[v7,00/17] lib/ring: APIs to support custom element size

  The current rte_ring hard-codes the type of the ring element to 'void *',
hence the size of the element is hard-coded to 32b/64b. Since the ring
element type is not an input to rte_ring APIs, it results in couple
of issues:

1) If an application requires to store an element which is not 64b, it
   needs to write its own ring APIs similar to rte_event_ring APIs. This
   creates additional burden on the programmers, who end up making
   work-arounds and often waste memory.
2) If there are multiple libraries that store elements of the same
   type, currently they would have to write their own rte_ring APIs. This
   results in code duplication.

This patch adds new APIs to support configurable ring element size.
The APIs support custom element sizes by allowing to define the ring
element to be a multiple of 32b.

The aim is to achieve same performance as the existing ring
implementation.

The changes to test cases are significant. The patches 3/17 to 15/17
are created to help with the review. Otherwise, they can be quashed
into a single commit.

v7
 - Merged the test cases to test both legacy APIs and rte_ring_xxx_elem APIs
   without code duplication (Konstantin, Olivier)
 - Performance test cases are merged as well (Konstantin, Olivier)
 - Macros to copy elements are converted into inline functions (Olivier)
 - Added back the changes to hash and event libraries

v6
 - Labelled as RFC to indicate the better status
 - Added unit tests to test the rte_ring_xxx_elem APIs
 - Corrected 'macro based partial memcpy' (5/6) patch
 - Added Konstantin's method after correction (6/6)
 - Check Patch shows significant warnings and errors mainly due
   copying code from existing test cases. None of them are harmful.
   I will fix them once we have an agreement.

v5
 - Use memcpy for chunks of 32B (Konstantin).
 - Both 'ring_perf_autotest' and 'ring_perf_elem_autotest' are available
   to compare the results easily.
 - Copying without memcpy is also available in 1/3, if anyone wants to
   experiment on their platform.
 - Added other platform owners to test on their respective platforms.

v4
 - Few fixes after more performance testing

v3
 - Removed macro-fest and used inline functions
   (Stephen, Bruce)

v2
 - Change Event Ring implementation to use ring templates
   (Jerin, Pavan)

Honnappa Nagarahalli (17):
  test/ring: use division for cycle count calculation
  lib/ring: apis to support configurable element size
  test/ring: add functional tests for rte_ring_xxx_elem APIs
  test/ring: test burst APIs with random empty-full test case
  test/ring: add default, single element test cases
  test/ring: rte_ring_xxx_elem test cases for exact size ring
  test/ring: negative test cases for rte_ring_xxx_elem APIs
  test/ring: remove duplicate test cases
  test/ring: removed unused variable synchro
  test/ring: modify single element enq/deq perf test cases
  test/ring: modify burst enq/deq perf test cases
  test/ring: modify bulk enq/deq perf test cases
  test/ring: modify bulk empty deq perf test cases
  test/ring: modify multi-lcore perf test cases
  test/ring: adjust run-on-all-cores perf test cases
  lib/hash: use ring with 32b element size to save memory
  lib/eventdev: use custom element size ring for event rings

 app/test/test_ring.c                 | 1227 +++++++++++---------------
 app/test/test_ring.h                 |  203 +++++
 app/test/test_ring_perf.c            |  434 +++++----
 lib/librte_eventdev/rte_event_ring.c |  147 +--
 lib/librte_eventdev/rte_event_ring.h |   45 +-
 lib/librte_hash/rte_cuckoo_hash.c    |   97 +-
 lib/librte_hash/rte_cuckoo_hash.h    |    2 +-
 lib/librte_ring/Makefile             |    3 +-
 lib/librte_ring/meson.build          |    4 +
 lib/librte_ring/rte_ring.c           |   41 +-
 lib/librte_ring/rte_ring.h           |    1 +
 lib/librte_ring/rte_ring_elem.h      | 1002 +++++++++++++++++++++
 lib/librte_ring/rte_ring_version.map |    2 +
 13 files changed, 2102 insertions(+), 1106 deletions(-)
 create mode 100644 app/test/test_ring.h
 create mode 100644 lib/librte_ring/rte_ring_elem.h