From e56fdbfb06e26a7066b070967badef4148528df2 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Sat, 25 Nov 2023 20:31:27 +0100 Subject: bpf: Add link_info support for uprobe multi link Adding support to get uprobe_link details through bpf_link_info interface. Adding new struct uprobe_multi to struct bpf_link_info to carry the uprobe_multi link details. The uprobe_multi.count is passed from user space to denote size of array fields (offsets/ref_ctr_offsets/cookies). The actual array size is stored back to uprobe_multi.count (allowing user to find out the actual array size) and array fields are populated up to the user passed size. All the non-array fields (path/count/flags/pid) are always set. Signed-off-by: Jiri Olsa Signed-off-by: Andrii Nakryiko Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20231125193130.834322-4-jolsa@kernel.org --- tools/include/uapi/linux/bpf.h | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'tools/include/uapi') diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 7a5498242eaa..e88746ba7d21 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -6562,6 +6562,16 @@ struct bpf_link_info { __u32 flags; __u64 missed; } kprobe_multi; + struct { + __aligned_u64 path; + __aligned_u64 offsets; + __aligned_u64 ref_ctr_offsets; + __aligned_u64 cookies; + __u32 path_size; /* in/out: real path size on success, including zero byte */ + __u32 count; /* in/out: uprobe_multi offsets/ref_ctr_offsets/cookies count */ + __u32 flags; + __u32 pid; + } uprobe_multi; struct { __u32 type; /* enum bpf_perf_event_type */ __u32 :32; -- cgit v1.2.3 From 341ac980eab90ac1f6c22ee9f9da83ed9604d899 Mon Sep 17 00:00:00 2001 From: Stanislav Fomichev Date: Mon, 27 Nov 2023 11:03:07 -0800 Subject: xsk: Support tx_metadata_len For zerocopy mode, tx_desc->addr can point to an arbitrary offset and carry some TX metadata in the headroom. For copy mode, there is no way currently to populate skb metadata. Introduce new tx_metadata_len umem config option that indicates how many bytes to treat as metadata. Metadata bytes come prior to tx_desc address (same as in RX case). The size of the metadata has mostly the same constraints as XDP: - less than 256 bytes - 8-byte aligned (compared to 4-byte alignment on xdp, due to 8-byte timestamp in the completion) - non-zero This data is not interpreted in any way right now. Reviewed-by: Song Yoong Siang Signed-off-by: Stanislav Fomichev Reviewed-by: Jakub Kicinski Link: https://lore.kernel.org/r/20231127190319.1190813-2-sdf@google.com Signed-off-by: Alexei Starovoitov --- tools/include/uapi/linux/if_xdp.h | 1 + 1 file changed, 1 insertion(+) (limited to 'tools/include/uapi') diff --git a/tools/include/uapi/linux/if_xdp.h b/tools/include/uapi/linux/if_xdp.h index 73a47da885dc..34411a2e5b6c 100644 --- a/tools/include/uapi/linux/if_xdp.h +++ b/tools/include/uapi/linux/if_xdp.h @@ -76,6 +76,7 @@ struct xdp_umem_reg { __u32 chunk_size; __u32 headroom; __u32 flags; + __u32 tx_metadata_len; }; struct xdp_statistics { -- cgit v1.2.3 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/include/uapi/linux/if_xdp.h | 52 +++++++++++++++++++++++++++++++++++---- tools/include/uapi/linux/netdev.h | 16 ++++++++++++ 2 files changed, 63 insertions(+), 5 deletions(-) (limited to 'tools/include/uapi') diff --git a/tools/include/uapi/linux/if_xdp.h b/tools/include/uapi/linux/if_xdp.h index 34411a2e5b6c..d0882edc1642 100644 --- a/tools/include/uapi/linux/if_xdp.h +++ b/tools/include/uapi/linux/if_xdp.h @@ -26,11 +26,11 @@ */ #define XDP_USE_NEED_WAKEUP (1 << 3) /* By setting this option, userspace application indicates that it can - * handle multiple descriptors per packet thus enabling xsk core to split + * handle multiple descriptors per packet thus enabling AF_XDP to split * multi-buffer XDP frames into multiple Rx descriptors. Without this set - * such frames will be dropped by xsk. + * such frames will be dropped. */ -#define XDP_USE_SG (1 << 4) +#define XDP_USE_SG (1 << 4) /* Flags for xsk_umem_config flags */ #define XDP_UMEM_UNALIGNED_CHUNK_FLAG (1 << 0) @@ -106,6 +106,41 @@ struct xdp_options { #define XSK_UNALIGNED_BUF_ADDR_MASK \ ((1ULL << XSK_UNALIGNED_BUF_OFFSET_SHIFT) - 1) +/* Request transmit timestamp. Upon completion, put it into tx_timestamp + * field of union xsk_tx_metadata. + */ +#define XDP_TXMD_FLAGS_TIMESTAMP (1 << 0) + +/* Request transmit checksum offload. Checksum start position and offset + * are communicated via csum_start and csum_offset fields of union + * xsk_tx_metadata. + */ +#define XDP_TXMD_FLAGS_CHECKSUM (1 << 1) + +/* AF_XDP offloads request. 'request' union member is consumed by the driver + * when the packet is being transmitted. 'completion' union member is + * filled by the driver when the transmit completion arrives. + */ +struct xsk_tx_metadata { + __u64 flags; + + union { + struct { + /* XDP_TXMD_FLAGS_CHECKSUM */ + + /* Offset from desc->addr where checksumming should start. */ + __u16 csum_start; + /* Offset from csum_start where checksum should be stored. */ + __u16 csum_offset; + } request; + + struct { + /* XDP_TXMD_FLAGS_TIMESTAMP */ + __u64 tx_timestamp; + } completion; + }; +}; + /* Rx/Tx descriptor */ struct xdp_desc { __u64 addr; @@ -113,9 +148,16 @@ struct xdp_desc { __u32 options; }; -/* Flag indicating packet constitutes of multiple buffers*/ +/* UMEM descriptor is __u64 */ + +/* Flag indicating that the packet continues with the buffer pointed out by the + * next frame in the ring. The end of the packet is signalled by setting this + * bit to zero. For single buffer packets, every descriptor has 'options' set + * to 0 and this maintains backward compatibility. + */ #define XDP_PKT_CONTD (1 << 0) -/* UMEM descriptor is __u64 */ +/* TX packet carries valid metadata. */ +#define XDP_TX_METADATA (1 << 1) #endif /* _LINUX_IF_XDP_H */ diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h index 2943a151d4f1..48d5477a668c 100644 --- a/tools/include/uapi/linux/netdev.h +++ b/tools/include/uapi/linux/netdev.h @@ -53,12 +53,28 @@ enum netdev_xdp_rx_metadata { NETDEV_XDP_RX_METADATA_MASK = 3, }; +/** + * enum netdev_xsk_flags + * @NETDEV_XSK_FLAGS_TX_TIMESTAMP: HW timestamping egress packets is supported + * by the driver. + * @NETDEV_XSK_FLAGS_TX_CHECKSUM: L3 checksum HW offload is supported by the + * driver. + */ +enum netdev_xsk_flags { + NETDEV_XSK_FLAGS_TX_TIMESTAMP = 1, + NETDEV_XSK_FLAGS_TX_CHECKSUM = 2, + + /* private: */ + NETDEV_XSK_FLAGS_MASK = 3, +}; + enum { NETDEV_A_DEV_IFINDEX = 1, NETDEV_A_DEV_PAD, NETDEV_A_DEV_XDP_FEATURES, NETDEV_A_DEV_XDP_ZC_MAX_SEGS, NETDEV_A_DEV_XDP_RX_METADATA_FEATURES, + NETDEV_A_DEV_XSK_FEATURES, __NETDEV_A_DEV_MAX, NETDEV_A_DEV_MAX = (__NETDEV_A_DEV_MAX - 1) -- cgit v1.2.3 From 11614723af26e7c32fcb704d8f30fdf60c1122dc Mon Sep 17 00:00:00 2001 From: Stanislav Fomichev Date: Mon, 27 Nov 2023 11:03:14 -0800 Subject: xsk: Add option to calculate TX checksum in SW For XDP_COPY mode, add a UMEM option XDP_UMEM_TX_SW_CSUM to call skb_checksum_help in transmit path. Might be useful to debugging issues with real hardware. I also use this mode in the selftests. Signed-off-by: Stanislav Fomichev Link: https://lore.kernel.org/r/20231127190319.1190813-9-sdf@google.com Signed-off-by: Alexei Starovoitov --- tools/include/uapi/linux/if_xdp.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'tools/include/uapi') diff --git a/tools/include/uapi/linux/if_xdp.h b/tools/include/uapi/linux/if_xdp.h index d0882edc1642..638c606dfa74 100644 --- a/tools/include/uapi/linux/if_xdp.h +++ b/tools/include/uapi/linux/if_xdp.h @@ -33,7 +33,13 @@ #define XDP_USE_SG (1 << 4) /* Flags for xsk_umem_config flags */ -#define XDP_UMEM_UNALIGNED_CHUNK_FLAG (1 << 0) +#define XDP_UMEM_UNALIGNED_CHUNK_FLAG (1 << 0) + +/* Force checksum calculation in software. Can be used for testing or + * working around potential HW issues. This option causes performance + * degradation and only works in XDP_COPY mode. + */ +#define XDP_UMEM_TX_SW_CSUM (1 << 1) struct sockaddr_xdp { __u16 sxdp_family; -- cgit v1.2.3