This patch updates the MLX5 PMD and release notes documentations. Adding the guideline for hairpin data buffer size configuration.
Signed-off-by: Bing Zhao <bi...@mellanox.com> Acked-by: Ori Kam <or...@mellanox.com> --- v2: update the range description of hairpin data buffer size v3: correct the minimum value of the range v4: correct some typos and grammatical errors --- doc/guides/nics/mlx5.rst | 16 ++++++++++++++++ doc/guides/rel_notes/release_20_05.rst | 1 + 2 files changed, 17 insertions(+) diff --git a/doc/guides/nics/mlx5.rst b/doc/guides/nics/mlx5.rst index 759d0ac..51b5d47 100644 --- a/doc/guides/nics/mlx5.rst +++ b/doc/guides/nics/mlx5.rst @@ -99,6 +99,7 @@ Features - Support for multiple rte_flow groups. - Per packet no-inline hint flag to disable packet data copying into Tx descriptors. - Hardware LRO. +- Hairpin. Limitations ----------- @@ -786,6 +787,21 @@ Run-time configuration If this parameter is not specified, by default PMD will set the smallest value supported by HW. +- ``hp_buf_log_sz`` parameter [int] + + The total data buffer size of a hairpin queue (logarithmic form), in bytes. + PMD will set the data buffer size to 2 ** ``hp_buf_log_sz``, both for RX & TX. + The capacity of the value is specified by the firmware and the initialization + will get a failure if it is out of scope. + The range of the value is from 11 to 19 right now, and the supported frame + size of a single packet for hairpin is from 512B to 128KB. It might change if + different firmware release is being used. By using a small value, it could + reduce memory consumption but not work with a large frame. If the value is + too large, the memory consumption will be high and some potential performance + degradation will be introduced. + By default, the PMD will set this value to 16, which means that 9KB jumbo + frames will be supported. + .. _mlx5_firmware_config: Firmware configuration diff --git a/doc/guides/rel_notes/release_20_05.rst b/doc/guides/rel_notes/release_20_05.rst index 1e5304d..d43aa2e 100644 --- a/doc/guides/rel_notes/release_20_05.rst +++ b/doc/guides/rel_notes/release_20_05.rst @@ -78,6 +78,7 @@ New Features * Added support for matching on IPv4 Time To Live and IPv6 Hop Limit. * Added support for creating Relaxed Ordering Memory Regions. + * Added support for configuring Hairpin queue data buffer size. * Added support for jumbo frame size (9K MTU) in Multi-Packet RQ mode. * Optimized the memory consumption of flow. -- 1.8.3.1
