpu *vcpu);
 
-int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
-			     struct kvm_lapic_irq *irq,
-			     struct dest_map *dest_map);
-
 #endif
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index ed636c1f5e58..129ade22efca 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1251,6 +1251,63 @@ bool kvm_intr_is_single_vcpu_fast(struct kvm *kvm, struct kvm_lapic_irq *irq,
 	return ret;
 }
 
+int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
+			     struct kvm_lapic_irq *irq, struct dest_map *dest_map)
+{
+	int r = -1;
+	struct kvm_vcpu *vcpu, *lowest = NULL;
+	unsigned long i, dest_vcpu_bitmap[BITS_TO_LONGS(KVM_MAX_VCPUS)];
+	unsigned int dest_vcpus = 0;
+
+	if (kvm_irq_delivery_to_apic_fast(kvm, src, irq, &r, dest_map))
+		return r;
+
+	if (irq->dest_mode == APIC_DEST_PHYSICAL &&
+	    irq->dest_id == 0xff && kvm_lowest_prio_delivery(irq)) {
+		pr_info("apic: phys broadcast and lowest prio\n");
+		irq->delivery_mode = APIC_DM_FIXED;
+	}
+
+	memset(dest_vcpu_bitmap, 0, sizeof(dest_vcpu_bitmap));
+
+	kvm_for_each_vcpu(i, vcpu, kvm) {
+		if (!kvm_apic_present(vcpu))
+			continue;
+
+		if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
+					irq->dest_id, irq->dest_mode))
+			continue;
+
+		if (!kvm_lowest_prio_delivery(irq)) {
+			if (r < 0)
+				r = 0;
+			r += kvm_apic_set_irq(vcpu, irq, dest_map);
+		} else if (kvm_apic_sw_enabled(vcpu->arch.apic)) {
+			if (!kvm_vector_hashing_enabled()) {
+				if (!lowest)
+					lowest = vcpu;
+				else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
+					lowest = vcpu;
+			} else {
+				__set_bit(i, dest_vcpu_bitmap);
+				dest_vcpus++;
+			}
+		}
+	}
+
+	if (dest_vcpus != 0) {
+		int idx = kvm_vector_to_index(irq->vector, dest_vcpus,
+					dest_vcpu_bitmap, KVM_MAX_VCPUS);
+
+		lowest = kvm_get_vcpu(kvm, idx);
+	}
+
+	if (lowest)
+		r = kvm_apic_set_irq(lowest, irq, dest_map);
+
+	return r;
+}
+
 /*
  * Add a pending IRQ into lapic.
  * Return 1 if successfully added and 0 if discarded.
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index 8b00e29741de..edfed763cf89 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -119,6 +119,9 @@ void kvm_inhibit_apic_access_page(struct kvm_vcpu *vcpu);
 
 bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
 		struct kvm_lapic_irq *irq, int *r, struct dest_map *dest_map);
+int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
+			     struct kvm_lapic_irq *irq,
+			     struct dest_map *dest_map);
 void kvm_apic_send_ipi(struct kvm_lapic *apic, u32 icr_low, u32 icr_high);
 
 int kvm_apic_set_base(struct kvm_vcpu *vcpu, u64 value, bool host_initiated);
-- 
2.51.0.261.g7ce5a0a67e-goog

[PATCH 2/3] KVM: x86: Make "lowest priority" helpers local to lapic.c

[Sean Christopherson]

Make various helpers for resolving lowest priority IRQs local to lapic.c
now that kvm_irq_delivery_to_apic() lives in lapic.c as well.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/lapic.c | 19 ++++++++++++-------
 arch/x86/kvm/lapic.h |  9 ---------
 2 files changed, 12 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 129ade22efca..1a8bc81973e3 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1063,8 +1063,8 @@ bool kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
 }
 EXPORT_SYMBOL_GPL(kvm_apic_match_dest);
 
-int kvm_vector_to_index(u32 vector, u32 dest_vcpus,
-		       const unsigned long *bitmap, u32 bitmap_size)
+static int kvm_vector_to_index(u32 vector, u32 dest_vcpus,
+			       const unsigned long *bitmap, u32 bitmap_size)
 {
 	int idx = find_nth_bit(bitmap, bitmap_size, vector % dest_vcpus);
 
@@ -1099,6 +1099,16 @@ static bool kvm_apic_is_broadcast_dest(struct kvm *kvm, struct kvm_lapic **src,
 	return false;
 }
 
+static bool kvm_lowest_prio_delivery(struct kvm_lapic_irq *irq)
+{
+	return (irq->delivery_mode == APIC_DM_LOWEST || irq->msi_redir_hint);
+}
+
+static int kvm_apic_compare_prio(struct kvm_vcpu *vcpu1, struct kvm_vcpu *vcpu2)
+{
+	return vcpu1->arch.apic_arb_prio - vcpu2->arch.apic_arb_prio;
+}
+
 /* Return true if the interrupt can be handled by using *bitmap as index mask
  * for valid destinations in *dst array.
  * Return false if kvm_apic_map_get_dest_lapic did nothing useful.
@@ -1451,11 +1461,6 @@ void kvm_bitmap_or_dest_vcpus(struct kvm *kvm, struct kvm_lapic_irq *irq,
 	rcu_read_unlock();
 }
 
-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, apic->vcpu->arch.ioapic_handled_vectors);
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index edfed763cf89..50123fe7f58f 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -105,7 +105,6 @@ void kvm_apic_set_version(struct kvm_vcpu *vcpu);
 void kvm_apic_after_set_mcg_cap(struct kvm_vcpu *vcpu);
 bool kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
 			   int shorthand, unsigned int dest, int dest_mode);
-int kvm_apic_compare_prio(struct kvm_vcpu *vcpu1, struct kvm_vcpu *vcpu2);
 void kvm_apic_clear_irr(struct kvm_vcpu *vcpu, int vec);
 bool __kvm_apic_update_irr(unsigned long *pir, void *regs, int *max_irr);
 bool kvm_apic_update_irr(struct kvm_vcpu *vcpu, unsigned long *pir, int *max_irr);
@@ -225,12 +224,6 @@ static inline bool kvm_apic_init_sipi_allowed(struct kvm_vcpu *vcpu)
 	       !kvm_x86_call(apic_init_signal_blocked)(vcpu);
 }
 
-static inline bool kvm_lowest_prio_delivery(struct kvm_lapic_irq *irq)
-{
-	return (irq->delivery_mode == APIC_DM_LOWEST ||
-			irq->msi_redir_hint);
-}
-
 static inline int kvm_lapic_latched_init(struct kvm_vcpu *vcpu)
 {
 	return lapic_in_kernel(vcpu) && test_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
@@ -245,8 +238,6 @@ void kvm_bitmap_or_dest_vcpus(struct kvm *kvm, struct kvm_lapic_irq *irq,
 
 bool kvm_intr_is_single_vcpu_fast(struct kvm *kvm, struct kvm_lapic_irq *irq,
 			struct kvm_vcpu **dest_vcpu);
-int kvm_vector_to_index(u32 vector, u32 dest_vcpus,
-			const unsigned long *bitmap, u32 bitmap_size);
 void kvm_lapic_switch_to_sw_timer(struct kvm_vcpu *vcpu);
 void kvm_lapic_switch_to_hv_timer(struct kvm_vcpu *vcpu);
 void kvm_lapic_expired_hv_timer(struct kvm_vcpu *vcpu);
-- 
2.51.0.261.g7ce5a0a67e-goog

[PATCH 3/3] KVM: x86: Move vector_hashing into lapic.c

[Sean Christopherson]

Move the vector_hashing module param into lapic.c now that all usage is
contained within the local APIC emulation code.

Opportunistically drop the accessor and append "_enabled" to the variable
to help capture that it's a boolean module param.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/lapic.c | 8 ++++++--
 arch/x86/kvm/x86.c   | 8 --------
 arch/x86/kvm/x86.h   | 1 -
 3 files changed, 6 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 1a8bc81973e3..6fac6fb86c19 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -74,6 +74,10 @@ module_param(lapic_timer_advance, bool, 0444);
 #define LAPIC_TIMER_ADVANCE_NS_MAX     5000
 /* step-by-step approximation to mitigate fluctuation */
 #define LAPIC_TIMER_ADVANCE_ADJUST_STEP 8
+
+static bool __read_mostly vector_hashing_enabled = true;
+module_param_named(vector_hashing, vector_hashing_enabled, bool, 0444);
+
 static int kvm_lapic_msr_read(struct kvm_lapic *apic, u32 reg, u64 *data);
 static int kvm_lapic_msr_write(struct kvm_lapic *apic, u32 reg, u64 data);
 
@@ -1152,7 +1156,7 @@ static inline bool kvm_apic_map_get_dest_lapic(struct kvm *kvm,
 	if (!kvm_lowest_prio_delivery(irq))
 		return true;
 
-	if (!kvm_vector_hashing_enabled()) {
+	if (!vector_hashing_enabled) {
 		lowest = -1;
 		for_each_set_bit(i, bitmap, 16) {
 			if (!(*dst)[i])
@@ -1293,7 +1297,7 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
 				r = 0;
 			r += kvm_apic_set_irq(vcpu, irq, dest_map);
 		} else if (kvm_apic_sw_enabled(vcpu->arch.apic)) {
-			if (!kvm_vector_hashing_enabled()) {
+			if (!vector_hashing_enabled) {
 				if (!lowest)
 					lowest = vcpu;
 				else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 7ba2cdfdac44..554b36de700c 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -164,9 +164,6 @@ module_param(kvmclock_periodic_sync, bool, 0444);
 static u32 __read_mostly tsc_tolerance_ppm = 250;
 module_param(tsc_tolerance_ppm, uint, 0644);
 
-static bool __read_mostly vector_hashing = true;
-module_param(vector_hashing, bool, 0444);
-
 bool __read_mostly enable_vmware_backdoor = false;
 module_param(enable_vmware_backdoor, bool, 0444);
 EXPORT_SYMBOL_GPL(enable_vmware_backdoor);
@@ -13552,11 +13549,6 @@ bool kvm_arch_has_noncoherent_dma(struct kvm *kvm)
 }
 EXPORT_SYMBOL_GPL(kvm_arch_has_noncoherent_dma);
 
-bool kvm_vector_hashing_enabled(void)
-{
-	return vector_hashing;
-}
-
 bool kvm_arch_no_poll(struct kvm_vcpu *vcpu)
 {
 	return (vcpu->arch.msr_kvm_poll_control & 1) == 0;
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index eb3088684e8a..786e36fcd0fb 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -431,7 +431,6 @@ void kvm_deliver_exception_payload(struct kvm_vcpu *vcpu,
 
 int kvm_mtrr_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data);
 int kvm_mtrr_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata);
-bool kvm_vector_hashing_enabled(void);
 void kvm_fixup_and_inject_pf_error(struct kvm_vcpu *vcpu, gva_t gva, u16 error_code);
 int x86_decode_emulated_instruction(struct kvm_vcpu *vcpu, int emulation_type,
 				    void *insn, int insn_len);
-- 
2.51.0.261.g7ce5a0a67e-goog