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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_HASH);
__uint(max_entries, 3);
__type(key, __u32);
__type(value, __u64);
} hashmap SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_PERCPU_HASH);
__uint(max_entries, 1);
__type(key, __u32);
__type(value, __u64);
} percpu_map SEC(".maps");
struct callback_ctx {
struct __sk_buff *ctx;
int input;
int output;
};
static __u64
check_hash_elem(struct bpf_map *map, __u32 *key, __u64 *val,
struct callback_ctx *data)
{
struct __sk_buff *skb = data->ctx;
__u32 k;
__u64 v;
if (skb) {
k = *key;
v = *val;
if (skb->len == 10000 && k == 10 && v == 10)
data->output = 3; /* impossible path */
else
data->output = 4;
} else {
data->output = data->input;
bpf_map_delete_elem(map, key);
}
return 0;
}
__u32 cpu = 0;
__u32 percpu_called = 0;
__u32 percpu_key = 0;
__u64 percpu_val = 0;
int percpu_output = 0;
static __u64
check_percpu_elem(struct bpf_map *map, __u32 *key, __u64 *val,
struct callback_ctx *unused)
{
struct callback_ctx data;
percpu_called++;
cpu = bpf_get_smp_processor_id();
percpu_key = *key;
percpu_val = *val;
data.ctx = 0;
data.input = 100;
data.output = 0;
bpf_for_each_map_elem(&hashmap, check_hash_elem, &data, 0);
percpu_output = data.output;
return 0;
}
int hashmap_output = 0;
int hashmap_elems = 0;
int percpu_map_elems = 0;
SEC("tc")
int test_pkt_access(struct __sk_buff *skb)
{
struct callback_ctx data;
data.ctx = skb;
data.input = 10;
data.output = 0;
hashmap_elems = bpf_for_each_map_elem(&hashmap, check_hash_elem, &data, 0);
hashmap_output = data.output;
percpu_map_elems = bpf_for_each_map_elem(&percpu_map, check_percpu_elem,
(void *)0, 0);
return 0;
}
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