<snip> > > Update the incorrect description about atomic operations with provided > wrappers in deprecation doc[1]. > > [1]https://mails.dpdk.org/archives/dev/2021-July/213333.html > > Fixes: 7518c5c4ae6a ("doc: announce adoption of C11 atomic operations > semantics") > Cc: sta...@dpdk.org > > Signed-off-by: Joyce Kong <joyce.k...@arm.com> > Reviewed-by: Ruifeng Wang <ruifeng.w...@arm.com> > --- > doc/guides/rel_notes/deprecation.rst | 16 ++++++++-------- > 1 file changed, 8 insertions(+), 8 deletions(-) > > diff --git a/doc/guides/rel_notes/deprecation.rst > b/doc/guides/rel_notes/deprecation.rst > index 9584d6bfd7..4142315842 100644 > --- a/doc/guides/rel_notes/deprecation.rst > +++ b/doc/guides/rel_notes/deprecation.rst > @@ -19,16 +19,16 @@ Deprecation Notices > > * rte_atomicNN_xxx: These APIs do not take memory order parameter. This > does > not allow for writing optimized code for all the CPU architectures > supported > - in DPDK. DPDK will adopt C11 atomic operations semantics and provide > wrappers > - using C11 atomic built-ins. These wrappers must be used for patches that > - need to be merged in 20.08 onwards. This change will not introduce any > - performance degradation. > + in DPDK. DPDK has adopted atomic operations semantics. GCC atomic > + built-ins must be used for patches that need to be merged in 20.08 > + onwards. This change will not introduce any performance degradation. Since there have been objections to the language used to refer to GCC C11 atomic built-ins, may be we add a reference to the GCC pages?
DPDK has adopted the atomic operations from https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html. These operations must be used for patches that need to be merged in 20.08 onwards. This change will not introduce any performance degradation. > > * rte_smp_*mb: These APIs provide full barrier functionality. However, many > - use cases do not require full barriers. To support such use cases, DPDK > will > - adopt C11 barrier semantics and provide wrappers using C11 atomic built- > ins. > - These wrappers must be used for patches that need to be merged in 20.08 > - onwards. This change will not introduce any performance degradation. > + use cases do not require full barriers. To support such use cases, > + DPDK has adopted atomic barrier semantics. GCC atomic built-ins and a > + new wrapper ``rte_atomic_thread_fence`` instead of > + ``__atomic_thread_fence`` must be used for patches that need to be > + merged in 20.08 onwards. This change will not introduce any performance > degradation. Same here. To support such use cases, DPDK has adopted atomic operations from https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html. A new wrapper ``rte_atomic_thread_fence`` instead of ``__atomic_thread_fence`` must be used for patches that need to be merged in 20.08 onwards. This change will not introduce any performance degradation. > > * lib: will fix extending some enum/define breaking the ABI. There are > multiple > samples in DPDK that enum/define terminated with a ``.*MAX.*`` value > which is > -- > 2.17.1
