[PATCH 0/5] ring: convert to C11 atomics where practical

[Stephen Hemminger <stephen@networkplumber.org>]

This is split out from the atomic deprecation series.
Convert lib/ring off rte_atomic32 and onto the C11 memory model,
except where C11 version has noticable performance drop
on x86 with GCC.

The pre-existing C11 and GCC-builtin paths lived in separate headers
with substantial duplication.  After this series, only the MP head
CAS (__rte_ring_headtail_move_head_mt) retains separate implementations;
everything else is shared.  Patch 2 documents the reason for
keeping the GCC builtin on the MP head CAS.

The default RTE_USE_C11_MEM_MODEL selection per architecture is unchanged.

Stephen Hemminger (5):
  ring: split single thread vs multi-thread cases
  ring: use GCC builtin as alternative to rte_atomic32
  ring: use C11 for update_tail
  ring: drop unused arg to update_tail
  ring: use C11 for single thread move head

 lib/ring/meson.build                          |   2 +-
 lib/ring/rte_ring_c11_pvt.h                   |  61 +++------
 lib/ring/rte_ring_elem_pvt.h                  | 116 ++++++++++++++++--
 ..._ring_generic_pvt.h => rte_ring_gcc_pvt.h} |  62 +++-------
 lib/ring/rte_ring_hts_elem_pvt.h              |   8 +-
 lib/ring/soring.c                             |  34 ++---
 6 files changed, 161 insertions(+), 122 deletions(-)
 rename lib/ring/{rte_ring_generic_pvt.h => rte_ring_gcc_pvt.h} (63%)

-- 
2.53.0