[dpdk-dev] [PATCH v7 0/9] add packed ring vectorized path

[Marvin Liu <yong.liu@intel.com>]

This patch set introduced vectorized path for packed ring.

The size of packed ring descriptor is 16Bytes. Four batched descriptors
are just placed into one cacheline. AVX512 instructions can well handle
this kind of data. Packed ring TX path can fully transformed into
vectorized path. Packed ring Rx path can be vectorized when requirements
met(LRO and mergeable disabled).

New option RTE_LIBRTE_VIRTIO_INC_VECTOR will be introduced in this
patch set. This option will unify split and packed ring vectorized
path default setting. Meanwhile user can specify whether enable
vectorized path at runtime by 'vectorized' parameter of virtio user
vdev.

v7:
1. default vectorization is disabled
2. compilation time check with rte_mbuf structure
3. offsets are calcuated when compiling
4. remove useless barrier as descs are batched store&load
5. vindex of scatter is directly set
6. some comments updates
7. enable vectorized path in meson build

v6:
1. fix issue when size not power of 2

v5:
1. remove cpuflags definition as required extensions always come with
   AVX512F on x86_64
2. inorder actions should depend on feature bit
3. check ring type in rx queue setup
4. rewrite some commit logs
5. fix some checkpatch warnings

v4:
1. rename 'packed_vec' to 'vectorized', also used in split ring
2. add RTE_LIBRTE_VIRTIO_INC_VECTOR config for virtio ethdev
3. check required AVX512 extensions cpuflags
4. combine split and packed ring datapath selection logic
5. remove limitation that size must power of two
6. clear 12Bytes virtio_net_hdr

v3:
1. remove virtio_net_hdr array for better performance
2. disable 'packed_vec' by default

v2:
1. more function blocks replaced by vector instructions
2. clean virtio_net_hdr by vector instruction
3. allow header room size change
4. add 'packed_vec' option in virtio_user vdev 
5. fix build not check whether AVX512 enabled
6. doc update


Marvin Liu (9):
  net/virtio: add Rx free threshold setting
  net/virtio: enable vectorized path
  net/virtio: inorder should depend on feature bit
  net/virtio-user: add vectorized path parameter
  net/virtio: add vectorized packed ring Rx path
  net/virtio: reuse packed ring xmit functions
  net/virtio: add vectorized packed ring Tx path
  net/virtio: add election for vectorized path
  doc: add packed vectorized path

 config/common_base                          |   1 +
 doc/guides/nics/virtio.rst                  |  43 +-
 drivers/net/virtio/Makefile                 |  37 ++
 drivers/net/virtio/meson.build              |  15 +
 drivers/net/virtio/virtio_ethdev.c          |  95 ++-
 drivers/net/virtio/virtio_ethdev.h          |   6 +
 drivers/net/virtio/virtio_pci.h             |   3 +-
 drivers/net/virtio/virtio_rxtx.c            | 212 ++-----
 drivers/net/virtio/virtio_rxtx_packed_avx.c | 662 ++++++++++++++++++++
 drivers/net/virtio/virtio_user_ethdev.c     |  37 +-
 drivers/net/virtio/virtqueue.c              |   7 +-
 drivers/net/virtio/virtqueue.h              | 168 ++++-
 12 files changed, 1072 insertions(+), 214 deletions(-)
 create mode 100644 drivers/net/virtio/virtio_rxtx_packed_avx.c

-- 
2.17.1