[PATCH 5/5] KVM: bit ops for deliver_bitmap

Sheng Yang
2009-02-25T09:19:05Z

It's also convenient when we extend KVM supported vcpu number in the future.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
---
arch/x86/kvm/lapic.c | 7 ++++---
virt/kvm/ioapic.c | 25 ++++++++++++++-----------
virt/kvm/irq_comm.c | 21 ++++++++++++---------
3 files changed, 30 insertions(+), 23 deletions(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 6aa8d20..735f80a 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -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);
diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
index 9472031..f80ec08 100644
--- a/virt/kvm/ioapic.c
+++ b/virt/kvm/ioapic.c
@@ -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 = 0;

@@ -213,21 +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 << 0;
+ set_bit(0, deliver_bitmask);
+ else
#endif
- for (vcpu_id = 0; deliver_bitmask != 0; vcpu_id++) {
- if (!(deliver_bitmask & (1 << vcpu_id)))
- continue;
- deliver_bitmask &= ~(1 << vcpu_id);
+ 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 -1;
+ }
+
+ 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 ==
diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c
index 9411af1..9107142 100644
--- a/virt/kvm/irq_comm.c
+++ b/virt/kvm/irq_comm.c
@@ -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;
@@ -94,16 +96,17 @@ static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
(unsigned long *)&e->msi.data);

/* 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) {
- printk(KERN_WARNING "kvm: no destination for MSI delivery!");
+ 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)
r += kvm_apic_set_irq(vcpu, entry.fields.vector,
--
1.5.4.5