This series modernizes the Rx path in the ice driver by removing legacy code and switching to the Page Pool API. The changes follow the same direction as previously done for the iavf driver, and aim to simplify buffer management, improve maintainability, and prepare for future infrastructure reuse.
An important motivation for this work was addressing reports of poor performance in XDP_TX mode when IOMMU is enabled. The legacy Rx model incurred significant overhead due to per-frame DMA mapping, which limited throughput in virtualized environments. This series eliminates those bottlenecks by adopting Page Pool and bi-directional DMA mapping. The first patch removes the legacy Rx path, which relied on manual skb allocation and header copying. This path has become obsolete due to the availability of build_skb() and the increasing complexity of supporting features like XDP and multi-buffer. The second patch drops the page splitting and recycling logic. While once used to optimize memory usage, this logic introduced significant complexity and hotpath overhead. Removing it simplifies the Rx flow and sets the stage for Page Pool adoption. The final patch switches the driver to use the Page Pool and libeth APIs. It also updates the XDP implementation to use libeth_xdp helpers and optimizes XDP_TX by avoiding per-frame DMA mapping. This results in a significant performance improvement in virtualized environments with IOMMU enabled (over 5x gain in XDP_TX throughput). In other scenarios, performance remains on par with the previous implementation. This conversion also aligns with the broader effort to modularize and unify XDP support across Intel Ethernet drivers. Tested on various workloads including netperf and XDP modes (PASS, DROP, TX) with and without IOMMU. No regressions observed. Last but not least, it is suspected that this series may also help mitigate the memory consumption issues recently reported in the driver. For further details, see: https://lore.kernel.org/intel-wired-lan/cak8ffz4hy6gujnenz3wy9jaylzxgfpr7dnzxzgmyoe44car...@mail.gmail.com/ Thanks, Michal Michal Kubiak (3): ice: remove legacy Rx and construct SKB ice: drop page splitting and recycling ice: switch to Page Pool drivers/net/ethernet/intel/Kconfig | 1 + drivers/net/ethernet/intel/ice/ice.h | 3 +- drivers/net/ethernet/intel/ice/ice_base.c | 122 ++-- drivers/net/ethernet/intel/ice/ice_ethtool.c | 22 +- drivers/net/ethernet/intel/ice/ice_lib.c | 1 - drivers/net/ethernet/intel/ice/ice_main.c | 21 +- drivers/net/ethernet/intel/ice/ice_txrx.c | 645 +++--------------- drivers/net/ethernet/intel/ice/ice_txrx.h | 37 +- drivers/net/ethernet/intel/ice/ice_txrx_lib.c | 65 +- drivers/net/ethernet/intel/ice/ice_txrx_lib.h | 7 +- drivers/net/ethernet/intel/ice/ice_virtchnl.c | 5 +- drivers/net/ethernet/intel/ice/ice_xsk.c | 120 +--- drivers/net/ethernet/intel/ice/ice_xsk.h | 6 +- 13 files changed, 205 insertions(+), 850 deletions(-) -- 2.45.2
