Re: [PATCH v4 1/4] doc: announce new cpu flag added to rte_cpu_flag_t

[David Marchand <david.marchand@redhat.com>]

On Tue, Apr 18, 2023 at 11:22 AM Bruce Richardson
<bruce.richardson@intel.com> wrote:
>
> On Tue, Apr 18, 2023 at 09:52:49AM +0100, Ferruh Yigit wrote:
> > On 4/18/2023 9:25 AM, Sivaprasad Tummala wrote:
> > > A new flag RTE_CPUFLAG_MONITORX is added to rte_cpu_flag_t in
> > > DPDK 23.07 release to support monitorx instruction on EPYC processors.
> > > This results in ABI breakage for legacy apps.
> > >
> > > Signed-off-by: Sivaprasad Tummala <sivaprasad.tummala@amd.com>
> > > ---
> > >  doc/guides/rel_notes/deprecation.rst | 3 +++
> > >  1 file changed, 3 insertions(+)
> > >
> > > diff --git a/doc/guides/rel_notes/deprecation.rst b/doc/guides/rel_notes/deprecation.rst
> > > index dcc1ca1696..831713983f 100644
> > > --- a/doc/guides/rel_notes/deprecation.rst
> > > +++ b/doc/guides/rel_notes/deprecation.rst
> > > @@ -163,3 +163,6 @@ Deprecation Notices
> > >    The new port library API (functions rte_swx_port_*)
> > >    will gradually transition from experimental to stable status
> > >    starting with DPDK 23.07 release.
> > > +
> > > +* eal/x86: The enum ``rte_cpu_flag_t`` will be extended with a new cpu flag
> > > +  ``RTE_CPUFLAG_MONITORX`` to support monitorx instruction on EPYC processors.

There is no need for announcing an addition.
The problem is moving/removing other elements of an enum.


> >
> >
> > OK to add new CPU flag,
> > Acked-by: Ferruh Yigit <ferruh.yigit@amd.com>
> >
> >
> > But @David, @Bruce, is it OK to break ABI whenever a new CPU flag is
> > added, should we hide CPU flags better?
> >
> > Or other option can be drop the 'RTE_CPUFLAG_NUMFLAGS' and allow
> > appending new flags to the end although this may lead enum become more
> > messy by time.
>
> +1 top drop the NUMFLAGS value. We should not break ABI each time we need a
> new flag.

+1.
So in 23.07 we need an announce for this removal to happen in 23.11.


-- 
David Marchand