From: Stephen Hemminger <stephen@networkplumber.org>
To: Bruce Richardson <bruce.richardson@intel.com>
Cc: dev@dpdk.org
Subject: Re: [RFC PATCH 0/6] remove deprecated queue stats
Date: Tue, 23 Sep 2025 08:04:43 -0700 [thread overview]
Message-ID: <20250923080443.5430306c@hermes.local> (raw)
In-Reply-To: <20250923141207.10403-1-bruce.richardson@intel.com>
On Tue, 23 Sep 2025 15:12:00 +0100
Bruce Richardson <bruce.richardson@intel.com> wrote:
> Since DPDK 20.11 release, the use of queue stats inside the rte_eth_stats
> structure has been deprecated with the intention to remove them. Sadly,
> despite 5 years passing that has still not been done. This patchset
> finally attempts to fix that situation and remove the queue stats fields.
>
> The biggest complication here is the fact that, as part of the deprecation,
> a new driver flag was added which caused ethdev to automatically add the
> queue stats into xstats. While this was good, in that it allowed quick use
> of xstats for getting queue statistics, it now causes lots of problems
> because we have 35 drivers (by a rough count using grep) which rely on this
> functionality to export their queue stats via xstats. This means that if we
> drop the queue stats fields from the regular stats structure, then 35
> drivers will lose *all* queue stats reporting functionality! This is not an
> acceptable situation IMHO. [And in one patchset trying to change all 35
> drivers to directly export via xstats is not feasible either, since adding
> extra xstats can be very complicated at times.]
>
> Therefore, we need to make changes that a) removes the queue fields from
> the regular stats structure, while also b) continuing to allow the
> individual driver stats_get functions return those stats to ethdev for
> filling in. I tried a number of approaches here to find one that was most
> feasible to implement for large numbers of drivers, so that either scripts
> or AI assistants could automate a lot of the changes. The most feasible
> approach I found was to define a DPDK-internal queue-stats-only structure,
> which would be passed as a 3rd parameter to the drivers' stats_get
> functions. When calling stats_get from ethdev, this third parameter would
> be NULL, but for gathering xstats, it would be non-NULL for drivers which
> have the RTE_ETH_DEV_AUTOFILL_QUEUE_XSTATS flag set.
>
> For this set, I've separated out the driver changes from the ethdev changes
> and the app changes, since the driver changes are so numerous, making the
> rest hard to review. In order to ensure clean compilation and git history,
> patches 3 through 6 should be squashed into a single one on apply.
>
> Beyond these patches, more cleanup should/could be done:
> * ensure that any drivers which don't set the AUTOFILL flag have the qstats
> parameter set as __rte_unused.
> * For those that do use the AUTOFILL flag, we should ensure that they
> actually do fill in the stats, and not just set them to zero. (First two
> patches here fix that for a couple of Intel drivers)
> * then work to reduce the number of drivers which use the flag to set the
> xstats, with a view to completely removing the queue stats from regular
> stats functions.
> * Within ethdev (and testpmd), we should consider what to do with any other
> legacy queue stats related functions, for example, do we still keep the
> queue mappings functions.
>
>
> Bruce Richardson (6):
> net/ice: don't report empty queue xstats
> net/ipn3ke: drop unsupported per-queue xstats
> ethdev: remove queue stats from ethdev stats structure
> drivers/net: update to remove queue stats from eth stats
> app: remove queue stats from eth stats
> doc: update docs for ethdev changes
>
> app/proc-info/main.c | 16 ---
> app/test-pmd/config.c | 6 -
> app/test/virtual_pmd.c | 3 +-
> config/rte_config.h | 1 -
> doc/guides/rel_notes/deprecation.rst | 7 -
> doc/guides/rel_notes/release_25_11.rst | 6 +
> drivers/net/af_packet/rte_eth_af_packet.c | 13 +-
> drivers/net/af_xdp/rte_eth_af_xdp.c | 35 +++--
> drivers/net/ark/ark_ethdev.c | 36 +++--
> drivers/net/ark/ark_ethdev_rx.c | 14 +-
> drivers/net/ark/ark_ethdev_rx.h | 3 +-
> drivers/net/ark/ark_ethdev_tx.c | 12 +-
> drivers/net/ark/ark_ethdev_tx.h | 3 +-
> drivers/net/atlantic/atl_ethdev.c | 19 +--
> drivers/net/atlantic/atl_types.h | 1 +
> drivers/net/avp/avp_ethdev.c | 20 ++-
> drivers/net/axgbe/axgbe_ethdev.c | 22 +--
> drivers/net/axgbe/axgbe_ethdev.h | 1 +
> drivers/net/bnx2x/bnx2x_ethdev.c | 3 +-
> drivers/net/bnxt/bnxt_reps.c | 14 +-
> drivers/net/bnxt/bnxt_reps.h | 2 +-
> drivers/net/bnxt/bnxt_stats.c | 133 ++++++++++--------
> drivers/net/bnxt/bnxt_stats.h | 2 +-
> drivers/net/bonding/rte_eth_bond_pmd.c | 14 +-
> drivers/net/cnxk/cnxk_ethdev.h | 3 +-
> drivers/net/cnxk/cnxk_rep.h | 3 +-
> drivers/net/cnxk/cnxk_rep_ops.c | 15 +-
> drivers/net/cnxk/cnxk_stats.c | 49 ++++---
> drivers/net/cxgbe/cxgbe_ethdev.c | 3 +-
> drivers/net/cxgbe/cxgbevf_ethdev.c | 3 +-
> drivers/net/dpaa/dpaa_ethdev.c | 3 +-
> drivers/net/dpaa2/dpaa2_ethdev.c | 28 ++--
> drivers/net/ena/ena_ethdev.c | 46 +++---
> drivers/net/enetc/enetc_ethdev.c | 4 +-
> drivers/net/enetfec/enet_ethdev.c | 3 +-
> drivers/net/enic/enic.h | 3 +-
> drivers/net/enic/enic_ethdev.c | 4 +-
> drivers/net/enic/enic_main.c | 3 +-
> drivers/net/enic/enic_vf_representor.c | 3 +-
> drivers/net/failsafe/failsafe_ether.c | 9 --
> drivers/net/failsafe/failsafe_ops.c | 3 +-
> drivers/net/gve/gve_ethdev.c | 4 +-
> drivers/net/hinic/hinic_pmd_ethdev.c | 64 ++++++---
> drivers/net/hns3/hns3_stats.c | 4 +-
> drivers/net/hns3/hns3_stats.h | 3 +-
> drivers/net/intel/cpfl/cpfl_ethdev.c | 3 +-
> drivers/net/intel/e1000/em_ethdev.c | 7 +-
> drivers/net/intel/e1000/igb_ethdev.c | 14 +-
> drivers/net/intel/e1000/igc_ethdev.c | 33 +++--
> drivers/net/intel/fm10k/fm10k_ethdev.c | 27 ++--
> drivers/net/intel/i40e/i40e_ethdev.c | 5 +-
> drivers/net/intel/i40e/i40e_vf_representor.c | 2 +-
> drivers/net/intel/iavf/iavf_ethdev.c | 5 +-
> drivers/net/intel/ice/ice_dcf_ethdev.c | 3 +-
> drivers/net/intel/ice/ice_ethdev.c | 7 +-
> drivers/net/intel/idpf/idpf_ethdev.c | 3 +-
> drivers/net/intel/ipn3ke/ipn3ke_representor.c | 14 +-
> drivers/net/intel/ixgbe/ixgbe_ethdev.c | 29 ++--
> drivers/net/ionic/ionic_ethdev.c | 6 +-
> drivers/net/ionic/ionic_lif.c | 35 +++--
> drivers/net/ionic/ionic_lif.h | 3 +-
> drivers/net/mana/mana.c | 15 +-
> drivers/net/memif/rte_eth_memif.c | 15 +-
> drivers/net/mlx4/mlx4.h | 3 +-
> drivers/net/mlx4/mlx4_ethdev.c | 17 +--
> drivers/net/mlx5/mlx5.h | 3 +-
> drivers/net/mlx5/mlx5_stats.c | 17 +--
> drivers/net/mvneta/mvneta_ethdev.c | 5 +-
> drivers/net/mvpp2/mrvl_ethdev.c | 23 +--
> drivers/net/netvsc/hn_ethdev.c | 17 +--
> drivers/net/netvsc/hn_var.h | 3 +-
> drivers/net/netvsc/hn_vf.c | 3 +-
> drivers/net/nfp/flower/nfp_flower.c | 8 +-
> .../net/nfp/flower/nfp_flower_representor.c | 19 +--
> .../net/nfp/flower/nfp_flower_representor.h | 3 +
> drivers/net/nfp/nfp_net_common.c | 46 +++---
> drivers/net/nfp/nfp_net_common.h | 4 +-
> drivers/net/ngbe/ngbe_ethdev.c | 53 +++----
> drivers/net/ngbe/ngbe_ethdev_vf.c | 5 +-
> drivers/net/ntnic/ntnic_ethdev.c | 22 +--
> drivers/net/null/rte_eth_null.c | 15 +-
> drivers/net/octeon_ep/otx_ep_ethdev.c | 17 ++-
> drivers/net/octeontx/octeontx_ethdev.c | 3 +-
> drivers/net/pcap/pcap_ethdev.c | 23 +--
> drivers/net/pfe/pfe_ethdev.c | 3 +-
> drivers/net/qede/qede_ethdev.c | 23 ++-
> drivers/net/r8169/r8169_ethdev.c | 6 +-
> drivers/net/ring/rte_eth_ring.c | 13 +-
> drivers/net/rnp/rnp_ethdev.c | 15 +-
> drivers/net/sfc/sfc_ethdev.c | 3 +-
> drivers/net/sfc/sfc_repr.c | 3 +-
> drivers/net/tap/rte_eth_tap.c | 23 +--
> drivers/net/thunderx/nicvf_ethdev.c | 27 ++--
> drivers/net/txgbe/txgbe_ethdev.c | 53 +++----
> drivers/net/txgbe/txgbe_ethdev_vf.c | 5 +-
> drivers/net/vhost/rte_eth_vhost.c | 26 ++--
> drivers/net/virtio/virtio_ethdev.c | 23 +--
> drivers/net/vmxnet3/vmxnet3_ethdev.c | 20 +--
> drivers/net/xsc/xsc_ethdev.c | 19 +--
> drivers/net/zxdh/zxdh_ethdev_ops.c | 39 ++---
> drivers/net/zxdh/zxdh_ethdev_ops.h | 3 +-
> lib/ethdev/ethdev_driver.h | 23 ++-
> lib/ethdev/ethdev_private.c | 26 ++++
> lib/ethdev/ethdev_private.h | 2 +
> lib/ethdev/rte_ethdev.c | 37 ++---
> lib/ethdev/rte_ethdev.h | 11 --
> lib/ethdev/rte_ethdev_telemetry.c | 20 +--
> 107 files changed, 898 insertions(+), 706 deletions(-)
>
> --
> 2.48.1
>
There is one thing xstats does not do well. Because xstats is a per-driver
API, there is no uniformity in reporting per-queue information. And if you
take off the auto-fill flag what little information there is will be disappear.
I would propose a new API (and driver callback) to query a single queues
statistics. This would give uniformity across drivers.
But not certain it really matters, have not seen any code that references
the queue counters directly. Maybe somewhere in VPP (doing SNMP??) could care.
The main use of xstats is in debugging and in that case the per-driver
naming is not a big issue.
next prev parent reply other threads:[~2025-09-23 15:04 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-09-23 14:12 Bruce Richardson
2025-09-23 14:12 ` [RFC PATCH 1/6] net/ice: don't report empty queue xstats Bruce Richardson
2025-09-23 14:12 ` [RFC PATCH 2/6] net/ipn3ke: drop unsupported per-queue xstats Bruce Richardson
2025-09-24 1:38 ` Xu, Rosen
2025-09-23 14:12 ` [RFC PATCH 3/6] ethdev: remove queue stats from ethdev stats structure Bruce Richardson
2025-09-24 7:37 ` Morten Brørup
2025-09-24 7:42 ` Bruce Richardson
2025-09-23 14:12 ` [RFC PATCH 4/6] drivers/net: update to remove queue stats from eth stats Bruce Richardson
2025-09-24 1:39 ` Xu, Rosen
2025-09-23 14:12 ` [RFC PATCH 5/6] app: " Bruce Richardson
2025-09-23 14:12 ` [RFC PATCH 6/6] doc: update docs for ethdev changes Bruce Richardson
2025-09-23 15:04 ` Stephen Hemminger [this message]
2025-09-23 15:33 ` [RFC PATCH 0/6] remove deprecated queue stats Bruce Richardson
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20250923080443.5430306c@hermes.local \
--to=stephen@networkplumber.org \
--cc=bruce.richardson@intel.com \
--cc=dev@dpdk.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).