From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- samples/bpf/lwt_len_hist_kern.c | 75 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 75 insertions(+) create mode 100644 samples/bpf/lwt_len_hist_kern.c (limited to 'samples/bpf/lwt_len_hist_kern.c') diff --git a/samples/bpf/lwt_len_hist_kern.c b/samples/bpf/lwt_len_hist_kern.c new file mode 100644 index 000000000..1fa14c549 --- /dev/null +++ b/samples/bpf/lwt_len_hist_kern.c @@ -0,0 +1,75 @@ +/* Copyright (c) 2016 Thomas Graf + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ + +#include +#include +#include +#include +#include + +struct bpf_elf_map { + __u32 type; + __u32 size_key; + __u32 size_value; + __u32 max_elem; + __u32 flags; + __u32 id; + __u32 pinning; +}; + +struct bpf_elf_map SEC("maps") lwt_len_hist_map = { + .type = BPF_MAP_TYPE_PERCPU_HASH, + .size_key = sizeof(__u64), + .size_value = sizeof(__u64), + .pinning = 2, + .max_elem = 1024, +}; + +static unsigned int log2(unsigned int v) +{ + unsigned int r; + unsigned int shift; + + r = (v > 0xFFFF) << 4; v >>= r; + shift = (v > 0xFF) << 3; v >>= shift; r |= shift; + shift = (v > 0xF) << 2; v >>= shift; r |= shift; + shift = (v > 0x3) << 1; v >>= shift; r |= shift; + r |= (v >> 1); + return r; +} + +static unsigned int log2l(unsigned long v) +{ + unsigned int hi = v >> 32; + if (hi) + return log2(hi) + 32; + else + return log2(v); +} + +SEC("len_hist") +int do_len_hist(struct __sk_buff *skb) +{ + __u64 *value, key, init_val = 1; + + key = log2l(skb->len); + + value = bpf_map_lookup_elem(&lwt_len_hist_map, &key); + if (value) + __sync_fetch_and_add(value, 1); + else + bpf_map_update_elem(&lwt_len_hist_map, &key, &init_val, BPF_ANY); + + return BPF_OK; +} + +char _license[] SEC("license") = "GPL"; -- cgit v1.2.3