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