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author | Daniel T. Lee <danieltimlee@gmail.com> | 2023-01-15 16:16:13 +0900 |
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committer | Alexei Starovoitov <ast@kernel.org> | 2023-01-15 13:32:45 -0800 |
commit | e04946f54cd99fa1bd92e22f4540720d76d88058 (patch) | |
tree | 059e4cedf8d2015617268672584b31c5db88c6ff /samples/bpf/lwt_len_hist.bpf.c | |
parent | e8acf8f47a5d58a00fbfa0f3592bbaaff557cec3 (diff) | |
download | linux-e04946f54cd99fa1bd92e22f4540720d76d88058.tar.gz linux-e04946f54cd99fa1bd92e22f4540720d76d88058.tar.bz2 linux-e04946f54cd99fa1bd92e22f4540720d76d88058.zip |
samples/bpf: change _kern suffix to .bpf with BPF test programs
This commit changes the _kern suffix to .bpf with the BPF test programs.
With this modification, test programs will inherit the benefit of the
new CLANG-BPF compile target.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Link: https://lore.kernel.org/r/20230115071613.125791-11-danieltimlee@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'samples/bpf/lwt_len_hist.bpf.c')
-rw-r--r-- | samples/bpf/lwt_len_hist.bpf.c | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/samples/bpf/lwt_len_hist.bpf.c b/samples/bpf/lwt_len_hist.bpf.c new file mode 100644 index 000000000000..dbab80e813fe --- /dev/null +++ b/samples/bpf/lwt_len_hist.bpf.c @@ -0,0 +1,62 @@ +/* Copyright (c) 2016 Thomas Graf <tgraf@tgraf.ch> + * + * 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 "vmlinux.h" +#include <bpf/bpf_helpers.h> + +struct { + __uint(type, BPF_MAP_TYPE_PERCPU_HASH); + __type(key, u64); + __type(value, u64); + __uint(pinning, LIBBPF_PIN_BY_NAME); + __uint(max_entries, 1024); +} lwt_len_hist_map SEC(".maps"); + +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"; |