77 lines
1.7 KiB
C
77 lines
1.7 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2021 Facebook */
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#include "vmlinux.h"
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_tracing.h>
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/* modifiers and typedefs are ignored when comparing key/value types */
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typedef struct my_key { long x; } key_type;
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typedef struct my_value { long x; } value_type;
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extern struct {
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__uint(max_entries, 16);
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__type(key, key_type);
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__type(value, value_type);
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__uint(type, BPF_MAP_TYPE_HASH);
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} map1 SEC(".maps");
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struct {
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__uint(type, BPF_MAP_TYPE_ARRAY);
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__type(key, int);
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__type(value, int);
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__uint(max_entries, 8);
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} map2 SEC(".maps");
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/* this definition will lose, but it has to exactly match the winner */
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struct {
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__uint(type, BPF_MAP_TYPE_ARRAY);
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__type(key, int);
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__type(value, int);
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__uint(max_entries, 16);
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} map_weak __weak SEC(".maps");
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int output_first2;
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int output_second2;
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int output_weak2;
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SEC("raw_tp/sys_enter")
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int BPF_PROG(handler_enter2)
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{
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/* update values with key = 2 */
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int key = 2, val = 2;
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key_type key_struct = { .x = 2 };
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value_type val_struct = { .x = 2000 };
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bpf_map_update_elem(&map1, &key_struct, &val_struct, 0);
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bpf_map_update_elem(&map2, &key, &val, 0);
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bpf_map_update_elem(&map_weak, &key, &val, 0);
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return 0;
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}
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SEC("raw_tp/sys_exit")
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int BPF_PROG(handler_exit2)
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{
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/* lookup values with key = 1, set in another file */
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int key = 1, *val;
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key_type key_struct = { .x = 1 };
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value_type *value_struct;
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value_struct = bpf_map_lookup_elem(&map1, &key_struct);
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if (value_struct)
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output_first2 = value_struct->x;
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val = bpf_map_lookup_elem(&map2, &key);
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if (val)
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output_second2 = *val;
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val = bpf_map_lookup_elem(&map_weak, &key);
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if (val)
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output_weak2 = *val;
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return 0;
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}
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char LICENSE[] SEC("license") = "GPL";
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