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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2021 Facebook */
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
char _license[] SEC("license") = "GPL";
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 3);
__type(key, __u32);
__type(value, __u64);
} arraymap SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
__uint(max_entries, 1);
__type(key, __u32);
__type(value, __u64);
} percpu_map SEC(".maps");
struct callback_ctx {
int output;
};
const volatile int bypass_unused = 1;
static __u64
unused_subprog(struct bpf_map *map, __u32 *key, __u64 *val,
struct callback_ctx *data)
{
data->output = 0;
return 1;
}
static __u64
check_array_elem(struct bpf_map *map, __u32 *key, __u64 *val,
struct callback_ctx *data)
{
data->output += *val;
if (*key == 1)
return 1; /* stop the iteration */
return 0;
}
__u32 cpu = 0;
__u64 percpu_val = 0;
static __u64
check_percpu_elem(struct bpf_map *map, __u32 *key, __u64 *val,
struct callback_ctx *data)
{
cpu = bpf_get_smp_processor_id();
percpu_val = *val;
return 0;
}
u32 arraymap_output = 0;
SEC("tc")
int test_pkt_access(struct __sk_buff *skb)
{
struct callback_ctx data;
data.output = 0;
bpf_for_each_map_elem(&arraymap, check_array_elem, &data, 0);
if (!bypass_unused)
bpf_for_each_map_elem(&arraymap, unused_subprog, &data, 0);
arraymap_output = data.output;
bpf_for_each_map_elem(&percpu_map, check_percpu_elem, (void *)0, 0);
return 0;
}
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