From 48eb03dd26304c24f03bdbb9382e89c8564e71df Mon Sep 17 00:00:00 2001 From: Stanislav Fomichev Date: Mon, 27 Nov 2023 11:03:08 -0800 Subject: xsk: Add TX timestamp and TX checksum offload support This change actually defines the (initial) metadata layout that should be used by AF_XDP userspace (xsk_tx_metadata). The first field is flags which requests appropriate offloads, followed by the offload-specific fields. The supported per-device offloads are exported via netlink (new xsk-flags). The offloads themselves are still implemented in a bit of a framework-y fashion that's left from my initial kfunc attempt. I'm introducing new xsk_tx_metadata_ops which drivers are supposed to implement. The drivers are also supposed to call xsk_tx_metadata_request/xsk_tx_metadata_complete in the right places. Since xsk_tx_metadata_{request,_complete} are static inline, we don't incur any extra overhead doing indirect calls. The benefit of this scheme is as follows: - keeps all metadata layout parsing away from driver code - makes it easy to grep and see which drivers implement what - don't need any extra flags to maintain to keep track of what offloads are implemented; if the callback is implemented - the offload is supported (used by netlink reporting code) Two offloads are defined right now: 1. XDP_TXMD_FLAGS_CHECKSUM: skb-style csum_start+csum_offset 2. XDP_TXMD_FLAGS_TIMESTAMP: writes TX timestamp back into metadata area upon completion (tx_timestamp field) XDP_TXMD_FLAGS_TIMESTAMP is also implemented for XDP_COPY mode: it writes SW timestamp from the skb destructor (note I'm reusing hwtstamps to pass metadata pointer). The struct is forward-compatible and can be extended in the future by appending more fields. Reviewed-by: Song Yoong Siang Signed-off-by: Stanislav Fomichev Acked-by: Jakub Kicinski Link: https://lore.kernel.org/r/20231127190319.1190813-3-sdf@google.com Signed-off-by: Alexei Starovoitov --- tools/net/ynl/generated/netdev-user.c | 19 +++++++++++++++++++ tools/net/ynl/generated/netdev-user.h | 3 +++ 2 files changed, 22 insertions(+) (limited to 'tools/net') diff --git a/tools/net/ynl/generated/netdev-user.c b/tools/net/ynl/generated/netdev-user.c index b5ffe8cd1144..6283d87dad37 100644 --- a/tools/net/ynl/generated/netdev-user.c +++ b/tools/net/ynl/generated/netdev-user.c @@ -58,6 +58,19 @@ const char *netdev_xdp_rx_metadata_str(enum netdev_xdp_rx_metadata value) return netdev_xdp_rx_metadata_strmap[value]; } +static const char * const netdev_xsk_flags_strmap[] = { + [0] = "tx-timestamp", + [1] = "tx-checksum", +}; + +const char *netdev_xsk_flags_str(enum netdev_xsk_flags value) +{ + value = ffs(value) - 1; + if (value < 0 || value >= (int)MNL_ARRAY_SIZE(netdev_xsk_flags_strmap)) + return NULL; + return netdev_xsk_flags_strmap[value]; +} + /* Policies */ struct ynl_policy_attr netdev_dev_policy[NETDEV_A_DEV_MAX + 1] = { [NETDEV_A_DEV_IFINDEX] = { .name = "ifindex", .type = YNL_PT_U32, }, @@ -65,6 +78,7 @@ struct ynl_policy_attr netdev_dev_policy[NETDEV_A_DEV_MAX + 1] = { [NETDEV_A_DEV_XDP_FEATURES] = { .name = "xdp-features", .type = YNL_PT_U64, }, [NETDEV_A_DEV_XDP_ZC_MAX_SEGS] = { .name = "xdp-zc-max-segs", .type = YNL_PT_U32, }, [NETDEV_A_DEV_XDP_RX_METADATA_FEATURES] = { .name = "xdp-rx-metadata-features", .type = YNL_PT_U64, }, + [NETDEV_A_DEV_XSK_FEATURES] = { .name = "xsk-features", .type = YNL_PT_U64, }, }; struct ynl_policy_nest netdev_dev_nest = { @@ -116,6 +130,11 @@ int netdev_dev_get_rsp_parse(const struct nlmsghdr *nlh, void *data) return MNL_CB_ERROR; dst->_present.xdp_rx_metadata_features = 1; dst->xdp_rx_metadata_features = mnl_attr_get_u64(attr); + } else if (type == NETDEV_A_DEV_XSK_FEATURES) { + if (ynl_attr_validate(yarg, attr)) + return MNL_CB_ERROR; + dst->_present.xsk_features = 1; + dst->xsk_features = mnl_attr_get_u64(attr); } } diff --git a/tools/net/ynl/generated/netdev-user.h b/tools/net/ynl/generated/netdev-user.h index 4fafac879df3..39af1908444b 100644 --- a/tools/net/ynl/generated/netdev-user.h +++ b/tools/net/ynl/generated/netdev-user.h @@ -19,6 +19,7 @@ extern const struct ynl_family ynl_netdev_family; const char *netdev_op_str(int op); const char *netdev_xdp_act_str(enum netdev_xdp_act value); const char *netdev_xdp_rx_metadata_str(enum netdev_xdp_rx_metadata value); +const char *netdev_xsk_flags_str(enum netdev_xsk_flags value); /* Common nested types */ /* ============== NETDEV_CMD_DEV_GET ============== */ @@ -50,12 +51,14 @@ struct netdev_dev_get_rsp { __u32 xdp_features:1; __u32 xdp_zc_max_segs:1; __u32 xdp_rx_metadata_features:1; + __u32 xsk_features:1; } _present; __u32 ifindex; __u64 xdp_features; __u32 xdp_zc_max_segs; __u64 xdp_rx_metadata_features; + __u64 xsk_features; }; void netdev_dev_get_rsp_free(struct netdev_dev_get_rsp *rsp); -- cgit v1.2.3