forked from Minki/linux
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
100 lines
2.1 KiB
C
100 lines
2.1 KiB
C
/* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com
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* Copyright (c) 2015 BMW Car IT GmbH
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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/version.h>
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#include <linux/ptrace.h>
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#include <uapi/linux/bpf.h>
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#include <bpf/bpf_helpers.h>
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#define MAX_ENTRIES 20
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#define MAX_CPU 4
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/* We need to stick to static allocated memory (an array instead of
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* hash table) because managing dynamic memory from the
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* trace_preempt_[on|off] tracepoints hooks is not supported.
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*/
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struct bpf_map_def SEC("maps") my_map = {
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.type = BPF_MAP_TYPE_ARRAY,
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.key_size = sizeof(int),
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.value_size = sizeof(u64),
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.max_entries = MAX_CPU,
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};
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SEC("kprobe/trace_preempt_off")
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int bpf_prog1(struct pt_regs *ctx)
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{
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int cpu = bpf_get_smp_processor_id();
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u64 *ts = bpf_map_lookup_elem(&my_map, &cpu);
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if (ts)
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*ts = bpf_ktime_get_ns();
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return 0;
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}
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static unsigned int log2(unsigned int v)
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{
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unsigned int r;
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unsigned int shift;
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r = (v > 0xFFFF) << 4; v >>= r;
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shift = (v > 0xFF) << 3; v >>= shift; r |= shift;
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shift = (v > 0xF) << 2; v >>= shift; r |= shift;
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shift = (v > 0x3) << 1; v >>= shift; r |= shift;
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r |= (v >> 1);
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return r;
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}
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static unsigned int log2l(unsigned long v)
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{
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unsigned int hi = v >> 32;
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if (hi)
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return log2(hi) + 32;
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else
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return log2(v);
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}
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struct bpf_map_def SEC("maps") my_lat = {
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.type = BPF_MAP_TYPE_ARRAY,
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.key_size = sizeof(int),
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.value_size = sizeof(long),
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.max_entries = MAX_CPU * MAX_ENTRIES,
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};
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SEC("kprobe/trace_preempt_on")
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int bpf_prog2(struct pt_regs *ctx)
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{
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u64 *ts, cur_ts, delta;
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int key, cpu;
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long *val;
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cpu = bpf_get_smp_processor_id();
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ts = bpf_map_lookup_elem(&my_map, &cpu);
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if (!ts)
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return 0;
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cur_ts = bpf_ktime_get_ns();
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delta = log2l(cur_ts - *ts);
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if (delta > MAX_ENTRIES - 1)
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delta = MAX_ENTRIES - 1;
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key = cpu * MAX_ENTRIES + delta;
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val = bpf_map_lookup_elem(&my_lat, &key);
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if (val)
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__sync_fetch_and_add((long *)val, 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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