On Sat, Mar 20, 2021 at 2:27 AM <pbhagavat...@marvell.com> wrote:
>
> From: Pavan Nikhilesh <pbhagavat...@marvell.com>
>
> Introduce rte_event_vector datastructure which is capable of holding
> multiple uintptr_t of the same flow thereby allowing applications
> to vectorize their pipeline and reducing the complexity of pipelining
> the events across multiple stages.
> This approach also reduces the scheduling overhead on a event device.
>
> Add a event vector mempool create handler to create mempools based on
> the best mempool ops available on a given platform.
>
> Signed-off-by: Pavan Nikhilesh <pbhagavat...@marvell.com>
Some minor comments below.
Feel free to add Acked-by: Jerin Jacob <jer...@marvell.com> after
fixing the comments and Ray's suggestion.
> ---
> doc/guides/prog_guide/eventdev.rst | 36 +++++++++-
> lib/librte_eventdev/rte_eventdev.h | 112 ++++++++++++++++++++++++++++-
> lib/librte_eventdev/version.map | 3 +
> 3 files changed, 148 insertions(+), 3 deletions(-)
>
> diff --git a/doc/guides/prog_guide/eventdev.rst
> b/doc/guides/prog_guide/eventdev.rst
> index ccde086f6..fda9c3743 100644
> --- a/doc/guides/prog_guide/eventdev.rst
> +++ b/doc/guides/prog_guide/eventdev.rst
> @@ -63,13 +63,45 @@ the actual event being scheduled is. The payload is a
> union of the following:
> * ``uint64_t u64``
> * ``void *event_ptr``
> * ``struct rte_mbuf *mbuf``
> +* ``struct rte_event_vector *vec``
>
> -These three items in a union occupy the same 64 bits at the end of the
> rte_event
> +These four items in a union occupy the same 64 bits at the end of the
> rte_event
> structure. The application can utilize the 64 bits directly by accessing the
> -u64 variable, while the event_ptr and mbuf are provided as convenience
> +u64 variable, while the event_ptr, mbuf, vec are provided as a convenience
> variables. For example the mbuf pointer in the union can used to schedule a
> DPDK packet.
>
> +Event Vector
> +~~~~~~~~~~~~
> +
> +The rte_event_vector struct contains a vector of elements defined by the
> event
> +type specified in the ``rte_event``. The event_vector structure contains the
> +following data:
> +
> +* ``nb_elem`` - The number of elements held within the vector.
> +
> +Similar to ``rte_event`` the payload of event vector is also a union,
> allowing
> +flexibility in what the actual vector is.
> +
> +* ``struct rte_mbuf *mbufs[0]`` - An array of mbufs.
> +* ``void *ptrs[0]`` - An array of pointers.
> +* ``uint64_t *u64s[0]`` - An array of uint64_t elements.
> +
> +The size of the event vector is related to the total number of elements it is
> +configured to hold, this is achieved by making `rte_event_vector` a variable
> +length structure.
> +A helper function is provided to create a mempool that holds event vector,
> which
> +takes name of the pool, total number of required ``rte_event_vector``,
> +cache size, number of elements in each ``rte_event_vector`` and socket id.
> +
> +.. code-block:: c
> +
> + rte_event_vector_pool_create("vector_pool", nb_event_vectors,
> cache_sz,
> + nb_elements_per_vector, socket_id);
> +
> +The function ``rte_event_vector_pool_create`` creates mempool with the best
> +platform mempool ops.
> +
> Queues
> ~~~~~~
>
> diff --git a/lib/librte_eventdev/rte_eventdev.h
> b/lib/librte_eventdev/rte_eventdev.h
> index ce1fc2ce0..5586a3f15 100644
> --- a/lib/librte_eventdev/rte_eventdev.h
> +++ b/lib/librte_eventdev/rte_eventdev.h
> @@ -212,8 +212,10 @@ extern "C" {
>
> #include <rte_common.h>
> #include <rte_config.h>
> -#include <rte_memory.h>
> #include <rte_errno.h>
> +#include <rte_mbuf_pool_ops.h>
> +#include <rte_memory.h>
> +#include <rte_mempool.h>
>
> #include "rte_eventdev_trace_fp.h"
>
> @@ -913,6 +915,25 @@ rte_event_dev_stop_flush_callback_register(uint8_t
> dev_id,
> int
> rte_event_dev_close(uint8_t dev_id);
>
> +/**
> + * Event vector structure.
> + */
> +struct rte_event_vector {
> + uint64_t nb_elem : 16;
> + /**< Number of elements in this event vector. */
> + uint64_t rsvd : 48;
Please add comment here to look Doxygen output correctly.
> + uint64_t impl_opaque;
Please add comment here to look Doxygen output correctly.
> + union {
> + struct rte_mbuf *mbufs[0];
> + void *ptrs[0];
> + uint64_t *u64s[0];
> + } __rte_aligned(16);
> + /**< Start of the vector array union. Depending upon the event type
> the
> + * vector array can be an array of mbufs or pointers or opaque u64
> + * values.
> + */
> +};
> +
> /* Scheduler type definitions */
> #define RTE_SCHED_TYPE_ORDERED 0
> /**< Ordered scheduling
> @@ -986,6 +1007,21 @@ rte_event_dev_close(uint8_t dev_id);
> */
> #define RTE_EVENT_TYPE_ETH_RX_ADAPTER 0x4
> /**< The event generated from event eth Rx adapter */
> +#define RTE_EVENT_TYPE_VECTOR 0x8
> +/**< Indicates that event is a vector.
> + * All vector event types should be an logical OR of EVENT_TYPE_VECTOR.
an logical -> a logical?
> + * This simplifies the pipeline design as we can split processing the events
we -> one
> + * between vector events and normal event across event types.
> + * Example:
> + * if (ev.event_type & RTE_EVENT_TYPE_VECTOR) {
> + * // Classify and handle vector event.
> + * } else {
> + * // Classify and handle event.
> + * }
> + */
> +#define RTE_EVENT_TYPE_CPU_VECTOR (RTE_EVENT_TYPE_VECTOR |
> RTE_EVENT_TYPE_CPU)
> +/**< The event vector generated from cpu for pipelining. */
> +
> #define RTE_EVENT_TYPE_MAX 0x10
> /**< Maximum number of event types */
>
> @@ -1108,6 +1144,8 @@ struct rte_event {
> /**< Opaque event pointer */
> struct rte_mbuf *mbuf;
> /**< mbuf pointer if dequeued event is associated with mbuf */
> + struct rte_event_vector *vec;
> + /**< Event vector pointer. */
> };
> };
>
> @@ -2023,6 +2061,78 @@ rte_event_dev_xstats_reset(uint8_t dev_id,
> */
> int rte_event_dev_selftest(uint8_t dev_id);
>
> +/**
> + * Get the memory required per event vector based on the number of elements
> per
> + * vector.
> + * This should be used to create the mempool that holds the event vectors.
> + *
> + * @param name
> + * The name of the vector pool.
> + * @param n
> + * The number of elements in the mbuf pool.
> + * @param cache_size
> + * Size of the per-core object cache. See rte_mempool_create() for
> + * details.
> + * @param nb_elem
> + * The number of elements then a single event vector should be able to
> hold.
> + * @param socket_id
> + * The socket identifier where the memory should be allocated. The
> + * value can be *SOCKET_ID_ANY* if there is no NUMA constraint for the
> + * reserved zone
> + *
> + * @return
> + * The pointer to the newly allocated mempool, on success. NULL on error
> + * with rte_errno set appropriately. Possible rte_errno values include:
> + * - E_RTE_NO_CONFIG - function could not get pointer to rte_config
> structure
> + * - E_RTE_SECONDARY - function was called from a secondary process
> instance
> + * - EINVAL - cache size provided is too large, or priv_size is not
> aligned.
> + * - ENOSPC - the maximum number of memzones has already been allocated
> + * - EEXIST - a memzone with the same name already exists
> + * - ENOMEM - no appropriate memory area found in which to create memzone
> + */
> +__rte_experimental
> +static inline struct rte_mempool *
> +rte_event_vector_pool_create(const char *name, unsigned int n,
> + unsigned int cache_size, uint16_t nb_elem,
> + int socket_id)
> +{
> + const char *mp_ops_name;
> + struct rte_mempool *mp;
> + unsigned int elt_sz;
> + int ret;
> +
> + if (!nb_elem) {
> + RTE_LOG(ERR, EVENTDEV,
> + "Invalid number of elements=%d requested\n", nb_elem);
> + rte_errno = -EINVAL;
> + return NULL;
> + }
> +
> + elt_sz =
> + sizeof(struct rte_event_vector) + (nb_elem *
> sizeof(uintptr_t));
> + mp = rte_mempool_create_empty(name, n, elt_sz, cache_size, 0,
> socket_id,
> + 0);
> + if (mp == NULL)
> + return NULL;
> +
> + mp_ops_name = rte_mbuf_best_mempool_ops();
> + ret = rte_mempool_set_ops_byname(mp, mp_ops_name, NULL);
> + if (ret != 0) {
> + RTE_LOG(ERR, EVENTDEV, "error setting mempool handler\n");
> + goto err;
> + }
> +
> + ret = rte_mempool_populate_default(mp);
> + if (ret < 0)
> + goto err;
> +
> + return mp;
> +err:
> + rte_mempool_free(mp);
> + rte_errno = -ret;
> + return NULL;
> +}
> +
> #ifdef __cplusplus
> }
> #endif
> diff --git a/lib/librte_eventdev/version.map b/lib/librte_eventdev/version.map
> index 3e5c09cfd..a070ef56e 100644
> --- a/lib/librte_eventdev/version.map
> +++ b/lib/librte_eventdev/version.map
> @@ -138,6 +138,9 @@ EXPERIMENTAL {
> __rte_eventdev_trace_port_setup;
> # added in 20.11
> rte_event_pmd_pci_probe_named;
> +
> + #added in 21.05
> + rte_event_vector_pool_create;
> };
>
> INTERNAL {
> --
> 2.17.1
>
