KVM: bit ops for deliver_bitmap
Sheng Yang [Wed, 11 Feb 2009 08:03:40 +0000 (16:03 +0800)]
It's also convenient when we extend KVM supported vcpu number in the future.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/kvm/lapic.c
virt/kvm/ioapic.c
virt/kvm/irq_comm.c

index 6aa8d20..afc59b2 100644 (file)
@@ -483,9 +483,10 @@ static void apic_send_ipi(struct kvm_lapic *apic)
 
        struct kvm_vcpu *target;
        struct kvm_vcpu *vcpu;
-       unsigned long lpr_map = 0;
+       DECLARE_BITMAP(lpr_map, KVM_MAX_VCPUS);
        int i;
 
+       bitmap_zero(lpr_map, KVM_MAX_VCPUS);
        apic_debug("icr_high 0x%x, icr_low 0x%x, "
                   "short_hand 0x%x, dest 0x%x, trig_mode 0x%x, level 0x%x, "
                   "dest_mode 0x%x, delivery_mode 0x%x, vector 0x%x\n",
@@ -500,7 +501,7 @@ static void apic_send_ipi(struct kvm_lapic *apic)
                if (vcpu->arch.apic &&
                    apic_match_dest(vcpu, apic, short_hand, dest, dest_mode)) {
                        if (delivery_mode == APIC_DM_LOWEST)
-                               set_bit(vcpu->vcpu_id, &lpr_map);
+                               __set_bit(vcpu->vcpu_id, lpr_map);
                        else
                                __apic_accept_irq(vcpu->arch.apic, delivery_mode,
                                                  vector, level, trig_mode);
@@ -508,7 +509,7 @@ static void apic_send_ipi(struct kvm_lapic *apic)
        }
 
        if (delivery_mode == APIC_DM_LOWEST) {
-               target = kvm_get_lowest_prio_vcpu(vcpu->kvm, vector, &lpr_map);
+               target = kvm_get_lowest_prio_vcpu(vcpu->kvm, vector, lpr_map);
                if (target != NULL)
                        __apic_accept_irq(target->arch.apic, delivery_mode,
                                          vector, level, trig_mode);
index 3b53712..7c2cb2b 100644 (file)
@@ -203,7 +203,7 @@ void kvm_ioapic_get_delivery_bitmask(struct kvm_ioapic *ioapic, u8 dest,
 static int ioapic_deliver(struct kvm_ioapic *ioapic, int irq)
 {
        union kvm_ioapic_redirect_entry entry = ioapic->redirtbl[irq];
-       unsigned long deliver_bitmask;
+       DECLARE_BITMAP(deliver_bitmask, KVM_MAX_VCPUS);
        struct kvm_vcpu *vcpu;
        int vcpu_id, r = -1;
 
@@ -213,22 +213,24 @@ static int ioapic_deliver(struct kvm_ioapic *ioapic, int irq)
                     entry.fields.delivery_mode, entry.fields.vector,
                     entry.fields.trig_mode);
 
-       kvm_get_intr_delivery_bitmask(ioapic, &entry, &deliver_bitmask);
-       if (!deliver_bitmask) {
-               ioapic_debug("no target on destination\n");
-               return 0;
-       }
+       bitmap_zero(deliver_bitmask, KVM_MAX_VCPUS);
 
        /* Always delivery PIT interrupt to vcpu 0 */
 #ifdef CONFIG_X86
        if (irq == 0)
-               deliver_bitmask = 1;
+               __set_bit(0, deliver_bitmask);
+       else
 #endif
+               kvm_get_intr_delivery_bitmask(ioapic, &entry, deliver_bitmask);
+
+       if (find_first_bit(deliver_bitmask, KVM_MAX_VCPUS) >= KVM_MAX_VCPUS) {
+               ioapic_debug("no target on destination\n");
+               return 0;
+       }
 
-       for (vcpu_id = 0; deliver_bitmask != 0; vcpu_id++) {
-               if (!(deliver_bitmask & (1 << vcpu_id)))
-                       continue;
-               deliver_bitmask &= ~(1 << vcpu_id);
+       while ((vcpu_id = find_first_bit(deliver_bitmask, KVM_MAX_VCPUS))
+                       < KVM_MAX_VCPUS) {
+               __clear_bit(vcpu_id, deliver_bitmask);
                vcpu = ioapic->kvm->vcpus[vcpu_id];
                if (vcpu) {
                        if (entry.fields.delivery_mode ==
index d4421cd..d165e05 100644 (file)
@@ -56,7 +56,7 @@ void kvm_get_intr_delivery_bitmask(struct kvm_ioapic *ioapic,
        case IOAPIC_LOWEST_PRIORITY:
                vcpu = kvm_get_lowest_prio_vcpu(ioapic->kvm,
                                entry->fields.vector, deliver_bitmask);
-               *deliver_bitmask = 1 << vcpu->vcpu_id;
+               __set_bit(vcpu->vcpu_id, deliver_bitmask);
                break;
        case IOAPIC_FIXED:
        case IOAPIC_NMI:
@@ -76,10 +76,12 @@ static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
        struct kvm_vcpu *vcpu;
        struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
        union kvm_ioapic_redirect_entry entry;
-       unsigned long deliver_bitmask;
+       DECLARE_BITMAP(deliver_bitmask, KVM_MAX_VCPUS);
 
        BUG_ON(!ioapic);
 
+       bitmap_zero(deliver_bitmask, KVM_MAX_VCPUS);
+
        entry.bits = 0;
        entry.fields.dest_id = (e->msi.address_lo &
                        MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;
@@ -95,16 +97,15 @@ static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
 
        /* TODO Deal with RH bit of MSI message address */
 
-       kvm_get_intr_delivery_bitmask(ioapic, &entry, &deliver_bitmask);
+       kvm_get_intr_delivery_bitmask(ioapic, &entry, deliver_bitmask);
 
-       if (!deliver_bitmask) {
+       if (find_first_bit(deliver_bitmask, KVM_MAX_VCPUS) >= KVM_MAX_VCPUS) {
                printk(KERN_WARNING "kvm: no destination for MSI delivery!");
                return -1;
        }
-       for (vcpu_id = 0; deliver_bitmask != 0; vcpu_id++) {
-               if (!(deliver_bitmask & (1 << vcpu_id)))
-                       continue;
-               deliver_bitmask &= ~(1 << vcpu_id);
+       while ((vcpu_id = find_first_bit(deliver_bitmask,
+                                       KVM_MAX_VCPUS)) < KVM_MAX_VCPUS) {
+               __clear_bit(vcpu_id, deliver_bitmask);
                vcpu = ioapic->kvm->vcpus[vcpu_id];
                if (vcpu) {
                        if (r < 0)