[dpdk-dev,v3] vhost: Fix default value of kickfd and callfd
Commit Message
Currently, default values of kickfd and callfd are -1.
If the values are -1, current code guesses kickfd and callfd haven't
been initialized yet. Then vhost library will guess the virtqueue isn't
ready for processing.
But callfd and kickfd will be set as -1 when "--enable-kvm"
isn't specified in QEMU command line. It means we cannot treat -1 as
uninitialized state.
The patch defines -1 and -2 as VIRTIO_INVALID_EVENTFD and
VIRTIO_UNINITIALIZED_EVENTFD, and uses VIRTIO_UNINITIALIZED_EVENTFD for
the default values of kickfd and callfd.
Signed-off-by: Tetsuya Mukawa <mukawa@igel.co.jp>
---
lib/librte_vhost/rte_virtio_net.h | 2 ++
lib/librte_vhost/vhost_rxtx.c | 9 ++++++---
lib/librte_vhost/vhost_user/virtio-net-user.c | 14 +++++++-------
lib/librte_vhost/virtio-net.c | 4 ++--
4 files changed, 17 insertions(+), 12 deletions(-)
Comments
On Mon, Mar 14, 2016 at 05:53:32PM +0900, Tetsuya Mukawa wrote:
> Currently, default values of kickfd and callfd are -1.
> If the values are -1, current code guesses kickfd and callfd haven't
> been initialized yet. Then vhost library will guess the virtqueue isn't
> ready for processing.
> But callfd and kickfd will be set as -1 when "--enable-kvm"
> isn't specified in QEMU command line. It means we cannot treat -1 as
> uninitialized state.
> The patch defines -1 and -2 as VIRTIO_INVALID_EVENTFD and
> VIRTIO_UNINITIALIZED_EVENTFD, and uses VIRTIO_UNINITIALIZED_EVENTFD for
> the default values of kickfd and callfd.
Don't be mean to put an empty line between paragraphs :)
> Signed-off-by: Tetsuya Mukawa <mukawa@igel.co.jp>
Acked-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Thanks.
--yliu
2016-03-14 17:12, Yuanhan Liu:
> On Mon, Mar 14, 2016 at 05:53:32PM +0900, Tetsuya Mukawa wrote:
> > Currently, default values of kickfd and callfd are -1.
> > If the values are -1, current code guesses kickfd and callfd haven't
> > been initialized yet. Then vhost library will guess the virtqueue isn't
> > ready for processing.
> > But callfd and kickfd will be set as -1 when "--enable-kvm"
> > isn't specified in QEMU command line. It means we cannot treat -1 as
> > uninitialized state.
> > The patch defines -1 and -2 as VIRTIO_INVALID_EVENTFD and
> > VIRTIO_UNINITIALIZED_EVENTFD, and uses VIRTIO_UNINITIALIZED_EVENTFD for
> > the default values of kickfd and callfd.
>
> Don't be mean to put an empty line between paragraphs :)
>
> > Signed-off-by: Tetsuya Mukawa <mukawa@igel.co.jp>
>
> Acked-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Applied, thanks
@@ -89,6 +89,8 @@ struct vhost_virtqueue {
uint16_t vhost_hlen; /**< Vhost header length (varies depending on RX merge buffers. */
volatile uint16_t last_used_idx; /**< Last index used on the available ring */
volatile uint16_t last_used_idx_res; /**< Used for multiple devices reserving buffers. */
+#define VIRTIO_INVALID_EVENTFD (-1)
+#define VIRTIO_UNINITIALIZED_EVENTFD (-2)
int callfd; /**< Used to notify the guest (trigger interrupt). */
int kickfd; /**< Currently unused as polling mode is enabled. */
int enabled;
@@ -333,7 +333,8 @@ virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id,
rte_mb();
/* Kick the guest if necessary. */
- if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+ if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT)
+ && (vq->callfd >= 0))
eventfd_write(vq->callfd, (eventfd_t)1);
return count;
}
@@ -654,7 +655,8 @@ merge_rx_exit:
rte_mb();
/* Kick the guest if necessary. */
- if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+ if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT)
+ && (vq->callfd >= 0))
eventfd_write(vq->callfd, (eventfd_t)1);
}
@@ -1048,7 +1050,8 @@ rte_vhost_dequeue_burst(struct virtio_net *dev, uint16_t queue_id,
sizeof(vq->used->idx));
/* Kick guest if required. */
- if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
+ if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT)
+ && (vq->callfd >= 0))
eventfd_write(vq->callfd, (eventfd_t)1);
out:
@@ -225,8 +225,8 @@ static int
vq_is_ready(struct vhost_virtqueue *vq)
{
return vq && vq->desc &&
- vq->kickfd != -1 &&
- vq->callfd != -1;
+ vq->kickfd != VIRTIO_UNINITIALIZED_EVENTFD &&
+ vq->callfd != VIRTIO_UNINITIALIZED_EVENTFD;
}
static int
@@ -258,7 +258,7 @@ user_set_vring_call(struct vhost_device_ctx ctx, struct VhostUserMsg *pmsg)
file.index = pmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
if (pmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK)
- file.fd = -1;
+ file.fd = VIRTIO_INVALID_EVENTFD;
else
file.fd = pmsg->fds[0];
RTE_LOG(INFO, VHOST_CONFIG,
@@ -279,7 +279,7 @@ user_set_vring_kick(struct vhost_device_ctx ctx, struct VhostUserMsg *pmsg)
file.index = pmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
if (pmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK)
- file.fd = -1;
+ file.fd = VIRTIO_INVALID_EVENTFD;
else
file.fd = pmsg->fds[0];
RTE_LOG(INFO, VHOST_CONFIG,
@@ -316,10 +316,10 @@ user_get_vring_base(struct vhost_device_ctx ctx,
* sent and only sent in vhost_vring_stop.
* TODO: cleanup the vring, it isn't usable since here.
*/
- if (dev->virtqueue[state->index]->kickfd >= 0) {
+ if (dev->virtqueue[state->index]->kickfd >= 0)
close(dev->virtqueue[state->index]->kickfd);
- dev->virtqueue[state->index]->kickfd = -1;
- }
+
+ dev->virtqueue[state->index]->kickfd = VIRTIO_UNINITIALIZED_EVENTFD;
return 0;
}
@@ -167,8 +167,8 @@ init_vring_queue(struct vhost_virtqueue *vq, int qp_idx)
{
memset(vq, 0, sizeof(struct vhost_virtqueue));
- vq->kickfd = -1;
- vq->callfd = -1;
+ vq->kickfd = VIRTIO_UNINITIALIZED_EVENTFD;
+ vq->callfd = VIRTIO_UNINITIALIZED_EVENTFD;
/* Backends are set to -1 indicating an inactive device. */
vq->backend = -1;