[PATCH v6 0/3] Introduce event link profiles

[<pbhagavatula@marvell.com>]

From: Pavan Nikhilesh <pbhagavatula@marvell.com>

A collection of event queues linked to an event port can be associated
with unique identifier called as a link profile, multiple such profiles
can be configured based on the event device capability using the function
`rte_event_port_profile_links_set` which takes arguments similar to
`rte_event_port_link` in addition to the profile identifier.

The maximum link profiles that are supported by an event device is
advertised through the structure member
`rte_event_dev_info::max_profiles_per_port`.

By default, event ports are configured to use the link profile 0 on
initialization.

Once multiple link profiles are set up and the event device is started, the
application can use the function `rte_event_port_profile_switch` to change
the currently active profile on an event port. This effects the next
`rte_event_dequeue_burst` call, where the event queues associated with the
newly active link profile will participate in scheduling.

Rudementary work flow would something like:

Config path:

    uint8_t lq[4] = {4, 5, 6, 7};
    uint8_t hq[4] = {0, 1, 2, 3};

    if (rte_event_dev_info.max_profiles_per_port < 2)
        return -ENOTSUP;

    rte_event_port_profile_links_set(0, 0, hq, NULL, 4, 0);
    rte_event_port_profile_links_set(0, 0, lq, NULL, 4, 1);

Worker path:

    empty_high_deq = 0;
    empty_low_deq = 0;
    is_low_deq = 0;
    while (1) {
        deq = rte_event_dequeue_burst(0, 0, &ev, 1, 0);
        if (deq == 0) {
            /**
             * Change link profile based on work activity on current
             * active profile
             */
            if (is_low_deq) {
                empty_low_deq++;
                if (empty_low_deq == MAX_LOW_RETRY) {
                    rte_event_port_profile_switch(0, 0, 0);
                    is_low_deq = 0;
                    empty_low_deq = 0;
                }
                continue;
            }

            if (empty_high_deq == MAX_HIGH_RETRY) {
                rte_event_port_profile_switch(0, 0, 1);
                is_low_deq = 1;
                empty_high_deq = 0;
            }
            continue;
        }

        // Process the event received.

        if (is_low_deq++ == MAX_LOW_EVENTS) {
            rte_event_port_profile_switch(0, 0, 0);
            is_low_deq = 0;
        }
    }

An application could use heuristic data of load/activity of a given event
port and change its active profile to adapt to the traffic pattern.

An unlink function `rte_event_port_profile_unlink` is provided to
modify the links associated to a profile, and
`rte_event_port_profile_links_get` can be used to retrieve the links
associated with a profile.

Using Link profiles can reduce the overhead of linking/unlinking and
waiting for unlinks in progress in fast-path and gives applications
the ability to switch between preset profiles on the fly.

v6 Changes:
----------
- Fix compilation.

v5 Changes:
----------
- Rebase on next-event

v4 Changes:
----------
- Address review comments (Jerin).

v3 Changes:
----------
- Rebase to next-eventdev
- Rename testcase name to match API.

v2 Changes:
----------
- Fix compilation.

Pavan Nikhilesh (3):
  eventdev: introduce link profiles
  event/cnxk: implement event link profiles
  test/event: add event link profile test

 app/test/test_eventdev.c                  | 117 +++++++++++
 config/rte_config.h                       |   1 +
 doc/guides/eventdevs/cnxk.rst             |   1 +
 doc/guides/eventdevs/features/cnxk.ini    |   3 +-
 doc/guides/eventdevs/features/default.ini |   1 +
 doc/guides/prog_guide/eventdev.rst        |  40 ++++
 doc/guides/rel_notes/release_23_11.rst    |  13 ++
 drivers/common/cnxk/roc_nix_inl_dev.c     |   4 +-
 drivers/common/cnxk/roc_sso.c             |  18 +-
 drivers/common/cnxk/roc_sso.h             |   8 +-
 drivers/common/cnxk/roc_sso_priv.h        |   4 +-
 drivers/event/cnxk/cn10k_eventdev.c       |  45 +++--
 drivers/event/cnxk/cn10k_worker.c         |  11 ++
 drivers/event/cnxk/cn10k_worker.h         |   1 +
 drivers/event/cnxk/cn9k_eventdev.c        |  74 ++++---
 drivers/event/cnxk/cn9k_worker.c          |  22 +++
 drivers/event/cnxk/cn9k_worker.h          |   2 +
 drivers/event/cnxk/cnxk_eventdev.c        |  37 ++--
 drivers/event/cnxk/cnxk_eventdev.h        |  10 +-
 lib/eventdev/eventdev_pmd.h               |  59 +++++-
 lib/eventdev/eventdev_private.c           |   9 +
 lib/eventdev/eventdev_trace.h             |  32 +++
 lib/eventdev/eventdev_trace_points.c      |  12 ++
 lib/eventdev/rte_eventdev.c               | 150 +++++++++++---
 lib/eventdev/rte_eventdev.h               | 231 ++++++++++++++++++++++
 lib/eventdev/rte_eventdev_core.h          |   5 +
 lib/eventdev/rte_eventdev_trace_fp.h      |   8 +
 lib/eventdev/version.map                  |   4 +
 28 files changed, 813 insertions(+), 109 deletions(-)

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2.25.1