[EXT] Re: [PATCH 2/2] config/arm: disable SVE for cn10k

[Rahul Bhansali]

> -----Original Message-----
> From: fengchengwen <fengchengwen at huawei.com>
> Sent: Friday, May 6, 2022 8:00 AM
> To: Rahul Bhansali <rbhansali at marvell.com>; dev at dpdk.org; Ruifeng Wang
> <ruifeng.wang at arm.com>; Jan Viktorin <viktorin at rehivetech.com>; Bruce
> Richardson <bruce.richardson at intel.com>
> Cc: Jerin Jacob Kollanukkaran <jerinj at marvell.com>
> Subject: [EXT] Re: [PATCH 2/2] config/arm: disable SVE for cn10k
> 
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> 
> ----------------------------------------------------------------------
> On 2022/5/5 22:27, Rahul Bhansali wrote:
> > This disable the SVE flag for cn10k.
> >
> > Performance impact:-
> > With l3fwd example, lpm lookup performance increased by ~21% if Neon
> > is used instead of SVE.
> >
> > Signed-off-by: Rahul Bhansali <rbhansali at marvell.com>
> > ---
> >  config/arm/meson.build | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/config/arm/meson.build b/config/arm/meson.build index
> > dafb342cc6..39b7a1270c 100644
> > --- a/config/arm/meson.build
> > +++ b/config/arm/meson.build
> > @@ -281,7 +281,8 @@ soc_cn10k = {
> >      ],
> >      'part_number': '0xd49',
> >      'extra_march_features': ['crypto'],
> > -    'numa': false
> > +    'numa': false,
> > +    'sve': false
> 
> Suggest remove sve2 flag:
>     '0xd49': {
>         'march': 'armv8.5-a',
>         'march_features': ['sve2'],          ---remove 'sve2'
>         'flags': [
>             ['RTE_MACHINE', '"neoverse-n2"'],
>             ['RTE_ARM_FEATURE_ATOMICS', true],
>             ['RTE_MAX_LCORE', 64],
>             ['RTE_MAX_NUMA_NODES', 1]
>         ]
>     }
> 
If I remove here, then this will also change for " Arm Neoverse N2 soc_n2", because part_number is same, Right ? 
Because of this reason, I thought to have separate flag instead of updating march_features.

> >  }
> >
> >  soc_dpaa = {
> >