[dpdk-dev] [PATCH v6 0/4] support async dequeue for split ring

[Wenwu Ma <wenwux.ma@intel.com>]

This patch implements asynchronous dequeue data path for split ring.
A new asynchronous dequeue function is introduced. With this function,
the application can try to receive packets from the guest with offloading
large copies to the DMA engine, thus saving precious CPU cycles.

v6:
- Allocate and free packets in bulk.
- struct async_inflight_info aligned to 32 bits.
- Change ASYNC_RX_VHOST to ASYNV_ENQUEUE_VHOST and
  ASYNC_TX_VHOST to ASYNV_DEQUEUE_VHOST.

v5:
- DMA address use IOVA instead of VA.

v4:
- Fix wrong packet index issue in async dequeue improve
  the performance of small packet copies.

v3:
- Fix compilation warning and error in arm platform.
- Restore the removed function virtio_dev_pktmbuf_alloc,
  async dequeue allocate packets in separate.

v2:
- Refactor vhost datapath as preliminary patch for this series.
- The change of using new API in examples/vhost is put into a
  dedicated patch.
- Check queue_id value before using it.
- Async dequeue performance enhancement. 160% performance improvement
  for v2 vs. v1.
- Async dequeue API name change from rte_vhost_try_dequeue_burst to
  rte_vhost_async_try_dequeue_burst.
- The completed package updates the used ring directly.

Wenwu Ma (3):
  examples/vhost: refactor vhost enqueue and dequeue datapaths
  examples/vhost: use a new API to query remaining ring space
  examples/vhost: support vhost async dequeue data path

Yuan Wang (1):
  vhost: support async dequeue for split ring

 doc/guides/prog_guide/vhost_lib.rst |   9 +
 doc/guides/sample_app_ug/vhost.rst  |   9 +-
 examples/vhost/ioat.c               |  67 +++-
 examples/vhost/ioat.h               |  25 ++
 examples/vhost/main.c               | 224 +++++++----
 examples/vhost/main.h               |  33 +-
 examples/vhost/virtio_net.c         |  16 +-
 lib/vhost/rte_vhost_async.h         |  39 +-
 lib/vhost/version.map               |   3 +
 lib/vhost/virtio_net.c              | 586 ++++++++++++++++++++++++++++
 10 files changed, 904 insertions(+), 107 deletions(-)

-- 
2.25.1