From: Honnappa Nagarahalli Date: Fri, 22 May 2020 04:30:13 +0000 (-0500) Subject: doc: announce adoption of C11 atomic operations semantics X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=7518c5c4ae6a3b24ffa5a127895ca7f6921361ba;p=dpdk.git doc: announce adoption of C11 atomic operations semantics As agreed in the DPDK tech board [1], after 20.05 release, patches must use C11 atomic operations semantics with the help of wrappers. [1] http://mails.dpdk.org/archives/dev/2020-April/165143.html Signed-off-by: Honnappa Nagarahalli Reviewed-by: Phil Yang Reviewed-by: Ruifeng Wang Acked-by: Hemant Agrawal Acked-by: Jerin Jacob Acked-by: David Christensen Acked-by: Konstantin Ananyev --- diff --git a/doc/guides/rel_notes/deprecation.rst b/doc/guides/rel_notes/deprecation.rst index 2e2ed92eef..2d11bae935 100644 --- a/doc/guides/rel_notes/deprecation.rst +++ b/doc/guides/rel_notes/deprecation.rst @@ -38,6 +38,19 @@ Deprecation Notices remove it from the externally visible ABI and allow it to be updated in the future. +* 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. + +* 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. + * igb_uio: In the view of reducing the kernel dependency from the main tree, as a first step, the Technical Board decided to move ``igb_uio`` kernel module to the dpdk-kmods repository in the /linux/igb_uio/ directory