On Fri, May 10, 2019 at 04:28:16PM +0000, Eads, Gage wrote: > > -----Original Message----- > > From: Ola Liljedahl [mailto:[email protected]] > > Sent: Friday, May 10, 2019 10:19 AM > > To: [email protected]; Eads, Gage <[email protected]> > > Cc: [email protected]; nd <[email protected]>; Ananyev, Konstantin > > <[email protected]>; [email protected]; Richardson, > > Bruce <[email protected]>; [email protected]; > > [email protected]; Honnappa Nagarahalli > > <[email protected]>; Gavin Hu (Arm Technology China) > > <[email protected]> > > Subject: Re: [dpdk-dev] [PATCH v4] doc: announce ring API change > > > > On Fri, 2019-05-10 at 07:58 -0700, Stephen Hemminger wrote: > > > On Fri, 10 May 2019 14:53:56 +0000 > > > "Eads, Gage" <[email protected]> wrote: > > > > > > 01/02/2019 15:36, Gage Eads: > > > In order to support the non-blocking ring[1], an API change > > > (additional argument to rte_ring_get_memsize()) is required in > > > librte_ring. This commit updates the deprecation notice to pave the > > > way for its inclusion in 19.08. > > > > > > [1] http://mails.dpdk.org/archives/dev/2019-January/124162.html > > > > > > Signed-off-by: Gage Eads <[email protected]> > > > > > > There is still no agreement on this change? > > > > > > > > > Still none. I was hoping this discussion ( > > > http://mails.dpdk.org/archives/dev/2019-April/129229.html) would lead > > > to some clear direction, but at this point the effort is stalled. > > > > > > The fundamental tradeoff is between non-blocking rings and ABI breakage. > > > > It is also possible to do "non-blocking" (but not lock-free) rings with the > > original element size (a pointer per ring slot) as implemented here: > > https://github.com/ARM- > > software/progress64/blob/master/src/p64_ringbuf.c > > Some extra (head&tail) metadata is required but I think there is space for > > that in the rte_ring structure. > > > > > Why not have a new ring type for non-blocking rings since non-blocking > > > rings are not necessary for all use cases. > > > > I proposed a new library ("rte_lfring") with lock-free rings here: > > https://mails.dpdk.org/archives/dev/2019-January/124242.html > > The lock-free design should be the same as in Gage's patch. > > > > rte_lfring could of course be part of the rte_ring library. > > > > Just read through the API/ABI stability discussion > (https://mails.dpdk.org/archives/dev/2019-April/128969.html). I'll drop my > patchset and work on supporting this lfring API instead.
+1 Given the discussions related to ABI stability, it looks better to implement this in another library. Olivier
