On 7/29/20 11:20 AM, Maxime Coquelin wrote:
> At .new_device() time, only the first vring pair is
> now ready, other vrings are consfigured later.
>
> Problem is that when application will setup and enable
> interrupts, only the first queue pair Rx interrupt will
> be enabled.
>
> This patches fixes the issue by setting the number of
> max interrupts to the number of Rx queues that will be
> later initialized. Then, as soon as a Rx vring is ready
> and interrupt enabled by the application, it removes the
> corresponding uninitialized epoll event, and install a
> new one with the valid FD.
>
> Fixes: 604052ae5395 ("net/vhost: support queue update")
>
> Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
> ---
> drivers/net/vhost/rte_eth_vhost.c | 75 +++++++++++++++++++++++++++----
> 1 file changed, 66 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/net/vhost/rte_eth_vhost.c
> b/drivers/net/vhost/rte_eth_vhost.c
> index 951929c663..237785dd66 100644
> --- a/drivers/net/vhost/rte_eth_vhost.c
> +++ b/drivers/net/vhost/rte_eth_vhost.c
> @@ -5,6 +5,7 @@
> #include <unistd.h>
> #include <pthread.h>
> #include <stdbool.h>
> +#include <sys/epoll.h>
>
> #include <rte_mbuf.h>
> #include <rte_ethdev_driver.h>
> @@ -95,6 +96,8 @@ struct vhost_queue {
> uint16_t port;
> uint16_t virtqueue_id;
> struct vhost_stats stats;
> + int intr_enable;
> + rte_spinlock_t intr_lock;
> };
>
> struct pmd_internal {
> @@ -524,6 +527,45 @@ find_internal_resource(char *ifname)
> return list;
> }
>
> +static int
> +eth_vhost_update_intr(struct rte_eth_dev *eth_dev, uint16_t rxq_idx)
> +{
> + struct rte_intr_handle *handle = eth_dev->intr_handle;
> + struct rte_epoll_event rev;
> + int epfd, ret;
> +
Chenbo reported that we can have a NULL pointer dereference on handle
when using Virtio-user on the other end and quitting.
> + if (handle->efds[rxq_idx] == handle->elist[rxq_idx].fd)
> + return 0;
> +
> + VHOST_LOG(INFO, "kickfd for rxq-%d was changed, updating handler.\n",
> + rxq_idx);
> +
> + /*
> + * First remove invalid epoll event, and then isntall
> + * the new one. May be solved with a proper API in the
> + * future.
> + */
> + epfd = handle->elist[rxq_idx].epfd;
> + rev = handle->elist[rxq_idx];
> + ret = rte_epoll_ctl(epfd, EPOLL_CTL_DEL, rev.fd,
> + &handle->elist[rxq_idx]);
> + if (ret) {
> + VHOST_LOG(ERR, "Delete epoll event failed.\n");
> + return ret;
> + }
> +
> + rev.fd = handle->efds[rxq_idx];
> + handle->elist[rxq_idx] = rev;
> + ret = rte_epoll_ctl(epfd, EPOLL_CTL_ADD, rev.fd,
> + &handle->elist[rxq_idx]);
> + if (ret) {
> + VHOST_LOG(ERR, "Add epoll event failed.\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> static int
> eth_rxq_intr_enable(struct rte_eth_dev *dev, uint16_t qid)
> {
> @@ -537,6 +579,11 @@ eth_rxq_intr_enable(struct rte_eth_dev *dev, uint16_t
> qid)
> return -1;
> }
>
> + rte_spinlock_lock(&vq->intr_lock);
> + vq->intr_enable = 1;
> + ret = eth_vhost_update_intr(dev, qid);
> + rte_spinlock_unlock(&vq->intr_lock);
> +
I missed to check ret value here, will add it in v4.
> ret = rte_vhost_get_vhost_vring(vq->vid, (qid << 1) + 1, &vring);
> if (ret < 0) {
> VHOST_LOG(ERR, "Failed to get rxq%d's vring\n", qid);
