Commit eec8359f authored by Taehee Yoo's avatar Taehee Yoo Committed by Jakub Kicinski
Browse files

net: ethtool: add support for configuring hds-thresh 



The hds-thresh option configures the threshold value of
the header-data-split.
If a received packet size is larger than this threshold value, a packet
will be split into header and payload.
The header indicates TCP and UDP header, but it depends on driver spec.
The bnxt_en driver supports HDS(Header-Data-Split) configuration at
FW level, affecting TCP and UDP too.
So, If hds-thresh is set, it affects UDP and TCP packets.

Example:
   # ethtool -G <interface name> hds-thresh <value>

   # ethtool -G enp14s0f0np0 tcp-data-split on hds-thresh 256
   # ethtool -g enp14s0f0np0
   Ring parameters for enp14s0f0np0:
   Pre-set maximums:
   ...
   HDS thresh:  1023
   Current hardware settings:
   ...
   TCP data split:         on
   HDS thresh:  256

The default/min/max values are not defined in the ethtool so the drivers
should define themself.
The 0 value means that all TCP/UDP packets' header and payload
will be split.

Tested-by: default avatarStanislav Fomichev <sdf@fomichev.me>
Signed-off-by: default avatarTaehee Yoo <ap420073@gmail.com>
Link: https://patch.msgid.link/20250114142852.3364986-3-ap420073@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 197258f0

Documentation/netlink/specs/ethtool.yaml

+8 −0
Original line number Diff line number Diff line
@@ -332,6 +332,12 @@ attribute-sets: 
      -

        name: tx-push-buf-len-max

        type: u32

      -

        name: hds-thresh

        type: u32

      -

        name: hds-thresh-max

        type: u32



  -

    name: mm-stat
@@ -1777,6 +1783,8 @@ operations: 
            - rx-push

            - tx-push-buf-len

            - tx-push-buf-len-max

            - hds-thresh

            - hds-thresh-max

      dump: *ring-get-op

    -

      name: rings-set

Documentation/networking/ethtool-netlink.rst

+10 −0
Original line number Diff line number Diff line
@@ -899,6 +899,10 @@ Kernel response contents: 
  ``ETHTOOL_A_RINGS_RX_PUSH``               u8      flag of RX Push mode

  ``ETHTOOL_A_RINGS_TX_PUSH_BUF_LEN``       u32     size of TX push buffer

  ``ETHTOOL_A_RINGS_TX_PUSH_BUF_LEN_MAX``   u32     max size of TX push buffer

  ``ETHTOOL_A_RINGS_HDS_THRESH``            u32     threshold of

                                                    header / data split

  ``ETHTOOL_A_RINGS_HDS_THRESH_MAX``        u32     max threshold of

                                                    header / data split

  =======================================   ======  ===========================



``ETHTOOL_A_RINGS_TCP_DATA_SPLIT`` indicates whether the device is usable with
@@ -941,10 +945,12 @@ Request contents: 
  ``ETHTOOL_A_RINGS_RX_JUMBO``          u32     size of RX jumbo ring

  ``ETHTOOL_A_RINGS_TX``                u32     size of TX ring

  ``ETHTOOL_A_RINGS_RX_BUF_LEN``        u32     size of buffers on the ring

  ``ETHTOOL_A_RINGS_TCP_DATA_SPLIT``    u8      TCP header / data split

  ``ETHTOOL_A_RINGS_CQE_SIZE``          u32     Size of TX/RX CQE

  ``ETHTOOL_A_RINGS_TX_PUSH``           u8      flag of TX Push mode

  ``ETHTOOL_A_RINGS_RX_PUSH``           u8      flag of RX Push mode

  ``ETHTOOL_A_RINGS_TX_PUSH_BUF_LEN``   u32     size of TX push buffer

  ``ETHTOOL_A_RINGS_HDS_THRESH``        u32     threshold of header / data split

  ====================================  ======  ===========================



Kernel checks that requested ring sizes do not exceed limits reported by
@@ -961,6 +967,10 @@ A bigger CQE can have more receive buffer pointers, and in turn the NIC can 
transfer a bigger frame from wire. Based on the NIC hardware, the overall

completion queue size can be adjusted in the driver if CQE size is modified.



``ETHTOOL_A_RINGS_HDS_THRESH`` specifies the threshold value of

header / data split feature. If a received packet size is larger than this

threshold value, header and data will be split.



CHANNELS_GET

============

include/linux/ethtool.h

+9 −0
Original line number Diff line number Diff line
@@ -78,6 +78,9 @@ enum { 
 * @cqe_size: Size of TX/RX completion queue event

 * @tx_push_buf_len: Size of TX push buffer

 * @tx_push_buf_max_len: Maximum allowed size of TX push buffer

 * @hds_thresh: Packet size threshold for header data split (HDS)

 * @hds_thresh_max: Maximum supported setting for @hds_threshold

 *

 */

struct kernel_ethtool_ringparam {

	u32	rx_buf_len;
@@ -87,6 +90,8 @@ struct kernel_ethtool_ringparam { 
	u32	cqe_size;

	u32	tx_push_buf_len;

	u32	tx_push_buf_max_len;

	u32	hds_thresh;

	u32	hds_thresh_max;

};



/**
@@ -97,6 +102,7 @@ struct kernel_ethtool_ringparam { 
 * @ETHTOOL_RING_USE_RX_PUSH: capture for setting rx_push

 * @ETHTOOL_RING_USE_TX_PUSH_BUF_LEN: capture for setting tx_push_buf_len

 * @ETHTOOL_RING_USE_TCP_DATA_SPLIT: capture for setting tcp_data_split

 * @ETHTOOL_RING_USE_HDS_THRS: capture for setting header-data-split-thresh

 */

enum ethtool_supported_ring_param {

	ETHTOOL_RING_USE_RX_BUF_LEN		= BIT(0),
@@ -105,6 +111,7 @@ enum ethtool_supported_ring_param { 
	ETHTOOL_RING_USE_RX_PUSH		= BIT(3),

	ETHTOOL_RING_USE_TX_PUSH_BUF_LEN	= BIT(4),

	ETHTOOL_RING_USE_TCP_DATA_SPLIT		= BIT(5),

	ETHTOOL_RING_USE_HDS_THRS		= BIT(6),

};



#define __ETH_RSS_HASH_BIT(bit)	((u32)1 << (bit))
@@ -1157,6 +1164,7 @@ int ethtool_virtdev_set_link_ksettings(struct net_device *dev, 
 * @rss_ctx:		XArray of custom RSS contexts

 * @rss_lock:		Protects entries in @rss_ctx.  May be taken from

 *			within RTNL.

 * @hds_thresh:		HDS Threshold value.

 * @hds_config:		HDS value from userspace.

 * @wol_enabled:	Wake-on-LAN is enabled

 * @module_fw_flash_in_progress: Module firmware flashing is in progress.
@@ -1164,6 +1172,7 @@ int ethtool_virtdev_set_link_ksettings(struct net_device *dev, 
struct ethtool_netdev_state {

	struct xarray		rss_ctx;

	struct mutex		rss_lock;

	u32			hds_thresh;

	u8			hds_config;

	unsigned		wol_enabled:1;

	unsigned		module_fw_flash_in_progress:1;

include/uapi/linux/ethtool_netlink_generated.h

+2 −0
Original line number Diff line number Diff line
@@ -155,6 +155,8 @@ enum { 
	ETHTOOL_A_RINGS_RX_PUSH,

	ETHTOOL_A_RINGS_TX_PUSH_BUF_LEN,

	ETHTOOL_A_RINGS_TX_PUSH_BUF_LEN_MAX,

	ETHTOOL_A_RINGS_HDS_THRESH,

	ETHTOOL_A_RINGS_HDS_THRESH_MAX,



	__ETHTOOL_A_RINGS_CNT,

	ETHTOOL_A_RINGS_MAX = (__ETHTOOL_A_RINGS_CNT - 1)

net/ethtool/netlink.h

+1 −1
Original line number Diff line number Diff line
@@ -456,7 +456,7 @@ extern const struct nla_policy ethnl_features_set_policy[ETHTOOL_A_FEATURES_WANT 
extern const struct nla_policy ethnl_privflags_get_policy[ETHTOOL_A_PRIVFLAGS_HEADER + 1];

extern const struct nla_policy ethnl_privflags_set_policy[ETHTOOL_A_PRIVFLAGS_FLAGS + 1];

extern const struct nla_policy ethnl_rings_get_policy[ETHTOOL_A_RINGS_HEADER + 1];

extern const struct nla_policy ethnl_rings_set_policy[ETHTOOL_A_RINGS_TX_PUSH_BUF_LEN_MAX + 1];

extern const struct nla_policy ethnl_rings_set_policy[ETHTOOL_A_RINGS_HDS_THRESH_MAX + 1];

extern const struct nla_policy ethnl_channels_get_policy[ETHTOOL_A_CHANNELS_HEADER + 1];

extern const struct nla_policy ethnl_channels_set_policy[ETHTOOL_A_CHANNELS_COMBINED_COUNT + 1];

extern const struct nla_policy ethnl_coalesce_get_policy[ETHTOOL_A_COALESCE_HEADER + 1];