[dpdk-dev] [PATCH v2] ring: use aligned memzone allocation

[Ananyev, Konstantin]

> >
> >
> >
> > >
> > > The PROD/CONS_ALIGN values on x86-64 are set to 2 cache lines, so members
> > of struct rte_ring are 128 byte aligned,
> > >and therefore the whole struct needs 128-byte alignment according to the ABI
> > so that the 128-byte alignment of the fields can be guaranteed.
> >
> > Ah ok, missed the fact that rte_ring is 128B aligned these days.
> > BTW, I probably missed the initial discussion, but what was the reason for that?
> > Konstantin
> 
> I don't know why PROD_ALIGN/CONS_ALIGN use 128 byte alignment; it seems unnecessary if the cache line is only 64 bytes.  An alternate
> fix would be to just use cache line alignment for these fields (since memzones are already cache line aligned). 

Yes, had the same thought.

> Maybe there is some deeper  reason for the >= 128-byte alignment logic in rte_ring.h?

Might be, would be good to hear opinion the author of that change. 
Thanks
Konstantin