[dpdk-dev] [RFC v2 0/5] hide eth dev related structures
Konstantin Ananyev
konstantin.ananyev at intel.com
Wed Sep 22 16:09:48 CEST 2021
The aim of these patch series is to make rte_ethdev core data structures
(rte_eth_dev, rte_eth_dev_data, rte_eth_rxtx_callback, etc.) internal to
DPDK and not visible to the user.
That should allow future possible changes to core ethdev related structures
to be transparent to the user and help to improve ABI/API stability.
Note that current ethdev API is preserved, but it is a formal ABI break.
The work is based on previous discussions at:
https://www.mail-archive.com/dev@dpdk.org/msg211405.html
https://www.mail-archive.com/dev@dpdk.org/msg216685.html
and consists of the following main points:
1. Copy public 'fast' function pointers (rx_pkt_burst(), etc.) and
related data pointer from rte_eth_dev into a separate flat array.
We keep it public to still be able to use inline functions for these
'fast' calls (like rte_eth_rx_burst(), etc.) to avoid/minimize slowdown.
Note that apart from function pointers itself, each element of this
flat array also contains two opaque pointers for each ethdev:
1) a pointer to an array of internal queue data pointers
2) points to array of queue callback data pointers.
Note that exposing this extra information allows us to avoid extra
changes inside PMD level, plus should help to avoid possible
performance degradation.
2. Change implementation of 'fast' inline ethdev functions
(rte_eth_rx_burst(), etc.) to use new public flat array.
While it is an ABI breakage, this change is intended to be transparent
for both users (no changes in user app is required) and PMD developers
(no changes in PMD is required).
One extra note - with new implementation RX/TX callback invocation
will cost one extra function call with this changes. That might cause
some slowdown for code-path with RX/TX callbacks heavily involved.
Hope such tradeoff is acceptable for the community.
3. Move rte_eth_dev, rte_eth_dev_data, rte_eth_rxtx_callback and related
things into internal header: <ethdev_driver.h>.
That approach was selected to:
- Avoid(/minimize) possible performance losses.
- Minimize required changes inside PMDs.
Performance testing results (ICX 2.0GHz):
- testpmd macswap fwd mode, plus
a) no RX/TX callbacks:
performance numbers remains the same before and after the patch
b) bpf-load rx 0 0 JM ./dpdk.org/examples/bpf/t3.o:
~2% slowdown
Would like to thank Ferruh and Jerrin for reviewing and testing previous
version of this RFC.
All interested parties please provide your feedback for v2.
If there would be no major objections, I plan to submit a proper v3
patch in next few days.
Konstantin Ananyev (5):
ethdev: allocate max space for internal queue array
ethdev: change input parameters for rx_queue_count
ethdev: copy ethdev 'burst' API into separate structure
ethdev: make burst functions to use new flat array
ethdev: hide eth dev related structures
app/test-pmd/config.c | 23 +-
drivers/common/octeontx2/otx2_sec_idev.c | 2 +-
drivers/crypto/octeontx2/otx2_cryptodev_ops.c | 2 +-
drivers/net/ark/ark_ethdev_rx.c | 4 +-
drivers/net/ark/ark_ethdev_rx.h | 3 +-
drivers/net/atlantic/atl_ethdev.h | 2 +-
drivers/net/atlantic/atl_rxtx.c | 9 +-
drivers/net/bnxt/bnxt_ethdev.c | 8 +-
drivers/net/cxgbe/base/adapter.h | 2 +-
drivers/net/dpaa/dpaa_ethdev.c | 9 +-
drivers/net/dpaa2/dpaa2_ethdev.c | 9 +-
drivers/net/dpaa2/dpaa2_ptp.c | 2 +-
drivers/net/e1000/e1000_ethdev.h | 6 +-
drivers/net/e1000/em_rxtx.c | 4 +-
drivers/net/e1000/igb_rxtx.c | 4 +-
drivers/net/enic/enic_ethdev.c | 12 +-
drivers/net/fm10k/fm10k.h | 2 +-
drivers/net/fm10k/fm10k_rxtx.c | 4 +-
drivers/net/hns3/hns3_rxtx.c | 7 +-
drivers/net/hns3/hns3_rxtx.h | 2 +-
drivers/net/i40e/i40e_rxtx.c | 4 +-
drivers/net/i40e/i40e_rxtx.h | 3 +-
drivers/net/iavf/iavf_rxtx.c | 4 +-
drivers/net/iavf/iavf_rxtx.h | 2 +-
drivers/net/ice/ice_rxtx.c | 4 +-
drivers/net/ice/ice_rxtx.h | 2 +-
drivers/net/igc/igc_txrx.c | 5 +-
drivers/net/igc/igc_txrx.h | 3 +-
drivers/net/ixgbe/ixgbe_ethdev.h | 3 +-
drivers/net/ixgbe/ixgbe_rxtx.c | 4 +-
drivers/net/mlx5/mlx5_rx.c | 26 +-
drivers/net/mlx5/mlx5_rx.h | 2 +-
drivers/net/netvsc/hn_rxtx.c | 4 +-
drivers/net/netvsc/hn_var.h | 3 +-
drivers/net/nfp/nfp_rxtx.c | 4 +-
drivers/net/nfp/nfp_rxtx.h | 3 +-
drivers/net/octeontx2/otx2_ethdev.h | 2 +-
drivers/net/octeontx2/otx2_ethdev_ops.c | 8 +-
drivers/net/sfc/sfc_ethdev.c | 12 +-
drivers/net/thunderx/nicvf_ethdev.c | 3 +-
drivers/net/thunderx/nicvf_rxtx.c | 4 +-
drivers/net/thunderx/nicvf_rxtx.h | 2 +-
drivers/net/txgbe/txgbe_ethdev.h | 3 +-
drivers/net/txgbe/txgbe_rxtx.c | 4 +-
drivers/net/vhost/rte_eth_vhost.c | 4 +-
lib/ethdev/ethdev_driver.h | 152 +++++++++
lib/ethdev/ethdev_private.c | 84 +++++
lib/ethdev/ethdev_private.h | 7 +
lib/ethdev/rte_ethdev.c | 78 +++--
lib/ethdev/rte_ethdev.h | 288 ++++++++++++------
lib/ethdev/rte_ethdev_core.h | 168 +++-------
lib/ethdev/version.map | 6 +
lib/eventdev/rte_event_eth_rx_adapter.c | 2 +-
lib/eventdev/rte_event_eth_tx_adapter.c | 2 +-
lib/eventdev/rte_eventdev.c | 2 +-
55 files changed, 643 insertions(+), 380 deletions(-)
--
2.26.3
More information about the dev
mailing list