[RFC 0/7] regex/hs: introduce Hyperscan regex PMD

[Prudvi Deti]

This RFC series adds a new regexdev PMD based on Hyperscan.

Goal: provide a software regex PMD for environments without regex HW,
while keeping compatibility with the standard ``rte_regexdev`` API.
The PMD is a virtual device, created with ``--vdev=regex_hs`` at EAL
init.

The series introduces:
- a new vdev driver under ``drivers/regex/hs``
- device and queue pair configuration, start/stop/close lifecycle,
  and device dump support
- rule database update, compile+activate, import/export of serialized
  Hyperscan databases
- enqueue/dequeue burst paths with per-queue-pair scratch usage and
  per-queue-pair extended statistics (enqueued/dequeued/matches)
- PMD-private rule flag mappings for common Hyperscan compile options
  (singlematch, prefilter, SOM-leftmost, combination, quiet)

Behavior notes relevant for review:
- per-op match counters are bounded by API field width
  (``nb_matches``/``nb_actual_matches`` are ``uint16_t``)
- payload size exposed through regexdev is ``max_payload_size = 65535``
  bytes, while Hyperscan block mode itself supports larger scan buffers
- queue pairs are intended for single-thread ownership (SPSC model)
  with dedicated scratch per queue pair

Documentation, feature matrix integration, meson integration, and
maintainers metadata are included.

Prudvi Deti (7):
  regex/hs: add driver skeleton and build integration
  regex/hs: add device configure and queue pair setup
  regex/hs: add rule database update and compilation
  regex/hs: add enqueue and dequeue burst paths
  regex/hs: add per-queue-pair extended statistics
  regex/hs: add start stop close and device dump
  regex/hs: add Hyperscan compile flag support

 .mailmap                               |    1 +
 MAINTAINERS                            |    6 +
 doc/guides/regexdevs/features/hs.ini   |    8 +
 doc/guides/regexdevs/hs.rst            |  158 +++
 doc/guides/regexdevs/index.rst         |    1 +
 doc/guides/rel_notes/release_26_11.rst |    7 +
 drivers/regex/hs/hs_regex.c            | 1342 ++++++++++++++++++++++++
 drivers/regex/hs/hs_regex.h            |   89 ++
 drivers/regex/hs/meson.build           |   19 +
 drivers/regex/meson.build              |    1 +
 10 files changed, 1632 insertions(+)
 create mode 100644 doc/guides/regexdevs/features/hs.ini
 create mode 100644 doc/guides/regexdevs/hs.rst
 create mode 100644 drivers/regex/hs/hs_regex.c
 create mode 100644 drivers/regex/hs/hs_regex.h
 create mode 100644 drivers/regex/hs/meson.build

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2.43.0