[PATCH v3 00/27] deprecate rte_atomicNN family

[Stephen Hemminger <stephen@networkplumber.org>]

The rte_atomicNN_* family was flagged for deprecation in 2021 by
commit 3ec965b6de12 ("doc: update atomic operation deprecation")
but enforcement never landed and in-tree usage continued to grow.
v2 covered the EAL changes, lib/ring, and a starter set of drivers.
This series finishes the job: convert every remaining in-tree
caller to the C11-style rte_atomic_*_explicit() / RTE_ATOMIC()
API, then mark the legacy functions __rte_deprecated so future
in-tree and out-of-tree uses are caught at compile time.

Performance: ran the DPDK perf-tests suite (mempool, hash, stack,
ring, distributor, rcu_qsbr, etc.) on the full series; only
lib/ring showed a regression, addressed by the wrapper in patch 03.

Patch organisation
==================

  01-02  EAL: drop the inline-asm fallback paths now that intrinsics
         work on all platforms; reimplement rte_smp_*mb on top of
         rte_atomic_thread_fence.

  03-04  lib/ring and lib/bpf -- the last legacy callers in lib/.

  05-25  Drivers and selftests, one patch per directory.

  26     Suppress deprecation warnings in app/test/test_atomic.c,
         which exercises the legacy API until it goes away.

  27     Mark rte_atomicNN_* with __rte_deprecated and drop the
         corresponding checkpatch grep; new uses are now caught
         at compile time.

Changes since v2
================

Scope: v2 stopped at crypto/ccp (11 patches). v3 adds:

  04        lib/bpf -- the bpf interpreter's atomic op macro
  13-25     Remaining driver/bus/event/vdpa conversions
  26-27     Test-suite warning suppression and the actual
            __rte_deprecated marking

Substantive changes to patches that were in v2:

  02        Also drop the rte_smp_*mb forbidden-token check from
            devtools/checkpatches.sh, since the API is no longer
            on a deprecation cycle.

  03        lib/ring -- keep most of the original code, introduce wrapper
            for the one performance sensitive CAS. This fixes the
            20-30% drop in ring_perf test on x86 which was observed
            when using atomic_compare_exchange_weak_explicit() with GCC.

Feedback wanted
===============

Series is targeting 26.11 rather than the next release.  The driver
conversions touch many maintainers' code and several are likely to
need cycles of review/respin; a longer review window avoids rushing
contested orderings into an earlier release.

  - vmbus producer commit-order pattern (patch 17)
  - the ring CAS wrapper might be improve performance on other similar
    uses of ring buffers in vmbus and netvsc.
  - Dekker-style seq_cst handshake in net/vhost (patch 24), which
    also closes a pre-existing ordering hole on weakly-ordered ISAs
  - netvsc rndis_pending claim/timeout/clear cmpxchg orderings
    (patch 15)

Stephen Hemminger (27):
  eal: use intrinsics for rte_atomic on all platforms
  eal: reimplement rte_smp_*mb with rte_atomic_thread_fence
  ring: use compare-and-swap wrapper
  bpf: replace atomic op macro with typed helpers
  net/bonding: use stdatomic
  net/nbl: remove unused rte_atomic16 field
  net/ena: replace use of rte_atomicNN
  net/failsafe: convert to stdatomic
  net/enic: do not use deprecated rte_atomic64
  net/pfe: use ethdev linkstatus helpers
  net/sfc: replace rte_atomic with stdatomic
  crypto/ccp: replace use of rte_atomic64 with stdatomic
  bus/dpaa: replace rte_atomic16 with stdatomic
  drivers: replace rte_atomic16 with stdatomic
  net/netvsc: replace rte_atomic32 with stdatomic
  event/sw: convert from rte_atomic32 to stdatomic
  bus/vmbus: convert from rte_atomic to stdatomic
  common/dpaax: remove unused atomic macros
  net/bnx2x: convert from rte_atomic32 to stdatomic
  bus/fslmc: replace rte_atomic32 with stdatomic
  drivers/event: replace rte_atomic32 in selftests
  net/hinic: replace rte_atomic32 with stdatomic
  net/txgbe: replace rte_atomic32 with stdatomic
  net/vhost: use stdatomic instead of rte_atomic32
  vdpa/ifc: replace rte_atomic32 with stdatomic
  test/atomic: suppress deprecation warnings for legacy APIs
  eal: mark rte_atomicNN as deprecated

 app/test/test_atomic.c                        |  12 +
 devtools/checkpatches.sh                      |  16 -
 doc/guides/rel_notes/deprecation.rst          |  12 +-
 doc/guides/rel_notes/release_26_07.rst        |   4 +
 drivers/bus/dpaa/base/qbman/qman.c            |   9 +-
 drivers/bus/fslmc/portal/dpaa2_hw_dpbp.c      |  10 +-
 drivers/bus/fslmc/portal/dpaa2_hw_dpci.c      |  10 +-
 drivers/bus/fslmc/portal/dpaa2_hw_dpio.c      |  12 +-
 drivers/bus/fslmc/portal/dpaa2_hw_pvt.h       |   8 +-
 drivers/bus/fslmc/qbman/include/compat.h      |  21 +-
 drivers/bus/vmbus/private.h                   |   2 +-
 drivers/bus/vmbus/vmbus_bufring.c             |  39 ++-
 drivers/common/dpaax/compat.h                 |  14 -
 drivers/crypto/ccp/ccp_crypto.c               |  11 +-
 drivers/crypto/ccp/ccp_crypto.h               |   2 +-
 drivers/crypto/ccp/ccp_dev.c                  |  10 +-
 drivers/crypto/ccp/ccp_dev.h                  |   4 +-
 drivers/event/dpaa2/dpaa2_eventdev_selftest.c |  26 +-
 drivers/event/dpaa2/dpaa2_hw_dpcon.c          |  11 +-
 drivers/event/octeontx/ssovf_evdev_selftest.c |  58 ++--
 drivers/event/sw/sw_evdev.c                   |   8 +-
 drivers/event/sw/sw_evdev.h                   |   4 +-
 drivers/event/sw/sw_evdev_worker.c            |  16 +-
 drivers/net/bnx2x/bnx2x.c                     |   6 +-
 drivers/net/bnx2x/bnx2x.h                     |   2 +-
 drivers/net/bnx2x/ecore_sp.c                  |   6 +-
 drivers/net/bonding/eth_bond_8023ad_private.h |   6 +-
 drivers/net/bonding/rte_eth_bond_8023ad.c     |  35 +-
 drivers/net/ena/base/ena_plat_dpdk.h          |  14 +-
 drivers/net/ena/ena_ethdev.c                  |  21 +-
 drivers/net/ena/ena_ethdev.h                  |   7 +-
 drivers/net/enic/enic.h                       |   6 +-
 drivers/net/enic/enic_compat.h                |   1 -
 drivers/net/enic/enic_main.c                  |  17 +-
 drivers/net/enic/enic_rxtx.c                  |  14 +-
 drivers/net/enic/enic_rxtx_vec_avx2.c         |   4 +-
 drivers/net/failsafe/failsafe_ops.c           |  12 +-
 drivers/net/failsafe/failsafe_private.h       |  29 +-
 drivers/net/failsafe/failsafe_rxtx.c          |   2 +-
 drivers/net/hinic/base/hinic_compat.h         |   2 +-
 drivers/net/hinic/base/hinic_pmd_hwdev.c      |  24 +-
 drivers/net/hinic/base/hinic_pmd_hwdev.h      |   4 +-
 drivers/net/nbl/nbl_hw/nbl_resource.h         |   1 -
 drivers/net/netvsc/hn_rndis.c                 |  28 +-
 drivers/net/netvsc/hn_rxtx.c                  |  12 +-
 drivers/net/netvsc/hn_var.h                   |   6 +-
 drivers/net/pfe/pfe_ethdev.c                  |  32 +-
 drivers/net/sfc/sfc.c                         |   9 +-
 drivers/net/sfc/sfc.h                         |   4 +-
 drivers/net/sfc/sfc_port.c                    |   7 +-
 drivers/net/sfc/sfc_stats.h                   |   2 +-
 drivers/net/txgbe/base/txgbe_mng.c            |   4 +-
 drivers/net/txgbe/base/txgbe_type.h           |   2 +-
 drivers/net/vhost/rte_eth_vhost.c             | 103 +++---
 drivers/vdpa/ifc/ifcvf_vdpa.c                 |  37 +--
 lib/bpf/bpf_exec.c                            |  91 ++++--
 lib/eal/arm/include/rte_atomic_32.h           |  10 -
 lib/eal/arm/include/rte_atomic_64.h           |  10 -
 lib/eal/include/generic/rte_atomic.h          | 305 +++++-------------
 lib/eal/loongarch/include/rte_atomic.h        |  10 -
 lib/eal/ppc/include/rte_atomic.h              | 179 ----------
 lib/eal/riscv/include/rte_atomic.h            |  10 -
 lib/eal/x86/include/rte_atomic.h              | 205 +-----------
 lib/eal/x86/include/rte_atomic_32.h           | 188 -----------
 lib/eal/x86/include/rte_atomic_64.h           | 157 ---------
 lib/ring/rte_ring_generic_pvt.h               |  32 +-
 66 files changed, 585 insertions(+), 1390 deletions(-)

-- 
2.53.0