This change removes the limitation of having one packet per page in XDP
mode. This has the following implications:
- XDP in Striding RQ mode can now be used on 64K page systems.
- XDP in Legacy RQ mode was using a single packet per page which on 64K
page systems is quite inefficient. The improvement can be observed
with an XDP_DROP test when running in Legacy RQ mode on a ARM
Neoverse-N1 system with a 64K page size:
+-----------------------------------------------+
| MTU | baseline | this change | improvement |
|------+------------+-------------+-------------|
| 1500 | 15.55 Mpps | 18.99 Mpps | 22.0 % |
| 9000 | 15.53 Mpps | 18.24 Mpps | 17.5 % |
+-----------------------------------------------+
After lifting this limitation, the series switches to using fragments
for the side page in non-linear mode. This small improvement is at most
visible for XDP_DROP tests with small 64B packets and a large enough MTU
for Striding RQ to be in non-linear mode:
+----------------------------------------------------------------------+
| System | MTU | baseline | this change | improvement |
|----------------------+------+------------+-------------+-------------|
| 4K page x86_64 [1] | 9000 | 26.30 Mpps | 30.45 Mpps | 15.80 % |
| 64K page aarch64 [2] | 9000 | 15.27 Mpps | 20.10 Mpps | 31.62 % |
+----------------------------------------------------------------------+
This series does not cover the xsk (AF_XDP) paths for 64K page systems.
Dragos Tatulea (5):
net/mlx5e: XSK, Increase size for chunk_size param
net/mlx5e: XDP, Improve dma address calculation of linear part for
XDP_TX
net/mlx5e: XDP, Remove stride size limitation
net/mlx5e: XDP, Use a single linear page per rq
net/mlx5e: XDP, Use page fragments for linear data in multibuf-mode
drivers/net/ethernet/mellanox/mlx5/core/en.h | 12 +++-
.../ethernet/mellanox/mlx5/core/en/params.c | 11 +---
.../ethernet/mellanox/mlx5/core/en/params.h | 2 +-
.../net/ethernet/mellanox/mlx5/core/en/xdp.c | 2 +-
.../net/ethernet/mellanox/mlx5/core/en_main.c | 50 ++++++++++++++--
.../net/ethernet/mellanox/mlx5/core/en_rx.c | 59 +++++++++++++++----
6 files changed, 107 insertions(+), 29 deletions(-)
base-commit: a7fb05cbb8f989fa5a81818be9680464cff9d717
--
2.44.0