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1// SPDX-License-Identifier: GPL-2.02/* Copyright (c) 2021 Facebook */3 4#include "vmlinux.h"5#include <bpf/bpf_helpers.h>6#include <bpf/bpf_tracing.h>7 8/* modifiers and typedefs are ignored when comparing key/value types */9typedef struct my_key { long x; } key_type;10typedef struct my_value { long x; } value_type;11 12extern struct {13 __uint(max_entries, 16);14 __type(key, key_type);15 __type(value, value_type);16 __uint(type, BPF_MAP_TYPE_HASH);17} map1 SEC(".maps");18 19struct {20 __uint(type, BPF_MAP_TYPE_ARRAY);21 __type(key, int);22 __type(value, int);23 __uint(max_entries, 8);24} map2 SEC(".maps");25 26/* this definition will lose, but it has to exactly match the winner */27struct {28 __uint(type, BPF_MAP_TYPE_ARRAY);29 __type(key, int);30 __type(value, int);31 __uint(max_entries, 16);32} map_weak __weak SEC(".maps");33 34int output_first2;35int output_second2;36int output_weak2;37 38SEC("raw_tp/sys_enter")39int BPF_PROG(handler_enter2)40{41 /* update values with key = 2 */42 int key = 2, val = 2;43 key_type key_struct = { .x = 2 };44 value_type val_struct = { .x = 2000 };45 46 bpf_map_update_elem(&map1, &key_struct, &val_struct, 0);47 bpf_map_update_elem(&map2, &key, &val, 0);48 bpf_map_update_elem(&map_weak, &key, &val, 0);49 50 return 0;51}52 53SEC("raw_tp/sys_exit")54int BPF_PROG(handler_exit2)55{56 /* lookup values with key = 1, set in another file */57 int key = 1, *val;58 key_type key_struct = { .x = 1 };59 value_type *value_struct;60 61 value_struct = bpf_map_lookup_elem(&map1, &key_struct);62 if (value_struct)63 output_first2 = value_struct->x;64 65 val = bpf_map_lookup_elem(&map2, &key);66 if (val)67 output_second2 = *val;68 69 val = bpf_map_lookup_elem(&map_weak, &key);70 if (val)71 output_weak2 = *val;72 73 return 0;74}75 76char LICENSE[] SEC("license") = "GPL";77