diff options
Diffstat (limited to 'Documentation/networking/af_xdp.rst')
| -rw-r--r-- | Documentation/networking/af_xdp.rst | 38 |
1 files changed, 19 insertions, 19 deletions
diff --git a/Documentation/networking/af_xdp.rst b/Documentation/networking/af_xdp.rst index 2ccc5644cc98..60b217b436be 100644 --- a/Documentation/networking/af_xdp.rst +++ b/Documentation/networking/af_xdp.rst @@ -243,8 +243,8 @@ Configuration Flags and Socket Options These are the various configuration flags that can be used to control and monitor the behavior of AF_XDP sockets. -XDP_COPY and XDP_ZERO_COPY bind flags -------------------------------------- +XDP_COPY and XDP_ZEROCOPY bind flags +------------------------------------ When you bind to a socket, the kernel will first try to use zero-copy copy. If zero-copy is not supported, it will fall back on using copy @@ -252,7 +252,7 @@ mode, i.e. copying all packets out to user space. But if you would like to force a certain mode, you can use the following flags. If you pass the XDP_COPY flag to the bind call, the kernel will force the socket into copy mode. If it cannot use copy mode, the bind call will -fail with an error. Conversely, the XDP_ZERO_COPY flag will force the +fail with an error. Conversely, the XDP_ZEROCOPY flag will force the socket into zero-copy mode or fail. XDP_SHARED_UMEM bind flag @@ -290,19 +290,19 @@ round-robin example of distributing packets is shown below: #define MAX_SOCKS 16 struct { - __uint(type, BPF_MAP_TYPE_XSKMAP); - __uint(max_entries, MAX_SOCKS); - __uint(key_size, sizeof(int)); - __uint(value_size, sizeof(int)); + __uint(type, BPF_MAP_TYPE_XSKMAP); + __uint(max_entries, MAX_SOCKS); + __uint(key_size, sizeof(int)); + __uint(value_size, sizeof(int)); } xsks_map SEC(".maps"); static unsigned int rr; SEC("xdp_sock") int xdp_sock_prog(struct xdp_md *ctx) { - rr = (rr + 1) & (MAX_SOCKS - 1); + rr = (rr + 1) & (MAX_SOCKS - 1); - return bpf_redirect_map(&xsks_map, rr, XDP_DROP); + return bpf_redirect_map(&xsks_map, rr, XDP_DROP); } Note, that since there is only a single set of FILL and COMPLETION @@ -379,7 +379,7 @@ would look like this for the TX path: .. code-block:: c if (xsk_ring_prod__needs_wakeup(&my_tx_ring)) - sendto(xsk_socket__fd(xsk_handle), NULL, 0, MSG_DONTWAIT, NULL, 0); + sendto(xsk_socket__fd(xsk_handle), NULL, 0, MSG_DONTWAIT, NULL, 0); I.e., only use the syscall if the flag is set. @@ -442,9 +442,9 @@ purposes. The supported statistics are shown below: .. code-block:: c struct xdp_statistics { - __u64 rx_dropped; /* Dropped for reasons other than invalid desc */ - __u64 rx_invalid_descs; /* Dropped due to invalid descriptor */ - __u64 tx_invalid_descs; /* Dropped due to invalid descriptor */ + __u64 rx_dropped; /* Dropped for reasons other than invalid desc */ + __u64 rx_invalid_descs; /* Dropped due to invalid descriptor */ + __u64 tx_invalid_descs; /* Dropped due to invalid descriptor */ }; XDP_OPTIONS getsockopt @@ -483,15 +483,15 @@ like this: .. code-block:: c // struct xdp_rxtx_ring { - // __u32 *producer; - // __u32 *consumer; - // struct xdp_desc *desc; + // __u32 *producer; + // __u32 *consumer; + // struct xdp_desc *desc; // }; // struct xdp_umem_ring { - // __u32 *producer; - // __u32 *consumer; - // __u64 *desc; + // __u32 *producer; + // __u32 *consumer; + // __u64 *desc; // }; // typedef struct xdp_rxtx_ring RING; |