ipv4_csum 60 samples/bpf/xdp_adjust_tail_kern.c static __always_inline void ipv4_csum(void *data_start, int data_size, ipv4_csum 49 tools/testing/selftests/bpf/progs/xdping_kern.c static __always_inline __u16 ipv4_csum(void *data_start, int data_size)