[v5,0/7] hide eth dev related structures

  v5 changes:
- Fix spelling (Thomas/David)
- Rename internal helper functions (David)
- Reorder patches and update commit messages (Thomas)
- Update comments (Thomas)
- Changed layout in rte_eth_fp_ops, to group functions and
   related data based on their functionality:
   first 64B line for Rx, second one for Tx.
   Didn't observe any real performance difference comparing to
   original layout. Though decided to keep a new one, as it seems
   a bit more plausible. 

v4 changes:
 - Fix secondary process attach (Pavan)
 - Fix build failure (Ferruh)
 - Update lib/ethdev/verion.map (Ferruh)
   Note that moving newly added symbols from EXPERIMENTAL to DPDK_22
   section makes checkpatch.sh to complain.

v3 changes:
 - Changes in public struct naming (Jerin/Haiyue)
 - Split patches
 - Update docs
 - Shamelessly included Andrew's patch:
   https://patches.dpdk.org/project/dpdk/patch/20210928154856.1015020-1-andrew.rybchenko@oktetlabs.ru/
   into these series.
   I have to do similar thing here, so decided to avoid duplicated effort.

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 trade-off 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, E810 (ice)):
 - testpmd macswap fwd mode, plus
   a) no RX/TX callbacks:
      no actual slowdown observed
   b) bpf-load rx 0 0 JM ./dpdk.org/examples/bpf/t3.o:
      ~2% slowdown
 - l3fwd: no actual slowdown observed

Would like to thank everyone who already reviewed and tested previous
versions of these series. All other interested parties please don't be shy
and provide your feedback.

Andrew Rybchenko (1):
  ethdev: remove legacy Rx descriptor done API

Konstantin Ananyev (6):
  ethdev: allocate max space for internal queue array
  ethdev: change input parameters for rx_queue_count
  ethdev: copy fast-path API into separate structure
  ethdev: make fast-path functions to use new flat array
  ethdev: add API to retrieve multiple ethernet addresses
  ethdev: hide eth dev related structures

 app/test-pmd/config.c                         |  23 +-
 doc/guides/nics/features.rst                  |   6 +-
 doc/guides/rel_notes/deprecation.rst          |   5 -
 doc/guides/rel_notes/release_21_11.rst        |  21 ++
 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              |  10 +-
 drivers/net/e1000/em_ethdev.c                 |   1 -
 drivers/net/e1000/em_rxtx.c                   |  21 +-
 drivers/net/e1000/igb_ethdev.c                |   2 -
 drivers/net/e1000/igb_rxtx.c                  |  21 +-
 drivers/net/enic/enic_ethdev.c                |  12 +-
 drivers/net/fm10k/fm10k.h                     |   5 +-
 drivers/net/fm10k/fm10k_ethdev.c              |   1 -
 drivers/net/fm10k/fm10k_rxtx.c                |  29 +-
 drivers/net/hns3/hns3_rxtx.c                  |   7 +-
 drivers/net/hns3/hns3_rxtx.h                  |   2 +-
 drivers/net/i40e/i40e_ethdev.c                |   1 -
 drivers/net/i40e/i40e_rxtx.c                  |  30 +-
 drivers/net/i40e/i40e_rxtx.h                  |   4 +-
 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_ethdev.c                  |   1 -
 drivers/net/igc/igc_txrx.c                    |  23 +-
 drivers/net/igc/igc_txrx.h                    |   5 +-
 drivers/net/ixgbe/ixgbe_ethdev.c              |   2 -
 drivers/net/ixgbe/ixgbe_ethdev.h              |   5 +-
 drivers/net/ixgbe/ixgbe_rxtx.c                |  22 +-
 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.c           |   1 -
 drivers/net/octeontx2/otx2_ethdev.h           |   3 +-
 drivers/net/octeontx2/otx2_ethdev_ops.c       |  20 +-
 drivers/net/sfc/sfc_ethdev.c                  |  29 +-
 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 +-
 drivers/net/virtio/virtio_ethdev.c            |   1 -
 lib/ethdev/ethdev_driver.h                    | 148 +++++++++
 lib/ethdev/ethdev_private.c                   |  83 +++++
 lib/ethdev/ethdev_private.h                   |   7 +
 lib/ethdev/rte_ethdev.c                       |  89 ++++--
 lib/ethdev/rte_ethdev.h                       | 288 ++++++++++++------
 lib/ethdev/rte_ethdev_core.h                  | 171 +++--------
 lib/ethdev/version.map                        |   8 +-
 lib/eventdev/rte_event_eth_rx_adapter.c       |   2 +-
 lib/eventdev/rte_event_eth_tx_adapter.c       |   2 +-
 lib/eventdev/rte_eventdev.c                   |   2 +-
 lib/metrics/rte_metrics_telemetry.c           |   2 +-
 67 files changed, 677 insertions(+), 564 deletions(-)
  

Hi,

I've reviewed the series, and it looks good to me.
I see we did not introduce new indirect referencing on the datapath
(just replaced rte_eth_devices[] being hidden with the new rte_eth_fp_ops[].)
My only concern - we'll get two places where pointers to the PMDs routines are stored,
and it means potential unsynchro between them, but I do not see the actual scenario for that.
For example, mlx5 PMD proposes multiple tx/rx_burst routines, and actual routine
selection happens on dev_start(), but then it is not supposed to be changed till dev_stop().
The internal PMD checks like this:
"if (dev->rx_pkt_burst == mlx5_rx_burst)"
supposed to continue working OK as well.

Hence, for series:
Acked-by: Viacheslav Ovsiienko <viacheslavo@nvidia.com>

With best regards,
Slava

> -----Original Message-----
> From: Konstantin Ananyev <konstantin.ananyev@intel.com>
> Sent: Thursday, October 7, 2021 14:28
> To: dev@dpdk.org
> Cc: xiaoyun.li@intel.com; anoobj@marvell.com; jerinj@marvell.com;
> ndabilpuram@marvell.com; adwivedi@marvell.com;
> shepard.siegel@atomicrules.com; ed.czeck@atomicrules.com;
> john.miller@atomicrules.com; irusskikh@marvell.com;
> ajit.khaparde@broadcom.com; somnath.kotur@broadcom.com;
> rahul.lakkireddy@chelsio.com; hemant.agrawal@nxp.com;
> sachin.saxena@oss.nxp.com; haiyue.wang@intel.com; johndale@cisco.com;
> hyonkim@cisco.com; qi.z.zhang@intel.com; xiao.w.wang@intel.com;
> humin29@huawei.com; yisen.zhuang@huawei.com; oulijun@huawei.com;
> beilei.xing@intel.com; jingjing.wu@intel.com; qiming.yang@intel.com; Matan
> Azrad <matan@nvidia.com>; Slava Ovsiienko <viacheslavo@nvidia.com>;
> sthemmin@microsoft.com; NBU-Contact-longli <longli@microsoft.com>;
> heinrich.kuhn@corigine.com; kirankumark@marvell.com;
> andrew.rybchenko@oktetlabs.ru; mczekaj@marvell.com;
> jiawenwu@trustnetic.com; jianwang@trustnetic.com;
> maxime.coquelin@redhat.com; chenbo.xia@intel.com; NBU-Contact-Thomas
> Monjalon <thomas@monjalon.net>; ferruh.yigit@intel.com; mdr@ashroe.eu;
> jay.jayatheerthan@intel.com; Konstantin Ananyev
> <konstantin.ananyev@intel.com>
> Subject: [PATCH v5 0/7] hide eth dev related structures
> 
> v5 changes:
> - Fix spelling (Thomas/David)
> - Rename internal helper functions (David)
> - Reorder patches and update commit messages (Thomas)
> - Update comments (Thomas)
> - Changed layout in rte_eth_fp_ops, to group functions and
>    related data based on their functionality:
>    first 64B line for Rx, second one for Tx.
>    Didn't observe any real performance difference comparing to
>    original layout. Though decided to keep a new one, as it seems
>    a bit more plausible.
> 
> v4 changes:
>  - Fix secondary process attach (Pavan)
>  - Fix build failure (Ferruh)
>  - Update lib/ethdev/verion.map (Ferruh)
>    Note that moving newly added symbols from EXPERIMENTAL to DPDK_22
>    section makes checkpatch.sh to complain.
> 
> v3 changes:
>  - Changes in public struct naming (Jerin/Haiyue)
>  - Split patches
>  - Update docs
>  - Shamelessly included Andrew's patch:
>    https://patches.dpdk.org/project/dpdk/patch/20210928154856.1015020-
> 1-andrew.rybchenko@oktetlabs.ru/
>    into these series.
>    I have to do similar thing here, so decided to avoid duplicated effort.
> 
> 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 trade-off 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, E810 (ice)):
>  - testpmd macswap fwd mode, plus
>    a) no RX/TX callbacks:
>       no actual slowdown observed
>    b) bpf-load rx 0 0 JM ./dpdk.org/examples/bpf/t3.o:
>       ~2% slowdown
>  - l3fwd: no actual slowdown observed
> 
> Would like to thank everyone who already reviewed and tested previous
> versions of these series. All other interested parties please don't be shy and
> provide your feedback.
> 
> Andrew Rybchenko (1):
>   ethdev: remove legacy Rx descriptor done API
> 
> Konstantin Ananyev (6):
>   ethdev: allocate max space for internal queue array
>   ethdev: change input parameters for rx_queue_count
>   ethdev: copy fast-path API into separate structure
>   ethdev: make fast-path functions to use new flat array
>   ethdev: add API to retrieve multiple ethernet addresses
>   ethdev: hide eth dev related structures
> 
>  app/test-pmd/config.c                         |  23 +-
>  doc/guides/nics/features.rst                  |   6 +-
>  doc/guides/rel_notes/deprecation.rst          |   5 -
>  doc/guides/rel_notes/release_21_11.rst        |  21 ++
>  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              |  10 +-
>  drivers/net/e1000/em_ethdev.c                 |   1 -
>  drivers/net/e1000/em_rxtx.c                   |  21 +-
>  drivers/net/e1000/igb_ethdev.c                |   2 -
>  drivers/net/e1000/igb_rxtx.c                  |  21 +-
>  drivers/net/enic/enic_ethdev.c                |  12 +-
>  drivers/net/fm10k/fm10k.h                     |   5 +-
>  drivers/net/fm10k/fm10k_ethdev.c              |   1 -
>  drivers/net/fm10k/fm10k_rxtx.c                |  29 +-
>  drivers/net/hns3/hns3_rxtx.c                  |   7 +-
>  drivers/net/hns3/hns3_rxtx.h                  |   2 +-
>  drivers/net/i40e/i40e_ethdev.c                |   1 -
>  drivers/net/i40e/i40e_rxtx.c                  |  30 +-
>  drivers/net/i40e/i40e_rxtx.h                  |   4 +-
>  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_ethdev.c                  |   1 -
>  drivers/net/igc/igc_txrx.c                    |  23 +-
>  drivers/net/igc/igc_txrx.h                    |   5 +-
>  drivers/net/ixgbe/ixgbe_ethdev.c              |   2 -
>  drivers/net/ixgbe/ixgbe_ethdev.h              |   5 +-
>  drivers/net/ixgbe/ixgbe_rxtx.c                |  22 +-
>  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.c           |   1 -
>  drivers/net/octeontx2/otx2_ethdev.h           |   3 +-
>  drivers/net/octeontx2/otx2_ethdev_ops.c       |  20 +-
>  drivers/net/sfc/sfc_ethdev.c                  |  29 +-
>  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 +-
>  drivers/net/virtio/virtio_ethdev.c            |   1 -
>  lib/ethdev/ethdev_driver.h                    | 148 +++++++++
>  lib/ethdev/ethdev_private.c                   |  83 +++++
>  lib/ethdev/ethdev_private.h                   |   7 +
>  lib/ethdev/rte_ethdev.c                       |  89 ++++--
>  lib/ethdev/rte_ethdev.h                       | 288 ++++++++++++------
>  lib/ethdev/rte_ethdev_core.h                  | 171 +++--------
>  lib/ethdev/version.map                        |   8 +-
>  lib/eventdev/rte_event_eth_rx_adapter.c       |   2 +-
>  lib/eventdev/rte_event_eth_tx_adapter.c       |   2 +-
>  lib/eventdev/rte_eventdev.c                   |   2 +-
>  lib/metrics/rte_metrics_telemetry.c           |   2 +-
>  67 files changed, 677 insertions(+), 564 deletions(-)
> 
> --
> 2.26.3
  

Hi Konstantin,

On 10/7/21 2:27 PM, Konstantin Ananyev wrote:
> v5 changes:
> - Fix spelling (Thomas/David)
> - Rename internal helper functions (David)
> - Reorder patches and update commit messages (Thomas)
> - Update comments (Thomas)
> - Changed layout in rte_eth_fp_ops, to group functions and
>    related data based on their functionality:
>    first 64B line for Rx, second one for Tx.
>    Didn't observe any real performance difference comparing to
>    original layout. Though decided to keep a new one, as it seems
>    a bit more plausible. 
> 
> v4 changes:
>  - Fix secondary process attach (Pavan)
>  - Fix build failure (Ferruh)
>  - Update lib/ethdev/verion.map (Ferruh)
>    Note that moving newly added symbols from EXPERIMENTAL to DPDK_22
>    section makes checkpatch.sh to complain.
> 
> v3 changes:
>  - Changes in public struct naming (Jerin/Haiyue)
>  - Split patches
>  - Update docs
>  - Shamelessly included Andrew's patch:
>    https://patches.dpdk.org/project/dpdk/patch/20210928154856.1015020-1-andrew.rybchenko@oktetlabs.ru/
>    into these series.
>    I have to do similar thing here, so decided to avoid duplicated effort.
> 
> 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 trade-off 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, E810 (ice)):
>  - testpmd macswap fwd mode, plus
>    a) no RX/TX callbacks:
>       no actual slowdown observed
>    b) bpf-load rx 0 0 JM ./dpdk.org/examples/bpf/t3.o:
>       ~2% slowdown
>  - l3fwd: no actual slowdown observed
> 
> Would like to thank everyone who already reviewed and tested previous
> versions of these series. All other interested parties please don't be shy
> and provide your feedback.

Many thanks for the very good patch series.
I hope we'll make it to be included in 21.11.
If you need any help with cosmetic fixes suggested
by me on review, please, let me know.

Andrew.