On Wed, Oct 2, 2024 at 2:19 AM <pbhagavat...@marvell.com> wrote:
>
> From: Pavan Nikhilesh <pbhagavat...@marvell.com>
>
> Add a new eventdev API to provide a hint to the eventdev PMD to
> pre-schedule the next event into the event port, without releasing
> the current flow context.
> Event device that support this feature advertises the capability
> using the RTE_EVENT_DEV_CAP_SW_PRESCHEDULE capability flag.
Change to RTE_EVENT_DEV_CAP_PRESCHEDULE_* prefix like other capas.
>
> Application can invoke `rte_event_port_preschedule` to hint the PMD.
>
> Signed-off-by: Pavan Nikhilesh <pbhagavat...@marvell.com>
> ---
> doc/guides/prog_guide/eventdev/eventdev.rst | 8 ++++
> doc/guides/rel_notes/release_24_11.rst | 3 +-
> lib/eventdev/eventdev_pmd.h | 2 +
> lib/eventdev/eventdev_private.c | 21 ++++++++-
> lib/eventdev/eventdev_trace_points.c | 3 ++
> lib/eventdev/rte_eventdev.h | 49 +++++++++++++++++++++
> lib/eventdev/rte_eventdev_core.h | 5 +++
> lib/eventdev/rte_eventdev_trace_fp.h | 8 ++++
> lib/eventdev/version.map | 2 +
> 9 files changed, 98 insertions(+), 3 deletions(-)
>
> diff --git a/doc/guides/prog_guide/eventdev/eventdev.rst
> b/doc/guides/prog_guide/eventdev/eventdev.rst
> index 2deab0333e..1d8b86ab66 100644
> --- a/doc/guides/prog_guide/eventdev/eventdev.rst
> +++ b/doc/guides/prog_guide/eventdev/eventdev.rst
> @@ -390,6 +390,14 @@ To enable or disable event pre-scheduling at a given
> event port, the application
> // Disable pre-scheduling if thread is about to be scheduled out and
> issue dequeue() to drain
> // pending events.
>
> +Event Pre-schedule Hint can be used to provide a hint to the eventdev PMD to
> pre-schedule the next
pre-schedule
Hint -> hint
Application may provide pre-schedule hint to eventdev PMD to pre-schedule ....
> +event without releasing the current flow context. Event device that support
> this feature advertises
> +the capability using the ``RTE_EVENT_DEV_CAP_SW_PRESCHEDULE`` capability
> flag.
SW is a very overloaded term, How about RTE_EVENT_DEV_CAP_PRESCHEDULE_EXPLICT?
Tell it is HINT. No need to check the capability in fast path.
> +If pre-scheduling is already enabled at a event device or event port level
> then the hint is ignored.
> +
> +.. code-block:: c
> +
> + rte_event_port_preschedule(dev_id, port_id, RTE_EVENT_DEV_PRESCHEDULE);
Since it is used at port level. Remove _DEV_.
>
> Starting the EventDev
> ~~~~~~~~~~~~~~~~~~~~~
> diff --git a/doc/guides/rel_notes/release_24_11.rst
> b/doc/guides/rel_notes/release_24_11.rst
> index 6e36ac7b7e..3ada21c084 100644
> --- a/doc/guides/rel_notes/release_24_11.rst
> +++ b/doc/guides/rel_notes/release_24_11.rst
> @@ -64,7 +64,8 @@ New Features
> level pre-scheduling type.
> * Added ``rte_event_port_preschedule_modify`` to modify pre-scheduling type
> on a given event port.
> -
> + * Added ``rte_event_port_preschedule`` to allow applications to decide when
> + to pre-schedule events on an event port.
As an explicit request or so.
>
> Removed Items
> -------------
> diff --git a/lib/eventdev/eventdev_pmd.h b/lib/eventdev/eventdev_pmd.h
> index 9ea23aa6cd..0bee2347ef 100644
> --- a/lib/eventdev/eventdev_pmd.h
> +++ b/lib/eventdev/eventdev_pmd.h
> @@ -186,6 +186,8 @@ struct __rte_cache_aligned rte_eventdev {
> /**< Pointer to PMD Event switch profile function. */
> event_preschedule_modify_t preschedule_modify;
> /**< Pointer to PMD Event port pre-schedule type modify function. */
> + event_preschedule_t preschedule;
> + /**< Pointer to PMD Event port pre-schedule function. */
>
> uint64_t reserved_64s[3]; /**< Reserved for future fields */
> void *reserved_ptrs[3]; /**< Reserved for future fields */
> diff --git a/lib/eventdev/eventdev_private.c b/lib/eventdev/eventdev_private.c
> index dc37f736f8..6aed1cba9a 100644
> --- a/lib/eventdev/eventdev_private.c
> +++ b/lib/eventdev/eventdev_private.c
> @@ -111,6 +111,19 @@ dummy_event_port_preschedule_modify_hint(__rte_unused
> void *port,
> return -ENOTSUP;
> }
>
> +static void
> +dummy_event_port_preschedule(__rte_unused void *port,
> + __rte_unused rte_event_dev_preschedule_type_t
> preschedule)
> +{
> + RTE_EDEV_LOG_ERR("pre-schedule requested for unconfigured event
> device");
> +}
> +
> +static void
> +dummy_event_port_preschedule_hint(__rte_unused void *port,
> + __rte_unused rte_event_dev_preschedule_type_t
> preschedule)
> +{
> +}
> +
> void
> event_dev_fp_ops_reset(struct rte_event_fp_ops *fp_op)
> {
> @@ -124,12 +137,12 @@ event_dev_fp_ops_reset(struct rte_event_fp_ops *fp_op)
> .dequeue_burst = dummy_event_dequeue_burst,
> .maintain = dummy_event_maintain,
> .txa_enqueue = dummy_event_tx_adapter_enqueue,
> - .txa_enqueue_same_dest =
> - dummy_event_tx_adapter_enqueue_same_dest,
> + .txa_enqueue_same_dest =
> dummy_event_tx_adapter_enqueue_same_dest,
> .ca_enqueue = dummy_event_crypto_adapter_enqueue,
> .dma_enqueue = dummy_event_dma_adapter_enqueue,
> .profile_switch = dummy_event_port_profile_switch,
> .preschedule_modify = dummy_event_port_preschedule_modify,
> + .preschedule = dummy_event_port_preschedule,
> .data = dummy_data,
> };
>
> @@ -153,8 +166,12 @@ event_dev_fp_ops_set(struct rte_event_fp_ops *fp_op,
> fp_op->dma_enqueue = dev->dma_enqueue;
> fp_op->profile_switch = dev->profile_switch;
> fp_op->preschedule_modify = dev->preschedule_modify;
> + fp_op->preschedule = dev->preschedule;
> fp_op->data = dev->data->ports;
>
> if (fp_op->preschedule_modify == NULL)
> fp_op->preschedule_modify =
> dummy_event_port_preschedule_modify_hint;
> +
> + if (fp_op->preschedule == NULL)
> + fp_op->preschedule = dummy_event_port_preschedule_hint;
> }
> diff --git a/lib/eventdev/eventdev_trace_points.c
> b/lib/eventdev/eventdev_trace_points.c
> index e41674123c..e7af1591f7 100644
> --- a/lib/eventdev/eventdev_trace_points.c
> +++ b/lib/eventdev/eventdev_trace_points.c
> @@ -52,6 +52,9 @@
> RTE_TRACE_POINT_REGISTER(rte_eventdev_trace_port_profile_switch,
> RTE_TRACE_POINT_REGISTER(rte_eventdev_trace_port_preschedule_modify,
> lib.eventdev.port.preschedule.modify)
>
> +RTE_TRACE_POINT_REGISTER(rte_eventdev_trace_port_preschedule,
> + lib.eventdev.port.preschedule)
> +
> /* Eventdev Rx adapter trace points */
> RTE_TRACE_POINT_REGISTER(rte_eventdev_trace_eth_rx_adapter_create,
> lib.eventdev.rx.adapter.create)
> diff --git a/lib/eventdev/rte_eventdev.h b/lib/eventdev/rte_eventdev.h
> index 0add0093ac..8df6a8bee1 100644
> --- a/lib/eventdev/rte_eventdev.h
> +++ b/lib/eventdev/rte_eventdev.h
> @@ -480,6 +480,15 @@ struct rte_event;
> * @see rte_event_port_preschedule_modify()
> */
>
> +#define RTE_EVENT_DEV_CAP_SW_PRESCHEDULE (1ULL << 19)
> +/**< Event device supports software prescheduling.
> + *
> + * When this flag is set, the application can issue preschedule request on
> + * a event port.
> + *
> + * @see rte_event_port_preschedule()
> + */
> +
> /* Event device priority levels */
> #define RTE_EVENT_DEV_PRIORITY_HIGHEST 0
> /**< Highest priority level for events and queues.
> @@ -2977,6 +2986,46 @@ rte_event_port_preschedule_modify(uint8_t dev_id,
> uint8_t port_id,
> return fp_ops->preschedule_modify(port, type);
> }
>
> +/**
> + * Provide a hint to the event device to pre-schedule events to event port .
> + *
> + * Hint the event device to pre-schedule events to the event port.
> + * The call doesn't not guarantee that the events will be pre-scheduleed.
> + * The call doesn't release the flow context currently held by the event
> port.
> + * The event device should support RTE_EVENT_DEV_CAP_SW_PRESCHEDULE
> capability.
Reword the comments.
> + *
> + * When pre-scheduling is enabled at an event device or event port level, the
> + * hint is ignored.
> + *
> + * Subsequent calls to rte_event_dequeue_burst() will dequeue the
> pre-schedule
> + * events but pre-schedule operation is not issued again.
> + *
> + * @param dev_id
> + * The identifier of the device.
> + * @param port_id
> + * The identifier of the event port.
> + * @param type
> + * The pre-schedule type to use on the event port.
> + */
> +static inline void
> +rte_event_port_preschedule(uint8_t dev_id, uint8_t port_id,
> rte_event_dev_preschedule_type_t type)
> +{
> + const struct rte_event_fp_ops *fp_ops;
> + void *port;
> +
> + fp_ops = &rte_event_fp_ops[dev_id];
> + port = fp_ops->data[port_id];
> +
> +#ifdef RTE_LIBRTE_EVENTDEV_DEBUG
> + if (dev_id >= RTE_EVENT_MAX_DEVS || port_id >=
> RTE_EVENT_MAX_PORTS_PER_DEV)
> + return;
> + if (port == NULL)
> + return;
> +#endif
> + rte_eventdev_trace_port_preschedule(dev_id, port_id, type);
> +
> + fp_ops->preschedule(port, type);
> +}
> #ifdef __cplusplus
> }
> #endif
> diff --git a/lib/eventdev/rte_eventdev_core.h
> b/lib/eventdev/rte_eventdev_core.h
> index 2275888a6b..21988abb4f 100644
> --- a/lib/eventdev/rte_eventdev_core.h
> +++ b/lib/eventdev/rte_eventdev_core.h
> @@ -53,6 +53,9 @@ typedef int (*event_preschedule_modify_t)(void *port,
> rte_event_dev_preschedule_type_t
> preschedule_type);
> /**< @internal Modify pre-schedule type on the event port. */
>
> +typedef void (*event_preschedule_t)(void *port,
> rte_event_dev_preschedule_type_t preschedule_type);
> +/**< @internal Issue pre-schedule on an event port. */
> +
> struct __rte_cache_aligned rte_event_fp_ops {
> void **data;
> /**< points to array of internal port data pointers */
> @@ -82,6 +85,8 @@ struct __rte_cache_aligned rte_event_fp_ops {
> /**< PMD Event switch profile function. */
> event_preschedule_modify_t preschedule_modify;
> /**< PMD Event port pre-schedule switch. */
> + event_preschedule_t preschedule;
> + /**< PMD Event port pre-schedule. */
Use reserved not to break ABI
> uintptr_t reserved[4];
> };
