Re: [PATCH v2 0/4] eal: update public API to use stdatomic atomics

[Tyler Retzlaff <roretzla@linux.microsoft.com>]

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just a heads up on this series, please defer review until v3 is
submitted.

clang is stricter in atomic type enforcement than gcc so a new revision
is needed that removes the direct use of intrinsics replacing them with
the standard atomics for all _Atomic types.

thanks

On Mon, Jul 31, 2023 at 10:03:50PM -0700, Tyler Retzlaff wrote:
> Update EAL public API to use standard C11 atomics. In accordance with
> technical board discussion February 2023.
> http://mails.dpdk.org/archives/dev/2023-February/263516.html
> 
> This initial series makes no attempt to adapt every use of builtin atomics
> from GCC it intends only to adapt the public API of the EAL presented as
> a compatibility surface to applications.
> 
> Further series will be submitted to adapt the rest of DPDK to use standard
> atomics that are 'internal' and not do not straddle the EAL API.
> 
> The choice has been made to break these two changes apart to allow more
> precise analysis of any potential performance impact this change or
> subsequent changes may introduce.
> 
> Additionally, it is not possible to break the commits up per driver/lib as
> both the provider and consumer of the APIs need to be changed in the same
> commit to maintain non-broken build and function.
> 
> Finally, the first patch in this series is a duplication of Bruce Richardson
> series https://patchwork.dpdk.org/project/dpdk/list/?series=29048 and is
> only being provided to enable the CI run on this series. It is expected that
> Bruce's series when committed will allow the build: require minimum c11 compiler
> here to be dropped from this series.
> 
> v2:
>   * remove volatile qualification from variables, structure fields and
>     parameters that have been qualified _Atomic
>   * restore removal of #include <rte_atomic.h> in rte_ring_core.h the ring
>     library still uses other rte_atomic APIs and types that are not replaced
>     by the standard or compiler intrinsics
>   * add missing adaption to stdatomic in ring/rte_ring_c11_pvt.h
> 
> Tyler Retzlaff (4):
>   build: require minimum c11 compiler
>   devtools: forbid use of GCC atomic builtins
>   eal: adapt rte pause APIs to use C11 atomics
>   eal: adapt rte spinlock and rwlock APIs to use C11 atomics
> 
>  app/test-bbdev/test_bbdev_perf.c         | 123 ++++++++++++++++++++-----------
>  app/test/test_func_reentrancy.c          |   8 +-
>  app/test/test_mcslock.c                  |  12 +--
>  app/test/test_mempool_perf.c             |   8 +-
>  app/test/test_pflock.c                   |  12 +--
>  app/test/test_pmd_perf.c                 |  10 +--
>  app/test/test_ring_perf.c                |   8 +-
>  app/test/test_rwlock.c                   |   8 +-
>  app/test/test_spinlock.c                 |   8 +-
>  app/test/test_stack_perf.c               |  12 +--
>  app/test/test_ticketlock.c               |   8 +-
>  app/test/test_timer.c                    |  16 ++--
>  devtools/checkpatches.sh                 |   8 ++
>  drivers/event/opdl/opdl_ring.c           |  47 ++++++------
>  drivers/net/failsafe/meson.build         |   1 -
>  drivers/net/thunderx/nicvf_rxtx.c        |   5 +-
>  drivers/net/thunderx/nicvf_struct.h      |   2 +-
>  lib/bpf/bpf_pkt.c                        |   4 +-
>  lib/distributor/distributor_private.h    |   2 +-
>  lib/distributor/rte_distributor_single.c |  44 +++++------
>  lib/eal/arm/include/rte_pause_64.h       |  28 +++----
>  lib/eal/common/eal_common_errno.c        |   1 +
>  lib/eal/common/eal_memcfg.h              |   2 +-
>  lib/eal/include/generic/rte_pause.h      |  52 ++++++-------
>  lib/eal/include/generic/rte_rwlock.h     |  46 ++++++------
>  lib/eal/include/generic/rte_spinlock.h   |  21 +++---
>  lib/eal/include/rte_mcslock.h            |  12 +--
>  lib/eal/include/rte_pflock.h             |  22 +++---
>  lib/eal/include/rte_ticketlock.h         |   8 +-
>  lib/eal/loongarch/include/rte_pause.h    |   2 -
>  lib/eal/ppc/include/rte_pause.h          |   2 -
>  lib/eal/riscv/include/rte_pause.h        |   2 -
>  lib/eal/x86/include/rte_spinlock.h       |   2 +-
>  lib/ring/rte_ring_c11_pvt.h              |  28 +++----
>  lib/ring/rte_ring_core.h                 |   4 +-
>  lib/ring/rte_ring_generic_pvt.h          |  19 +++--
>  lib/ring/rte_ring_peek_elem_pvt.h        |   2 +-
>  meson.build                              |   1 +
>  38 files changed, 326 insertions(+), 274 deletions(-)
> 
> -- 
> 1.8.3.1