[v6,0/4] Add lcore poll busyness telemetry

  Currently, there is no way to measure lcore polling busyness in a passive
way, without any modifications to the application. This patchset adds a new
EAL API that will be able to passively track core polling busyness. As part
of the set, new telemetry endpoints are added to read the generate metrics.

---
v6:
  * Add API and perf unit tests

v5:
  * Fix Windows build
  * Make lcore_telemetry_free() an internal interface
  * Minor cleanup

v4:
  * Fix doc build
  * Rename timestamp macro to RTE_LCORE_POLL_BUSYNESS_TIMESTAMP
  * Make enable/disable read and write atomic
  * Change rte_lcore_poll_busyness_enabled_set() param to bool
  * Move mem alloc from enable/disable to init/cleanup
  * Other minor fixes

v3:
  * Fix missing renaming to poll busyness
  * Fix clang compilation
  * Fix arm compilation

v2:
  * Use rte_get_tsc_hz() to adjust the telemetry period
  * Rename to reflect polling busyness vs general busyness
  * Fix segfault when calling telemetry timestamp from an unregistered
    non-EAL thread.
  * Minor cleanup

Anatoly Burakov (2):
  eal: add lcore poll busyness telemetry
  eal: add cpuset lcore telemetry entries

Kevin Laatz (2):
  app/test: add unit tests for lcore poll busyness
  doc: add howto guide for lcore poll busyness

 app/test/meson.build                        |   4 +
 app/test/test_lcore_poll_busyness_api.c     | 134 ++++++++
 app/test/test_lcore_poll_busyness_perf.c    |  72 ++++
 config/meson.build                          |   1 +
 config/rte_config.h                         |   1 +
 doc/guides/howto/index.rst                  |   1 +
 doc/guides/howto/lcore_poll_busyness.rst    |  93 ++++++
 lib/bbdev/rte_bbdev.h                       |  17 +-
 lib/compressdev/rte_compressdev.c           |   2 +
 lib/cryptodev/rte_cryptodev.h               |   2 +
 lib/distributor/rte_distributor.c           |  21 +-
 lib/distributor/rte_distributor_single.c    |  14 +-
 lib/dmadev/rte_dmadev.h                     |  15 +-
 lib/eal/common/eal_common_lcore_telemetry.c | 350 ++++++++++++++++++++
 lib/eal/common/meson.build                  |   1 +
 lib/eal/include/rte_lcore.h                 |  84 +++++
 lib/eal/linux/eal.c                         |   1 +
 lib/eal/meson.build                         |   3 +
 lib/eal/version.map                         |   7 +
 lib/ethdev/rte_ethdev.h                     |   2 +
 lib/eventdev/rte_eventdev.h                 |  10 +-
 lib/rawdev/rte_rawdev.c                     |   6 +-
 lib/regexdev/rte_regexdev.h                 |   5 +-
 lib/ring/rte_ring_elem_pvt.h                |   1 +
 meson_options.txt                           |   2 +
 25 files changed, 825 insertions(+), 24 deletions(-)
 create mode 100644 app/test/test_lcore_poll_busyness_api.c
 create mode 100644 app/test/test_lcore_poll_busyness_perf.c
 create mode 100644 doc/guides/howto/lcore_poll_busyness.rst
 create mode 100644 lib/eal/common/eal_common_lcore_telemetry.c