> -----Original Message-----
> From: Wu, Jingjing
> Sent: Thursday, August 24, 2017 10:11 AM
> To: Tan, Jianfeng
> Cc: Wu, Jingjing; dev@dpdk.org
> Subject: [PATCH v3] eal: add counter size for efd clean
>
> For virtual device, the rte_intr_handle struct is
> initialized by the virtual device driver, including
> the event fd assignment. If the event fd need to be
> read for clean, an argument is required for the proper
> event fd read.
>
> This patch adds efd_counter_size in rte_intr_handle
> struct to tell the rx interrupt process the read size.
>
> Signed-off-by: Jingjing Wu <jingjing...@intel.com>
Reviewed-by: Jianfeng Tan <jianfeng....@intel.com>
Thanks,
Jianfeng
> ---
>
> v3 change:
> - rework commit log
>
> v2 change:
> - fix typo and reword commit log
>
> drivers/net/virtio/virtio_user/virtio_user_dev.c | 2 ++
> lib/librte_eal/linuxapp/eal/eal_interrupts.c | 19
> ++++++++++++-------
> .../linuxapp/eal/include/exec-env/rte_interrupts.h | 1 +
> 3 files changed, 15 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.c
> b/drivers/net/virtio/virtio_user/virtio_user_dev.c
> index 7941271..906d7a2 100644
> --- a/drivers/net/virtio/virtio_user/virtio_user_dev.c
> +++ b/drivers/net/virtio/virtio_user/virtio_user_dev.c
> @@ -270,6 +270,8 @@ virtio_user_fill_intr_handle(struct virtio_user_dev
> *dev)
> eth_dev->intr_handle->nb_efd = dev->max_queue_pairs;
> eth_dev->intr_handle->max_intr = dev->max_queue_pairs + 1;
> eth_dev->intr_handle->type = RTE_INTR_HANDLE_VDEV;
> + /* For virtio vdev, no need to read counter for clean */
> + eth_dev->intr_handle->efd_counter_size = 0;
> if (dev->vhostfd >= 0)
> eth_dev->intr_handle->fd = dev->vhostfd;
>
> diff --git a/lib/librte_eal/linuxapp/eal/eal_interrupts.c
> b/lib/librte_eal/linuxapp/eal/eal_interrupts.c
> index 3e9ac41..7de39c3 100644
> --- a/lib/librte_eal/linuxapp/eal/eal_interrupts.c
> +++ b/lib/librte_eal/linuxapp/eal/eal_interrupts.c
> @@ -914,7 +914,7 @@ static void
> eal_intr_proc_rxtx_intr(int fd, const struct rte_intr_handle *intr_handle)
> {
> union rte_intr_read_buffer buf;
> - int bytes_read = 1;
> + int bytes_read = 0;
> int nbytes;
>
> switch (intr_handle->type) {
> @@ -930,11 +930,9 @@ eal_intr_proc_rxtx_intr(int fd, const struct
> rte_intr_handle *intr_handle)
> break;
> #endif
> case RTE_INTR_HANDLE_VDEV:
> - /* for vdev, fd points to:
> - * a. eventfd which does not need to read out;
> - * b. datapath fd which needs PMD to read out.
> - */
> - return;
> + bytes_read = intr_handle->efd_counter_size;
> + /* For vdev, number of bytes to read is set by driver */
> + break;
> case RTE_INTR_HANDLE_EXT:
> return;
> default:
> @@ -947,6 +945,8 @@ eal_intr_proc_rxtx_intr(int fd, const struct
> rte_intr_handle *intr_handle)
> * read out to clear the ready-to-be-read flag
> * for epoll_wait.
> */
> + if (bytes_read == 0)
> + return;
> do {
> nbytes = read(fd, &buf, bytes_read);
> if (nbytes < 0) {
> @@ -1206,7 +1206,12 @@ rte_intr_efd_enable(struct rte_intr_handle
> *intr_handle, uint32_t nb_efd)
> intr_handle->nb_efd = n;
> intr_handle->max_intr = NB_OTHER_INTR + n;
> } else if (intr_handle->type == RTE_INTR_HANDLE_VDEV) {
> - /* do nothing, and let vdev driver to initialize this struct */
> + /* only check, initialization would be done in vdev driver.*/
> + if (intr_handle->efd_counter_size >
> + sizeof(union rte_intr_read_buffer)) {
> + RTE_LOG(ERR, EAL, "the efd_counter_size is
> oversized");
> + return -EINVAL;
> + }
> } else {
> intr_handle->efds[0] = intr_handle->fd;
> intr_handle->nb_efd = RTE_MIN(nb_efd, 1U);
> diff --git a/lib/librte_eal/linuxapp/eal/include/exec-env/rte_interrupts.h
> b/lib/librte_eal/linuxapp/eal/include/exec-env/rte_interrupts.h
> index 6daffeb..fd4ea6c 100644
> --- a/lib/librte_eal/linuxapp/eal/include/exec-env/rte_interrupts.h
> +++ b/lib/librte_eal/linuxapp/eal/include/exec-env/rte_interrupts.h
> @@ -93,6 +93,7 @@ struct rte_intr_handle {
> enum rte_intr_handle_type type; /**< handle type */
> uint32_t max_intr; /**< max interrupt requested */
> uint32_t nb_efd; /**< number of available efd(event fd) */
> + uint8_t efd_counter_size; /**< size of efd counter, used for vdev
> */
> int efds[RTE_MAX_RXTX_INTR_VEC_ID]; /**< intr vectors/efds
> mapping */
> struct rte_epoll_event elist[RTE_MAX_RXTX_INTR_VEC_ID];
> /**< intr vector epoll event */
> --
> 2.4.11
