From: Jan Kiszka <[email protected]> The complete work handler runs with assigned_dev_lock acquired and interrupts disabled, so there is nothing to gain pushing this work out of the actually IRQ handler. Fold them together.
Signed-off-by: Jan Kiszka <[email protected]> --- include/linux/kvm_host.h | 1 - virt/kvm/assigned-dev.c | 71 +++++++++++++++------------------------------- 2 files changed, 23 insertions(+), 49 deletions(-) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 462b982..df5497f 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -465,7 +465,6 @@ struct kvm_guest_msix_entry { struct kvm_assigned_dev_kernel { struct kvm_irq_ack_notifier ack_notifier; - struct work_struct interrupt_work; struct list_head list; int assigned_dev_id; int host_segnr; diff --git a/virt/kvm/assigned-dev.c b/virt/kvm/assigned-dev.c index 7c98928..5c1b56a 100644 --- a/virt/kvm/assigned-dev.c +++ b/virt/kvm/assigned-dev.c @@ -55,18 +55,24 @@ static int find_index_from_host_irq(struct kvm_assigned_dev_kernel return index; } -static void kvm_assigned_dev_interrupt_work_handler(struct work_struct *work) +static irqreturn_t kvm_assigned_dev_intr(int irq, void *dev_id) { - struct kvm_assigned_dev_kernel *assigned_dev; - int i; - - assigned_dev = container_of(work, struct kvm_assigned_dev_kernel, - interrupt_work); + struct kvm_assigned_dev_kernel *assigned_dev = + (struct kvm_assigned_dev_kernel *) dev_id; + unsigned long flags; - spin_lock_irq(&assigned_dev->assigned_dev_lock); + spin_lock_irqsave(&assigned_dev->assigned_dev_lock, flags); if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSIX) { struct kvm_guest_msix_entry *guest_entries = assigned_dev->guest_msix_entries; + int index = find_index_from_host_irq(assigned_dev, irq); + int i; + + if (index < 0) + goto out; + + guest_entries[index].flags |= KVM_ASSIGNED_MSIX_PENDING; + for (i = 0; i < assigned_dev->entries_nr; i++) { if (!(guest_entries[i].flags & KVM_ASSIGNED_MSIX_PENDING)) @@ -76,33 +82,15 @@ static void kvm_assigned_dev_interrupt_work_handler(struct work_struct *work) assigned_dev->irq_source_id, guest_entries[i].vector, 1); } - } else + } else { kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id, assigned_dev->guest_irq, 1); - spin_unlock_irq(&assigned_dev->assigned_dev_lock); -} - -static irqreturn_t kvm_assigned_dev_intr(int irq, void *dev_id) -{ - unsigned long flags; - struct kvm_assigned_dev_kernel *assigned_dev = - (struct kvm_assigned_dev_kernel *) dev_id; - - spin_lock_irqsave(&assigned_dev->assigned_dev_lock, flags); - if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSIX) { - int index = find_index_from_host_irq(assigned_dev, irq); - if (index < 0) - goto out; - assigned_dev->guest_msix_entries[index].flags |= - KVM_ASSIGNED_MSIX_PENDING; - } - - schedule_work(&assigned_dev->interrupt_work); - - if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_GUEST_INTX) { - disable_irq_nosync(irq); - assigned_dev->host_irq_disabled = true; + if (assigned_dev->irq_requested_type & + KVM_DEV_IRQ_GUEST_INTX) { + disable_irq_nosync(irq); + assigned_dev->host_irq_disabled = true; + } } out: @@ -147,33 +135,23 @@ static void deassign_guest_irq(struct kvm *kvm, assigned_dev->irq_requested_type &= ~(KVM_DEV_IRQ_GUEST_MASK); } -/* The function implicit hold kvm->lock mutex due to cancel_work_sync() */ static void deassign_host_irq(struct kvm *kvm, struct kvm_assigned_dev_kernel *assigned_dev) { /* - * In kvm_free_device_irq, cancel_work_sync return true if: - * 1. work is scheduled, and then cancelled. - * 2. work callback is executed. - * - * The first one ensured that the irq is disabled and no more events - * would happen. But for the second one, the irq may be enabled (e.g. - * for MSI). So we disable irq here to prevent further events. + * We disable irq here to prevent further events. * * Notice this maybe result in nested disable if the interrupt type is * INTx, but it's OK for we are going to free it. * * If this function is a part of VM destroy, please ensure that till * now, the kvm state is still legal for probably we also have to wait - * interrupt_work done. + * on a currently running IRQ handler. */ if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSIX) { int i; for (i = 0; i < assigned_dev->entries_nr; i++) - disable_irq_nosync(assigned_dev-> - host_msix_entries[i].vector); - - cancel_work_sync(&assigned_dev->interrupt_work); + disable_irq(assigned_dev->host_msix_entries[i].vector); for (i = 0; i < assigned_dev->entries_nr; i++) free_irq(assigned_dev->host_msix_entries[i].vector, @@ -185,8 +163,7 @@ static void deassign_host_irq(struct kvm *kvm, pci_disable_msix(assigned_dev->dev); } else { /* Deal with MSI and INTx */ - disable_irq_nosync(assigned_dev->host_irq); - cancel_work_sync(&assigned_dev->interrupt_work); + disable_irq(assigned_dev->host_irq); free_irq(assigned_dev->host_irq, (void *)assigned_dev); @@ -558,8 +535,6 @@ static int kvm_vm_ioctl_assign_device(struct kvm *kvm, match->irq_source_id = -1; match->kvm = kvm; match->ack_notifier.irq_acked = kvm_assigned_dev_ack_irq; - INIT_WORK(&match->interrupt_work, - kvm_assigned_dev_interrupt_work_handler); list_add(&match->list, &kvm->arch.assigned_dev_head); -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
