> -----Original Message-----
> From: Maxime Coquelin <maxime.coque...@redhat.com>
> Sent: Friday, March 31, 2023 11:43 PM
> To: dev@dpdk.org; david.march...@redhat.com; Xia, Chenbo
> <chenbo....@intel.com>; m...@redhat.com; f...@redhat.com;
> jasow...@redhat.com; Liang, Cunming <cunming.li...@intel.com>; Xie, Yongji
> <xieyon...@bytedance.com>; echau...@redhat.com; epere...@redhat.com;
> amore...@redhat.com
> Cc: Maxime Coquelin <maxime.coque...@redhat.com>
> Subject: [RFC 22/27] vhost: add VDUSE events handler
>
> This patch makes use of Vhost lib's FD manager to install
> a handler for VDUSE events occurring on the VDUSE device FD.
>
> Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
> ---
> lib/vhost/vduse.c | 102 ++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 102 insertions(+)
>
> diff --git a/lib/vhost/vduse.c b/lib/vhost/vduse.c
> index afa8a39498..2a183130d3 100644
> --- a/lib/vhost/vduse.c
> +++ b/lib/vhost/vduse.c
> @@ -17,6 +17,7 @@
>
> #include <rte_common.h>
>
> +#include "fd_man.h"
> #include "iotlb.h"
> #include "vduse.h"
> #include "vhost.h"
> @@ -32,6 +33,27 @@
> (1ULL << VIRTIO_F_IN_ORDER) | \
> (1ULL << VIRTIO_F_IOMMU_PLATFORM))
>
> +struct vduse {
> + struct fdset fdset;
> +};
> +
> +static struct vduse vduse = {
> + .fdset = {
> + .fd = { [0 ... MAX_FDS - 1] = {-1, NULL, NULL, NULL, 0} },
> + .fd_mutex = PTHREAD_MUTEX_INITIALIZER,
> + .fd_pooling_mutex = PTHREAD_MUTEX_INITIALIZER,
> + .num = 0
> + },
> +};
> +
> +static bool vduse_events_thread;
> +
> +static const char * const vduse_reqs_str[] = {
> + "VDUSE_GET_VQ_STATE",
> + "VDUSE_SET_STATUS",
> + "VDUSE_UPDATE_IOTLB",
> +};
> +
> static int
> vduse_inject_irq(struct virtio_net *dev, struct vhost_virtqueue *vq)
> {
> @@ -105,16 +127,84 @@ static struct vhost_backend_ops vduse_backend_ops =
> {
> .inject_irq = vduse_inject_irq,
> };
>
> +static void
> +vduse_events_handler(int fd, void *arg, int *remove __rte_unused)
> +{
> + struct virtio_net *dev = arg;
> + struct vduse_dev_request req;
> + struct vduse_dev_response resp;
> + int ret;
> +
> + memset(&resp, 0, sizeof(resp));
> +
> + ret = read(fd, &req, sizeof(req));
> + if (ret < 0) {
> + VHOST_LOG_CONFIG(dev->ifname, ERR, "Failed to read
> request: %s\n",
> + strerror(errno));
> + return;
> + } else if (ret < (int)sizeof(req)) {
> + VHOST_LOG_CONFIG(dev->ifname, ERR, "Incomplete to read
> request %d\n", ret);
> + return;
> + }
> +
> + pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
> +
> + VHOST_LOG_CONFIG(dev->ifname, INFO, "New request: %s (%u)\n",
> + req.type < RTE_DIM(vduse_reqs_str) ?
> + vduse_reqs_str[req.type] : "Unknown",
> + req.type);
> +
> + switch (req.type) {
> + default:
> + resp.result = VDUSE_REQ_RESULT_FAILED;
> + break;
> + }
> +
> + pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
> +
> + resp.request_id = req.request_id;
> +
> + ret = write(dev->vduse_dev_fd, &resp, sizeof(resp));
> + if (ret != sizeof(resp)) {
> + VHOST_LOG_CONFIG(dev->ifname, ERR, "Failed to write
> response %s\n",
> + strerror(errno));
> + return;
> + }
> +}
> +
> int
> vduse_device_create(const char *path)
> {
> int control_fd, dev_fd, vid, ret;
> + pthread_t fdset_tid;
> uint32_t i;
> struct virtio_net *dev;
> uint64_t ver = VHOST_VDUSE_API_VERSION;
> struct vduse_dev_config *dev_config = NULL;
> const char *name = path + strlen("/dev/vduse/");
>
> + /* If first device, create events dispatcher thread */
> + if (vduse_events_thread == false) {
> + /**
> + * create a pipe which will be waited by poll and notified to
> + * rebuild the wait list of poll.
> + */
> + if (fdset_pipe_init(&vduse.fdset) < 0) {
> + VHOST_LOG_CONFIG(path, ERR, "failed to create pipe for
> vduse fdset\n");
> + return -1;
> + }
> +
> + ret = rte_ctrl_thread_create(&fdset_tid, "vduse-events", NULL,
> + fdset_event_dispatch, &vduse.fdset);
> + if (ret != 0) {
> + VHOST_LOG_CONFIG(path, ERR, "failed to create vduse
> fdset handling thread\n");
> + fdset_pipe_uninit(&vduse.fdset);
> + return -1;
> + }
> +
> + vduse_events_thread = true;
> + }
> +
> control_fd = open(VDUSE_CTRL_PATH, O_RDWR);
> if (control_fd < 0) {
> VHOST_LOG_CONFIG(name, ERR, "Failed to open %s: %s\n",
> @@ -198,6 +288,13 @@ vduse_device_create(const char *path)
> }
> }
>
> + ret = fdset_add(&vduse.fdset, dev->vduse_dev_fd,
> vduse_events_handler, NULL, dev);
> + if (ret) {
> + VHOST_LOG_CONFIG(name, ERR, "Failed to add fd %d to vduse
> fdset\n",
> + dev->vduse_dev_fd);
> + goto out_dev_destroy;
> + }
> +
> free(dev_config);
>
> return 0;
> @@ -236,11 +333,16 @@ vduse_device_destroy(const char *path)
> if (vid == RTE_MAX_VHOST_DEVICE)
> return -1;
>
> + fdset_del(&vduse.fdset, dev->vduse_dev_fd);
> +
> if (dev->vduse_dev_fd >= 0) {
> close(dev->vduse_dev_fd);
> dev->vduse_dev_fd = -1;
> }
>
> + sleep(2); //ToDo: Need to rework fdman to ensure the deleted FD is
> no
> + //more being polled, otherwise VDUSE_DESTROY_DEV will fail.
> +
> if (dev->vduse_ctrl_fd >= 0) {
> ret = ioctl(dev->vduse_ctrl_fd, VDUSE_DESTROY_DEV, name);
> if (ret)
> --
> 2.39.2
Reviewed-by: Chenbo Xia <chenbo....@intel.com>
