Use ioeventfds to receive notifications of IO events in virtio-blk. Doing so prevents an exit every time we read/write from/to the virtio disk.
Signed-off-by: Sasha Levin <[email protected]> --- tools/kvm/virtio/blk.c | 26 +++++++++++++++++++++++++- 1 files changed, 25 insertions(+), 1 deletions(-) diff --git a/tools/kvm/virtio/blk.c b/tools/kvm/virtio/blk.c index a8f9d8c..8d54f5a 100644 --- a/tools/kvm/virtio/blk.c +++ b/tools/kvm/virtio/blk.c @@ -10,6 +10,7 @@ #include "kvm/kvm.h" #include "kvm/pci.h" #include "kvm/threadpool.h" +#include "kvm/ioeventfd.h" #include <linux/virtio_ring.h> #include <linux/virtio_blk.h> @@ -243,11 +244,19 @@ static struct ioport_operations virtio_blk_io_ops = { .io_out = virtio_blk_pci_io_out, }; +static void ioevent_callback(struct kvm *kvm, void *param) +{ + struct blk_dev_job *job = param; + + thread_pool__do_job(job->job_id); +} + void virtio_blk__init(struct kvm *kvm, struct disk_image *disk) { u16 blk_dev_base_addr; - u8 dev, pin, line; + u8 dev, pin, line, i; struct blk_dev *bdev; + struct ioevent ioevent; if (!disk) return; @@ -293,6 +302,20 @@ void virtio_blk__init(struct kvm *kvm, struct disk_image *disk) bdev->pci_hdr.irq_line = line; pci__register(&bdev->pci_hdr, dev); + + for (i = 0; i < NUM_VIRT_QUEUES; i++) { + ioevent = (struct ioevent) { + .io_addr = blk_dev_base_addr + VIRTIO_PCI_QUEUE_NOTIFY, + .io_len = sizeof(u16), + .fn = ioevent_callback, + .datamatch = i, + .fn_ptr = &bdev->jobs[i], + .fn_kvm = kvm, + .fd = eventfd(0, 0), + }; + + ioeventfd__add_event(&ioevent); + } } void virtio_blk__init_all(struct kvm *kvm) @@ -309,6 +332,7 @@ void virtio_blk__delete_all(struct kvm *kvm) struct blk_dev *bdev; bdev = list_first_entry(&bdevs, struct blk_dev, list); + ioeventfd__del_event(bdev->base_addr + VIRTIO_PCI_QUEUE_NOTIFY, 0); list_del(&bdev->list); free(bdev); } -- 1.7.5.rc3 -- 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
