KVM: x86: Move vector_hashing into lapic.c

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.

Link: https://lore.kernel.org/r/20250821214209.3463350-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Author: sean-jc

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);
 
@@ -1150,7 +1154,7 @@ 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])
@@ -1291,7 +1295,7 @@ 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)

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);
@@ -13549,11 +13546,6 @@ 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;

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);