Re: [dpdk-dev] [PATCH v2 0/5] vhost add vectorized data path

["Liu, Yong" <yong.liu@intel.com>]

> -----Original Message-----
> From: Maxime Coquelin <maxime.coquelin@redhat.com>
> Sent: Tuesday, October 6, 2020 9:34 PM
> To: Liu, Yong <yong.liu@intel.com>; Xia, Chenbo <chenbo.xia@intel.com>;
> Wang, Zhihong <zhihong.wang@intel.com>
> Cc: dev@dpdk.org
> Subject: Re: [PATCH v2 0/5] vhost add vectorized data path
> 
> Hi,
> 
> On 9/21/20 8:48 AM, Marvin Liu wrote:
> > Packed ring format is imported since virtio spec 1.1. All descriptors
> > are compacted into one single ring when packed ring format is on. It is
> > straight forward that ring operations can be accelerated by utilizing
> > SIMD instructions.
> >
> > This patch set will introduce vectorized data path in vhost library. If
> > vectorized option is on, operations like descs check, descs writeback,
> > address translation will be accelerated by SIMD instructions. Vhost
> > application can choose whether using vectorized acceleration, it is
> > like external buffer and zero copy features.
> >
> > If platform or ring format not support vectorized function, vhost will
> > fallback to use default batch function. There will be no impact in current
> > data path.
> 
> As a pre-requisite, I'd like some performance numbers in both loopback
> and PVP to figure out if adding such complexity is worth it, given we
> will have to support it for at least one year.
> 


Thanks for suggestion, will add some reference numbers in next version.

> Thanks,
> Maxime
> 
> > v2:
> > * add vIOMMU support
> > * add dequeue offloading
> > * rebase code
> >
> > Marvin Liu (5):
> >   vhost: add vectorized data path
> >   vhost: reuse packed ring functions
> >   vhost: prepare memory regions addresses
> >   vhost: add packed ring vectorized dequeue
> >   vhost: add packed ring vectorized enqueue
> >
> >  doc/guides/nics/vhost.rst           |   5 +
> >  doc/guides/prog_guide/vhost_lib.rst |  12 +
> >  drivers/net/vhost/rte_eth_vhost.c   |  17 +-
> >  lib/librte_vhost/meson.build        |  16 ++
> >  lib/librte_vhost/rte_vhost.h        |   1 +
> >  lib/librte_vhost/socket.c           |   5 +
> >  lib/librte_vhost/vhost.c            |  11 +
> >  lib/librte_vhost/vhost.h            | 235 +++++++++++++++++++
> >  lib/librte_vhost/vhost_user.c       |  11 +
> >  lib/librte_vhost/vhost_vec_avx.c    | 338
> ++++++++++++++++++++++++++++
> >  lib/librte_vhost/virtio_net.c       | 257 ++++-----------------
> >  11 files changed, 692 insertions(+), 216 deletions(-)
> >  create mode 100644 lib/librte_vhost/vhost_vec_avx.c
> >