KVM: arm/arm64: Optimize away redundant LR tracking

[firefly-linux-kernel-4.4.55.git] / virt / kvm / arm / vgic.c

diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index d4669eb29b77f7a177371bd031621925488b8551..265a410357283a98fd1183929b803c694badf371 100644 (file)
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -108,6 +108,7 @@ static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu);
 static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu);
 static struct vgic_lr vgic_get_lr(const struct kvm_vcpu *vcpu, int lr);
 static void vgic_set_lr(struct kvm_vcpu *vcpu, int lr, struct vgic_lr lr_desc);
+static u64 vgic_get_elrsr(struct kvm_vcpu *vcpu);
 static struct irq_phys_map *vgic_irq_map_search(struct kvm_vcpu *vcpu,
                                                int virt_irq);
 static int compute_pending_for_cpu(struct kvm_vcpu *vcpu);
@@ -691,9 +692,11 @@ bool vgic_handle_cfg_reg(u32 *reg, struct kvm_exit_mmio *mmio,
 void vgic_unqueue_irqs(struct kvm_vcpu *vcpu)
 {
        struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
+       u64 elrsr = vgic_get_elrsr(vcpu);
+       unsigned long *elrsr_ptr = u64_to_bitmask(&elrsr);
        int i;
 
-       for_each_set_bit(i, vgic_cpu->lr_used, vgic_cpu->nr_lr) {
+       for_each_clear_bit(i, elrsr_ptr, vgic_cpu->nr_lr) {
                struct vgic_lr lr = vgic_get_lr(vcpu, i);
 
                /*
@@ -1098,7 +1101,6 @@ static inline void vgic_enable(struct kvm_vcpu *vcpu)
 
 static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu)
 {
-       struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
        struct vgic_lr vlr = vgic_get_lr(vcpu, lr_nr);
 
        /*
@@ -1112,8 +1114,6 @@ static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu)
 
        vlr.state = 0;
        vgic_set_lr(vcpu, lr_nr, vlr);
-       clear_bit(lr_nr, vgic_cpu->lr_used);
-       vgic_cpu->vgic_irq_lr_map[irq] = LR_EMPTY;
        vgic_sync_lr_elrsr(vcpu, lr_nr, vlr);
 }
 
@@ -1128,10 +1128,11 @@ static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu)
  */
 static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu)
 {
-       struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
+       u64 elrsr = vgic_get_elrsr(vcpu);
+       unsigned long *elrsr_ptr = u64_to_bitmask(&elrsr);
        int lr;
 
-       for_each_set_bit(lr, vgic_cpu->lr_used, vgic->nr_lr) {
+       for_each_clear_bit(lr, elrsr_ptr, vgic->nr_lr) {
                struct vgic_lr vlr = vgic_get_lr(vcpu, lr);
 
                if (!vgic_irq_is_enabled(vcpu, vlr.irq)) {
@@ -1188,8 +1189,9 @@ static void vgic_queue_irq_to_lr(struct kvm_vcpu *vcpu, int irq,
  */
 bool vgic_queue_irq(struct kvm_vcpu *vcpu, u8 sgi_source_id, int irq)
 {
-       struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
        struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+       u64 elrsr = vgic_get_elrsr(vcpu);
+       unsigned long *elrsr_ptr = u64_to_bitmask(&elrsr);
        struct vgic_lr vlr;
        int lr;
 
@@ -1200,28 +1202,22 @@ bool vgic_queue_irq(struct kvm_vcpu *vcpu, u8 sgi_source_id, int irq)
 
        kvm_debug("Queue IRQ%d\n", irq);
 
-       lr = vgic_cpu->vgic_irq_lr_map[irq];
-
        /* Do we have an active interrupt for the same CPUID? */
-       if (lr != LR_EMPTY) {
+       for_each_clear_bit(lr, elrsr_ptr, vgic->nr_lr) {
                vlr = vgic_get_lr(vcpu, lr);
-               if (vlr.source == sgi_source_id) {
+               if (vlr.irq == irq && vlr.source == sgi_source_id) {
                        kvm_debug("LR%d piggyback for IRQ%d\n", lr, vlr.irq);
-                       BUG_ON(!test_bit(lr, vgic_cpu->lr_used));
                        vgic_queue_irq_to_lr(vcpu, irq, lr, vlr);
                        return true;
                }
        }
 
        /* Try to use another LR for this interrupt */
-       lr = find_first_zero_bit((unsigned long *)vgic_cpu->lr_used,
-                              vgic->nr_lr);
+       lr = find_first_bit(elrsr_ptr, vgic->nr_lr);
        if (lr >= vgic->nr_lr)
                return false;
 
        kvm_debug("LR%d allocated for IRQ%d %x\n", lr, irq, sgi_source_id);
-       vgic_cpu->vgic_irq_lr_map[irq] = lr;
-       set_bit(lr, vgic_cpu->lr_used);
 
        vlr.irq = irq;
        vlr.source = sgi_source_id;
@@ -1456,7 +1452,6 @@ static bool vgic_sync_hwirq(struct kvm_vcpu *vcpu, int lr, struct vgic_lr vlr)
 /* Sync back the VGIC state after a guest run */
 static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
 {
-       struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
        struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
        u64 elrsr;
        unsigned long *elrsr_ptr;
@@ -1469,22 +1464,10 @@ static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
 
        /* Deal with HW interrupts, and clear mappings for empty LRs */
        for (lr = 0; lr < vgic->nr_lr; lr++) {
-               struct vgic_lr vlr;
-
-               if (!test_bit(lr, vgic_cpu->lr_used))
-                       continue;
-
-               vlr = vgic_get_lr(vcpu, lr);
-               if (vgic_sync_hwirq(vcpu, lr, vlr))
-                       level_pending = true;
-
-               if (!test_bit(lr, elrsr_ptr))
-                       continue;
-
-               clear_bit(lr, vgic_cpu->lr_used);
+               struct vgic_lr vlr = vgic_get_lr(vcpu, lr);
 
+               level_pending |= vgic_sync_hwirq(vcpu, lr, vlr);
                BUG_ON(vlr.irq >= dist->nr_irqs);
-               vgic_cpu->vgic_irq_lr_map[vlr.irq] = LR_EMPTY;
        }
 
        /* Check if we still have something up our sleeve... */
@@ -1912,12 +1895,10 @@ void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu)
        kfree(vgic_cpu->pending_shared);
        kfree(vgic_cpu->active_shared);
        kfree(vgic_cpu->pend_act_shared);
-       kfree(vgic_cpu->vgic_irq_lr_map);
        vgic_destroy_irq_phys_map(vcpu->kvm, &vgic_cpu->irq_phys_map_list);
        vgic_cpu->pending_shared = NULL;
        vgic_cpu->active_shared = NULL;
        vgic_cpu->pend_act_shared = NULL;
-       vgic_cpu->vgic_irq_lr_map = NULL;
 }
 
 static int vgic_vcpu_init_maps(struct kvm_vcpu *vcpu, int nr_irqs)
@@ -1928,18 +1909,14 @@ static int vgic_vcpu_init_maps(struct kvm_vcpu *vcpu, int nr_irqs)
        vgic_cpu->pending_shared = kzalloc(sz, GFP_KERNEL);
        vgic_cpu->active_shared = kzalloc(sz, GFP_KERNEL);
        vgic_cpu->pend_act_shared = kzalloc(sz, GFP_KERNEL);
-       vgic_cpu->vgic_irq_lr_map = kmalloc(nr_irqs, GFP_KERNEL);
 
        if (!vgic_cpu->pending_shared
                || !vgic_cpu->active_shared
-               || !vgic_cpu->pend_act_shared
-               || !vgic_cpu->vgic_irq_lr_map) {
+               || !vgic_cpu->pend_act_shared) {
                kvm_vgic_vcpu_destroy(vcpu);
                return -ENOMEM;
        }
 
-       memset(vgic_cpu->vgic_irq_lr_map, LR_EMPTY, nr_irqs);
-
        /*
         * Store the number of LRs per vcpu, so we don't have to go
         * all the way to the distributor structure to find out. Only