On 5/28/21 10:11 AM, Jiayu Hu wrote:
> This patch is to add thread unsafe version for async register and
> unregister functions.
>
> Signed-off-by: Jiayu Hu <jiayu...@intel.com>
> ---
> doc/guides/prog_guide/vhost_lib.rst | 12 +++
> lib/vhost/rte_vhost_async.h | 42 ++++++++++
> lib/vhost/version.map | 4 +
> lib/vhost/vhost.c | 161
> +++++++++++++++++++++++++++---------
> 4 files changed, 178 insertions(+), 41 deletions(-)
>
> diff --git a/doc/guides/prog_guide/vhost_lib.rst
> b/doc/guides/prog_guide/vhost_lib.rst
> index d18fb98..6b2745f 100644
> --- a/doc/guides/prog_guide/vhost_lib.rst
> +++ b/doc/guides/prog_guide/vhost_lib.rst
> @@ -253,6 +253,12 @@ The following is an overview of some key Vhost API
> functions:
> vhost invokes this function to get the copy data completed by async
> devices.
>
> +* ``rte_vhost_async_channel_register_thread_unsafe(vid, queue_id, features,
> ops)``
> + Register a vhost queue with async copy device channel without
> + performing any locking.
> +
> + This function is only safe to call from within vhost callback functions.
> +
> * ``rte_vhost_async_channel_unregister(vid, queue_id)``
>
> Unregister the async copy device channel from a vhost queue.
> @@ -265,6 +271,12 @@ The following is an overview of some key Vhost API
> functions:
> devices for all vhost queues in destroy_device(), when a
> virtio device is paused or shut down.
>
> +* ``rte_vhost_async_channel_unregister_thread_unsafe(vid, queue_id)``
> + Unregister the async copy device channel from a vhost queue without
> + performing any locking.
> +
> + This function is only safe to call from within vhost callback functions.
> +
> * ``rte_vhost_submit_enqueue_burst(vid, queue_id, pkts, count, comp_pkts,
> comp_count)``
>
> Submit an enqueue request to transmit ``count`` packets from host to guest
> diff --git a/lib/vhost/rte_vhost_async.h b/lib/vhost/rte_vhost_async.h
> index 6faa31f..d054b5f 100644
> --- a/lib/vhost/rte_vhost_async.h
> +++ b/lib/vhost/rte_vhost_async.h
> @@ -143,6 +143,48 @@ __rte_experimental
> int rte_vhost_async_channel_unregister(int vid, uint16_t queue_id);
>
> /**
> + * register an async channel for vhost without performing any locking
> + *
> + * @note This function does not perform any locking, and is only safe to call
> + * from within vhost callback functions.
> + *
> + * @param vid
> + * vhost device id async channel to be attached to
> + * @param queue_id
> + * vhost queue id async channel to be attached to
> + * @param features
> + * DMA channel feature bit
> + * b0 : DMA supports inorder data transfer
> + * b1 - b15: reserved
> + * b16 - b27: Packet length threshold for DMA transfer
> + * b28 - b31: reserved
> + * @param ops
> + * DMA operation callbacks
> + * @return
> + * 0 on success, -1 on failures
> + */
> +__rte_experimental
> +int rte_vhost_async_channel_register_thread_unsafe(int vid, uint16_t
> queue_id,
> + uint32_t features, struct rte_vhost_async_channel_ops *ops);
> +
> +/**
> + * unregister a dma channel for vhost without performing any lock
> + *
> + * @note This function does not perform any locking, and is only safe to call
> + * from within vhost callback functions.
> + *
> + * @param vid
> + * vhost device id DMA channel to be detached
> + * @param queue_id
> + * vhost queue id DMA channel to be detached
> + * @return
> + * 0 on success, -1 on failures
> + */
> +__rte_experimental
> +int rte_vhost_async_channel_unregister_thread_unsafe(int vid,
> + uint16_t queue_id);
> +
> +/**
> * This function submits enqueue data to async engine. Successfully
> * enqueued packets can be transfer completed or being occupied by DMA
> * engines, when this API returns. Transfer completed packets are returned
> diff --git a/lib/vhost/version.map b/lib/vhost/version.map
> index 9103a23..2363db8 100644
> --- a/lib/vhost/version.map
> +++ b/lib/vhost/version.map
> @@ -79,4 +79,8 @@ EXPERIMENTAL {
>
> # added in 21.05
> rte_vhost_get_negotiated_protocol_features;
> +
> + # added in 21.08
> + rte_vhost_async_channel_register_thread_unsafe;
> + rte_vhost_async_channel_unregister_thread_unsafe;
> };
> diff --git a/lib/vhost/vhost.c b/lib/vhost/vhost.c
> index c96f633..025e150 100644
> --- a/lib/vhost/vhost.c
> +++ b/lib/vhost/vhost.c
> @@ -1609,46 +1609,20 @@ int rte_vhost_extern_callback_register(int vid,
> return 0;
> }
>
> -int rte_vhost_async_channel_register(int vid, uint16_t queue_id,
> - uint32_t features,
> - struct rte_vhost_async_channel_ops *ops)
> +static __rte_always_inline int
> +async_channel_register(int vid, uint16_t queue_id,
> + struct rte_vhost_async_features f,
> + struct rte_vhost_async_channel_ops *ops)
> {
> - struct vhost_virtqueue *vq;
> struct virtio_net *dev = get_device(vid);
> - struct rte_vhost_async_features f;
> + struct vhost_virtqueue *vq = dev->virtqueue[queue_id];
> int node;
>
> - if (dev == NULL || ops == NULL)
> - return -1;
> -
> - f.intval = features;
> -
> - if (queue_id >= VHOST_MAX_VRING)
> - return -1;
> -
> - vq = dev->virtqueue[queue_id];
> -
> - if (unlikely(vq == NULL || !dev->async_copy))
> - return -1;
> -
> - if (unlikely(!f.async_inorder)) {
> - VHOST_LOG_CONFIG(ERR,
> - "async copy is not supported on non-inorder mode "
> - "(vid %d, qid: %d)\n", vid, queue_id);
> - return -1;
> - }
> -
> - if (unlikely(ops->check_completed_copies == NULL ||
> - ops->transfer_data == NULL))
> - return -1;
> -
> - rte_spinlock_lock(&vq->access_lock);
> -
> if (unlikely(vq->async_registered)) {
> VHOST_LOG_CONFIG(ERR,
> "async register failed: channel already registered "
> "(vid %d, qid: %d)\n", vid, queue_id);
> - goto reg_out;
> + return -1;
> }
>
> #ifdef RTE_LIBRTE_VHOST_NUMA
> @@ -1670,7 +1644,7 @@ int rte_vhost_async_channel_register(int vid, uint16_t
> queue_id,
> VHOST_LOG_CONFIG(ERR,
> "async register failed: cannot allocate memory for
> async_pkts_info "
> "(vid %d, qid: %d)\n", vid, queue_id);
> - goto reg_out;
> + return -1;
> }
>
> vq->it_pool = rte_malloc_socket(NULL,
> @@ -1681,7 +1655,7 @@ int rte_vhost_async_channel_register(int vid, uint16_t
> queue_id,
> VHOST_LOG_CONFIG(ERR,
> "async register failed: cannot allocate memory for
> it_pool "
> "(vid %d, qid: %d)\n", vid, queue_id);
> - goto reg_out;
> + return -1;
> }
>
> vq->vec_pool = rte_malloc_socket(NULL,
> @@ -1692,7 +1666,7 @@ int rte_vhost_async_channel_register(int vid, uint16_t
> queue_id,
> VHOST_LOG_CONFIG(ERR,
> "async register failed: cannot allocate memory for
> vec_pool "
> "(vid %d, qid: %d)\n", vid, queue_id);
> - goto reg_out;
> + return -1;
> }
>
> if (vq_is_packed(dev)) {
> @@ -1704,7 +1678,7 @@ int rte_vhost_async_channel_register(int vid, uint16_t
> queue_id,
> VHOST_LOG_CONFIG(ERR,
> "async register failed: cannot allocate memory
> for async buffers "
> "(vid %d, qid: %d)\n", vid, queue_id);
> - goto reg_out;
> + return -1;
> }
> } else {
> vq->async_descs_split = rte_malloc_socket(NULL,
> @@ -1715,22 +1689,92 @@ int rte_vhost_async_channel_register(int vid,
> uint16_t queue_id,
> VHOST_LOG_CONFIG(ERR,
> "async register failed: cannot allocate memory
> for async descs "
> "(vid %d, qid: %d)\n", vid, queue_id);
> - goto reg_out;
> + return -1;
> }
> }
>
> vq->async_ops.check_completed_copies = ops->check_completed_copies;
> vq->async_ops.transfer_data = ops->transfer_data;
> -
> vq->async_inorder = f.async_inorder;
> vq->async_threshold = f.async_threshold;
> -
> vq->async_registered = true;
>
> -reg_out:
> + return 0;
> +}
> +
> +int rte_vhost_async_channel_register(int vid, uint16_t queue_id,
> + uint32_t features,
> + struct rte_vhost_async_channel_ops *ops)
> +{
> + struct vhost_virtqueue *vq;
> + struct virtio_net *dev = get_device(vid);
> + struct rte_vhost_async_features f;
> + int ret;
> +
> + if (dev == NULL || ops == NULL)
> + return -1;
> +
> + f.intval = features;
Not directly related to this patch set, but could you please rework
struct rte_vhost_async_features? There is no point to pack the flags and
threshold values.
Also, the prototype should just pass the struct directly, or add
different fields for the threshold and the features.
> +
> + if (queue_id >= VHOST_MAX_VRING)
> + return -1;
> +
> + vq = dev->virtqueue[queue_id];
> +
> + if (unlikely(vq == NULL || !dev->async_copy))
> + return -1;
> +
> + if (unlikely(!f.async_inorder)) {
> + VHOST_LOG_CONFIG(ERR,
> + "async copy is not supported on non-inorder mode "
> + "(vid %d, qid: %d)\n", vid, queue_id);
> + return -1;
> + }
> +
> + if (unlikely(ops->check_completed_copies == NULL ||
> + ops->transfer_data == NULL))
> + return -1;
> +
> + rte_spinlock_lock(&vq->access_lock);
> + ret = async_channel_register(vid, queue_id, f, ops);
> rte_spinlock_unlock(&vq->access_lock);
>
> - return 0;
> + return ret;
> +}
> +
> +int rte_vhost_async_channel_register_thread_unsafe(int vid, uint16_t
> queue_id,
> + uint32_t features,
> + struct rte_vhost_async_channel_ops *ops)
> +{
> + struct vhost_virtqueue *vq;
> + struct virtio_net *dev = get_device(vid);
> + struct rte_vhost_async_features f;
> +
> + if (dev == NULL || ops == NULL)
> + return -1;
> +
> + f.intval = features;
> +
> + if (queue_id >= VHOST_MAX_VRING)
> + return -1;
> +
> + vq = dev->virtqueue[queue_id];
> +
> + if (unlikely(vq == NULL || !dev->async_copy))
> + return -1;
> +
> + if (unlikely(!f.async_inorder)) {
> + VHOST_LOG_CONFIG(ERR,
> + "async copy is not supported on non-inorder mode "
> + "(vid %d, qid: %d)\n", vid, queue_id);
> + return -1;
> + }
> +
> + if (unlikely(ops->check_completed_copies == NULL ||
> + ops->transfer_data == NULL))
> + return -1;
> +
> + return async_channel_register(vid, queue_id, f, ops);
> }
>
> int rte_vhost_async_channel_unregister(int vid, uint16_t queue_id)
> @@ -1780,5 +1824,40 @@ int rte_vhost_async_channel_unregister(int vid,
> uint16_t queue_id)
> return ret;
> }
>
> +int rte_vhost_async_channel_unregister_thread_unsafe(int vid,
> + uint16_t queue_id)
> +{
> + struct vhost_virtqueue *vq;
> + struct virtio_net *dev = get_device(vid);
> +
> + if (dev == NULL)
> + return -1;
> +
> + if (queue_id >= VHOST_MAX_VRING)
> + return -1;
> +
> + vq = dev->virtqueue[queue_id];
> +
> + if (vq == NULL)
> + return -1;
> +
> + if (!vq->async_registered)
> + return 0;
> +
> + if (vq->async_pkts_inflight_n) {
> + VHOST_LOG_CONFIG(ERR, "Failed to unregister async channel. "
> + "async inflight packets must be completed before
> unregistration.\n");
> + return -1;
> + }
> +
> + vhost_free_async_mem(vq);
> +
> + vq->async_ops.transfer_data = NULL;
> + vq->async_ops.check_completed_copies = NULL;
> + vq->async_registered = false;
> +
> + return 0;
> +}
> +
> RTE_LOG_REGISTER_SUFFIX(vhost_config_log_level, config, INFO);
> RTE_LOG_REGISTER_SUFFIX(vhost_data_log_level, data, WARNING);
>
