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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 8struct my_key { long x; };9struct my_value { long x; };10 11struct {12 __uint(type, BPF_MAP_TYPE_HASH);13 __type(key, struct my_key);14 __type(value, struct my_value);15 __uint(max_entries, 16);16} map1 SEC(".maps");17 18 /* Matches map2 definition in linked_maps2.c. Order of the attributes doesn't19 * matter.20 */21typedef struct {22 __uint(max_entries, 8);23 __type(key, int);24 __type(value, int);25 __uint(type, BPF_MAP_TYPE_ARRAY);26} map2_t;27 28extern map2_t map2 SEC(".maps");29 30/* This should be the winning map definition, but we have no way of verifying,31 * so we just make sure that it links and works without errors32 */33struct {34 __uint(type, BPF_MAP_TYPE_ARRAY);35 __type(key, int);36 __type(value, int);37 __uint(max_entries, 16);38} map_weak __weak SEC(".maps");39 40int output_first1;41int output_second1;42int output_weak1;43 44SEC("raw_tp/sys_enter")45int BPF_PROG(handler_enter1)46{47 /* update values with key = 1 */48 int key = 1, val = 1;49 struct my_key key_struct = { .x = 1 };50 struct my_value val_struct = { .x = 1000 };51 52 bpf_map_update_elem(&map1, &key_struct, &val_struct, 0);53 bpf_map_update_elem(&map2, &key, &val, 0);54 bpf_map_update_elem(&map_weak, &key, &val, 0);55 56 return 0;57}58 59SEC("raw_tp/sys_exit")60int BPF_PROG(handler_exit1)61{62 /* lookup values with key = 2, set in another file */63 int key = 2, *val;64 struct my_key key_struct = { .x = 2 };65 struct my_value *value_struct;66 67 value_struct = bpf_map_lookup_elem(&map1, &key_struct);68 if (value_struct)69 output_first1 = value_struct->x;70 71 val = bpf_map_lookup_elem(&map2, &key);72 if (val)73 output_second1 = *val;74 75 val = bpf_map_lookup_elem(&map_weak, &key);76 if (val)77 output_weak1 = *val;78 79 return 0;80}81 82char LICENSE[] SEC("license") = "GPL";83