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7cf245a37e
Fix all files in samples/bpf to include libbpf header files with the bpf/
prefix, to be consistent with external users of the library. Also ensure
that all includes of exported libbpf header files (those that are exported
on 'make install' of the library) use bracketed includes instead of quoted.
To make sure no new files are introduced that doesn't include the bpf/
prefix in its include, remove tools/lib/bpf from the include path entirely,
and use tools/lib instead.
Fixes: 6910d7d386 ("selftests/bpf: Ensure bpf_helper_defs.h are taken from selftests dir")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157952560911.1683545.8795966751309534150.stgit@toke.dk
91 lines
2.1 KiB
C
91 lines
2.1 KiB
C
/* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of version 2 of the GNU General Public
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* License as published by the Free Software Foundation.
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*/
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#include <linux/skbuff.h>
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#include <linux/netdevice.h>
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#include <linux/version.h>
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#include <uapi/linux/bpf.h>
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_tracing.h>
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struct bpf_map_def SEC("maps") my_map = {
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.type = BPF_MAP_TYPE_HASH,
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.key_size = sizeof(long),
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.value_size = sizeof(u64),
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.max_entries = 4096,
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};
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/* kprobe is NOT a stable ABI. If kernel internals change this bpf+kprobe
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* example will no longer be meaningful
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*/
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SEC("kprobe/blk_mq_start_request")
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int bpf_prog1(struct pt_regs *ctx)
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{
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long rq = PT_REGS_PARM1(ctx);
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u64 val = bpf_ktime_get_ns();
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bpf_map_update_elem(&my_map, &rq, &val, BPF_ANY);
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return 0;
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}
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static unsigned int log2l(unsigned long long n)
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{
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#define S(k) if (n >= (1ull << k)) { i += k; n >>= k; }
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int i = -(n == 0);
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S(32); S(16); S(8); S(4); S(2); S(1);
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return i;
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#undef S
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}
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#define SLOTS 100
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struct bpf_map_def SEC("maps") lat_map = {
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.type = BPF_MAP_TYPE_PERCPU_ARRAY,
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.key_size = sizeof(u32),
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.value_size = sizeof(u64),
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.max_entries = SLOTS,
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};
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SEC("kprobe/blk_account_io_completion")
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int bpf_prog2(struct pt_regs *ctx)
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{
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long rq = PT_REGS_PARM1(ctx);
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u64 *value, l, base;
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u32 index;
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value = bpf_map_lookup_elem(&my_map, &rq);
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if (!value)
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return 0;
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u64 cur_time = bpf_ktime_get_ns();
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u64 delta = cur_time - *value;
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bpf_map_delete_elem(&my_map, &rq);
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/* the lines below are computing index = log10(delta)*10
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* using integer arithmetic
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* index = 29 ~ 1 usec
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* index = 59 ~ 1 msec
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* index = 89 ~ 1 sec
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* index = 99 ~ 10sec or more
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* log10(x)*10 = log2(x)*10/log2(10) = log2(x)*3
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*/
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l = log2l(delta);
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base = 1ll << l;
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index = (l * 64 + (delta - base) * 64 / base) * 3 / 64;
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if (index >= SLOTS)
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index = SLOTS - 1;
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value = bpf_map_lookup_elem(&lat_map, &index);
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if (value)
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*value += 1;
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return 0;
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}
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char _license[] SEC("license") = "GPL";
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u32 _version SEC("version") = LINUX_VERSION_CODE;
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