kernel/linux.git/net/ethtool/rings.c, branch v6.18.21

net: ethtool: fix ioctl confusing drivers about desired HDS user config

2025-02-24T22:15:42+00:00

The legacy ioctl path does not have support for extended attributes. So we issue a GET to fetch the current settings from the driver, in an attempt to keep them unchanged. HDS is a bit "special" as the GET only returns on/off while the SET takes a "ternary" argument (on/off/default). If the driver was in the "default" setting - executing the ioctl path binds it to on or off, even tho the user did not intend to change HDS config. Factor the relevant logic out of the netlink code and reuse it. Fixes: 87c8f8496a05 ("bnxt_en: add support for tcp-data-split ethtool command") Acked-by: Stanislav Fomichev Tested-by: Daniel Xu Tested-by: Taehee Yoo Link: https://patch.msgid.link/20250221025141.1132944-1-kuba@kernel.org Signed-off-by: Jakub Kicinski

net: ethtool: populate the default HDS params in the core

2025-01-20T19:44:58+00:00

The core has the current HDS config, it can pre-populate the values for the drivers. While at it, remove the zero-setting in netdevsim. Zero are the default values since the config is zalloc'ed. Reviewed-by: Michael Chan Link: https://patch.msgid.link/20250119020518.1962249-6-kuba@kernel.org Signed-off-by: Jakub Kicinski

net: provide pending ring configuration in net_device

2025-01-20T19:44:57+00:00

Record the pending configuration in net_device struct. ethtool core duplicates the current config and the specific handlers (for now just ringparam) can modify it. Reviewed-by: Michael Chan Link: https://patch.msgid.link/20250119020518.1962249-4-kuba@kernel.org Signed-off-by: Jakub Kicinski

net: move HDS config from ethtool state

2025-01-20T19:44:57+00:00

Separate the HDS config from the ethtool state struct. The HDS config contains just simple parameters, not state. Having it as a separate struct will make it easier to clone / copy and also long term potentially make it per-queue. Reviewed-by: Michael Chan Link: https://patch.msgid.link/20250119020518.1962249-2-kuba@kernel.org Signed-off-by: Jakub Kicinski

net: ethtool: add ring parameter filtering

2025-01-15T22:42:11+00:00

While the devmem is running, the tcp-data-split and hds-thresh configuration should not be changed. If user tries to change tcp-data-split and threshold value while the devmem is running, it fails and shows extack message. Reviewed-by: Jakub Kicinski Tested-by: Stanislav Fomichev Reviewed-by: Mina Almasry Signed-off-by: Taehee Yoo Link: https://patch.msgid.link/20250114142852.3364986-5-ap420073@gmail.com Signed-off-by: Jakub Kicinski

net: ethtool: add support for configuring hds-thresh

2025-01-15T22:42:11+00:00

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 hds-thresh # 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: Stanislav Fomichev Signed-off-by: Taehee Yoo Link: https://patch.msgid.link/20250114142852.3364986-3-ap420073@gmail.com Signed-off-by: Jakub Kicinski

net: ethtool: add hds_config member in ethtool_netdev_state

2025-01-15T22:42:11+00:00

When tcp-data-split is UNKNOWN mode, drivers arbitrarily handle it. For example, bnxt_en driver automatically enables if at least one of LRO/GRO/JUMBO is enabled. If tcp-data-split is UNKNOWN and LRO is enabled, a driver returns ENABLES of tcp-data-split, not UNKNOWN. So, `ethtool -g eth0` shows tcp-data-split is enabled. The problem is in the setting situation. In the ethnl_set_rings(), it first calls get_ringparam() to get the current driver's config. At that moment, if driver's tcp-data-split config is UNKNOWN, it returns ENABLE if LRO/GRO/JUMBO is enabled. Then, it sets values from the user and driver's current config to kernel_ethtool_ringparam. Last it calls .set_ringparam(). The driver, especially bnxt_en driver receives ETHTOOL_TCP_DATA_SPLIT_ENABLED. But it can't distinguish whether it is set by the user or just the current config. When user updates ring parameter, the new hds_config value is updated and current hds_config value is stored to old_hdsconfig. Driver's .set_ringparam() callback can distinguish a passed tcp-data-split value is came from user explicitly. If .set_ringparam() is failed, hds_config is rollbacked immediately. Suggested-by: Jakub Kicinski Reviewed-by: Jakub Kicinski Signed-off-by: Taehee Yoo Link: https://patch.msgid.link/20250114142852.3364986-2-ap420073@gmail.com Signed-off-by: Jakub Kicinski

ethtool: add SET for TCP_DATA_SPLIT ringparam

2023-12-14T02:22:02+00:00

Follow up commit 9690ae604290 ("ethtool: add header/data split indication") and add the set part of Ethtool's header split, i.e. ability to enable/disable header split via the Ethtool Netlink interface. This might be helpful to optimize the setup for particular workloads, for example, to avoid XDP frags, and so on. A driver should advertise ``ETHTOOL_RING_USE_TCP_DATA_SPLIT`` in its ops->supported_ring_params to allow doing that. "Unknown" passed from the userspace when the header split is supported means the driver is free to choose the preferred state. Reviewed-by: Przemek Kitszel Signed-off-by: Alexander Lobakin Link: https://lore.kernel.org/r/20231212142752.935000-2-aleksander.lobakin@intel.com Signed-off-by: Jakub Kicinski

ethtool: netlink: always pass genl_info to .prepare_data

2023-08-15T22:01:03+00:00

We had a number of bugs in the past because developers forgot to fully test dumps, which pass NULL as info to .prepare_data. .prepare_data implementations would try to access info->extack leading to a null-deref. Now that dumps and notifications can access struct genl_info we can pass it in, and remove the info null checks. Reviewed-by: Vladimir Oltean Tested-by: Vladimir Oltean # pause Reviewed-by: Jiri Pirko Link: https://lore.kernel.org/r/20230814214723.2924989-11-kuba@kernel.org Signed-off-by: Jakub Kicinski

ethtool: Add support for configuring tx_push_buf_len

2023-03-28T02:49:58+00:00

This attribute, which is part of ethtool's ring param configuration allows the user to specify the maximum number of the packet's payload that can be written directly to the device. Example usage: # ethtool -G [interface] tx-push-buf-len [number of bytes] Co-developed-by: Jakub Kicinski Signed-off-by: Shay Agroskin Signed-off-by: Jakub Kicinski