From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH v2 4/4] kvm tools: Use ioeventfd in virtio-rng Date: Fri, 27 May 2011 19:18:40 +0300 Message-ID: <1306513120-28794-4-git-send-email-levinsasha928@gmail.com> References: <1306513120-28794-1-git-send-email-levinsasha928@gmail.com> Cc: john@jfloren.net, kvm@vger.kernel.org, mingo@elte.hu, asias.hejun@gmail.com, gorcunov@gmail.com, prasadjoshi124@gmail.com, Sasha Levin To: penberg@kernel.org Return-path: Received: from mail-ww0-f44.google.com ([74.125.82.44]:51264 "EHLO mail-ww0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754050Ab1E0QUU (ORCPT ); Fri, 27 May 2011 12:20:20 -0400 Received: by mail-ww0-f44.google.com with SMTP id 36so2028484wwa.1 for ; Fri, 27 May 2011 09:20:19 -0700 (PDT) In-Reply-To: <1306513120-28794-1-git-send-email-levinsasha928@gmail.com> Sender: kvm-owner@vger.kernel.org List-ID: Use ioeventfds to receive notifications of IO events in virtio-rng. Doing so prevents an exit every time we need to supply randomness to the guest. Signed-off-by: Sasha Levin --- tools/kvm/virtio/rng.c | 27 ++++++++++++++++++++++++++- 1 files changed, 26 insertions(+), 1 deletions(-) diff --git a/tools/kvm/virtio/rng.c b/tools/kvm/virtio/rng.c index 1a3bda3..d5d7795c 100644 --- a/tools/kvm/virtio/rng.c +++ b/tools/kvm/virtio/rng.c @@ -10,6 +10,7 @@ #include "kvm/pci.h" #include "kvm/threadpool.h" #include "kvm/irq.h" +#include "kvm/ioeventfd.h" #include #include @@ -154,6 +155,7 @@ static bool virtio_rng_pci_io_out(struct ioport *ioport, struct kvm *kvm, u16 po break; case VIRTIO_PCI_QUEUE_NOTIFY: { u16 queue_index; + printf("regular exit"); queue_index = ioport__read16(data); thread_pool__do_job(rdev->jobs[queue_index].job_id); break; @@ -177,11 +179,19 @@ static struct ioport_operations virtio_rng_io_ops = { .io_out = virtio_rng_pci_io_out, }; +static void ioevent_callback(struct kvm *kvm, void *param) +{ + struct rng_dev_job *job = param; + + thread_pool__do_job(job->job_id); +} + void virtio_rng__init(struct kvm *kvm) { - u8 pin, line, dev; + u8 pin, line, dev, i; u16 rdev_base_addr; struct rng_dev *rdev; + struct ioevent ioevent; rdev = malloc(sizeof(*rdev)); if (rdev == NULL) @@ -213,6 +223,20 @@ void virtio_rng__init(struct kvm *kvm) pci__register(&rdev->pci_hdr, dev); list_add_tail(&rdev->list, &rdevs); + + for (i = 0; i < NUM_VIRT_QUEUES; i++) { + ioevent = (struct ioevent) { + .io_addr = rdev_base_addr + VIRTIO_PCI_QUEUE_NOTIFY, + .io_len = sizeof(u16), + .fn = ioevent_callback, + .fn_ptr = &rdev->jobs[i], + .datamatch = i, + .fn_kvm = kvm, + .fd = eventfd(0, 0), + }; + + ioeventfd__add_event(&ioevent); + } } void virtio_rng__delete_all(struct kvm *kvm) @@ -222,6 +246,7 @@ void virtio_rng__delete_all(struct kvm *kvm) rdev = list_first_entry(&rdevs, struct rng_dev, list); list_del(&rdev->list); + ioeventfd__del_event(rdev->base_addr + VIRTIO_PCI_QUEUE_NOTIFY, 0); free(rdev); } } -- 1.7.5.rc3