RE: [RFC 0/2] introduce event vector adapter

[Pavan Nikhilesh Bhagavatula <pbhagavatula@marvell.com>]

++

> -----Original Message-----
> From: pbhagavatula@marvell.com <pbhagavatula@marvell.com>
> Sent: Wednesday, March 26, 2025 6:45 PM
> To: Jerin Jacob <jerinj@marvell.com>
> Cc: dev@dpdk.org; Pavan Nikhilesh Bhagavatula
> <pbhagavatula@marvell.com>
> Subject: [RFC 0/2] introduce event vector adapter
> 
> From: Pavan Nikhilesh <pbhagavatula@marvell.com>
> 
> The event vector adapter supports offloading the creation of event vectors
> by vectorizing objects (mbufs/ptrs/u64s).
> 
> An event vector adapter has the following working model:
> 
>          ┌──────────┐
>          │  Vector  ├─┐
>          │ adapter0 │ │
>          └──────────┘ │
>          ┌──────────┐ │   ┌──────────┐
>          │  Vector  ├─┼──►│  Event   │
>          │ adapter1 │ │   │  Queue0  │
>          └──────────┘ │   └──────────┘
>          ┌──────────┐ │
>          │  Vector  ├─┘
>          │ adapter2 │
>          └──────────┘
> 
>          ┌──────────┐
>          │  Vector  ├─┐
>          │ adapter0 │ │   ┌──────────┐
>          └──────────┘ ├──►│  Event   │
>          ┌──────────┐ │   │  Queue1  │
>          │  Vector  ├─┘   └──────────┘
>          │ adapter1 │
>          └──────────┘
> 
>  - A vector adapter can be seen as an extension to event queue. It helps in
>    aggregating objects and generating a vector event which is enqueued to the
>    event queue.
> 
>  - Multiple vector adapters can be created on an event queue, each with its
>    own unique properties such as event properties, vector size, and timeout.
>    Note: If the target event queue doesn't support
> RTE_EVENT_QUEUE_CFG_ALL_TYPES,
>          then the vector adapter should use the same schedule type as the event
>          queue.
> 
>  - Each vector adapter aggregates objects, generates a vector event and
>    enqueues it to the event queue with the event properties mentioned in
>    rte_event_vector_adapter_conf::ev.
> 
>  - After configuring the vector adapter, the Application needs to use the
>    rte_event_vector_adapter_enqueue() function to enqueue objects i.e.,
>    mbufs/ptrs/u64s to the vector adapter.
>    On reaching the configured vector size or timeout, the vector adapter
>    enqueues the event vector to the event queue.
>    Note: Application should use the event_type and sub_event_type properly
>          identifying the contents of vector event on dequeue.
> 
>  - If the vector adapter advertises the
> RTE_EVENT_VECTOR_ADAPTER_CAP_SOV_EOV
>   capability, application can use the RTE_EVENT_VECTOR_ENQ_[S|E]OV flags
>   to indicate the start and end of a vector event.
>   * When RTE_EVENT_VECTOR_ENQ_SOV is set, the vector adapter will flush
> any
>     aggregation in progress as a vector event and start aggregating a new
>     vector event with the enqueued ptr.
>   * When RTE_EVENT_VECTOR_ENQ_EOV is set, the vector adapter will add the
>     current ptr enqueued to the aggregated event and enqueue the vector event
>     to the event queue.
>   * If both flags are set, the vector adapter will flush the current aggregation
>     as a vector event and enqueue the current ptr as a single event to the event
>     queue.
> 
>  - If the vector adapter reaches the configured vector size, it will enqueue
>    the aggregated vector event to the event queue.
> 
>  - If the vector adapter reaches the configured vector timeout, it will flush
>    the current aggregation as a vector event if the minimum vector size is
>    reached, if not it will enqueue the objects as single events to the event
>    queue.
> 
>  - If the vector adapter is unable to aggregate the objects into a vector event,
>    it will enqueue the objects as single events to the event queue with the event
>    properties mentioned in rte_event_vector_adapter_conf::ev_fallback.
> 
>  Before using the vector adapter, the application has to create and configure
>  an event device and based on the event device capability it might require
>  creating an additional event port.
> 
>  When the application creates the vector adapter using the
>  ``rte_event_vector_adapter_create()`` function, the event device driver
>  capabilities are checked. If an in-built port is absent, the application
>  uses the default function to create a new event port.
>  For finer control over event port creation, the application should use
>  the ``rte_event_vector_adapter_create_ext()`` function.
> 
>  The application can enqueue one or more objects to the vector adapter using
> the
>  ``rte_event_vector_adapter_enqueue()`` function and control the aggregation
>  using the flags.
> 
>  Vector adapters report stats using the
> ``rte_event_vector_adapter_stats_get()``
>  function and reset the stats using the
> ``rte_event_vector_adapter_stats_reset()``.
> 
>  The application can destroy the vector adapter using the
>  ``rte_event_vector_adapter_destroy()`` function.
> 
> Pavan Nikhilesh (2):
>   eventdev: introduce event vector adapter
>   eventdev: add default software vector adapter
> 
>  config/rte_config.h                     |   1 +
>  lib/eventdev/event_vector_adapter_pmd.h |  87 +++
>  lib/eventdev/eventdev_pmd.h             |  38 ++
>  lib/eventdev/meson.build                |   3 +
>  lib/eventdev/rte_event_vector_adapter.c | 762
> ++++++++++++++++++++++++
>  lib/eventdev/rte_event_vector_adapter.h | 469 +++++++++++++++
>  lib/eventdev/rte_eventdev.c             |  23 +
>  lib/eventdev/rte_eventdev.h             |   8 +
>  lib/eventdev/version.map                |  13 +
>  9 files changed, 1404 insertions(+)
>  create mode 100644 lib/eventdev/event_vector_adapter_pmd.h
>  create mode 100644 lib/eventdev/rte_event_vector_adapter.c
>  create mode 100644 lib/eventdev/rte_event_vector_adapter.h
> 
> --
> 2.43.0