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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2021 Facebook */
#include <linux/bpf.h>
#include <time.h>
#include <errno.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
char _license[] SEC("license") = "GPL";
struct hmap_elem {
int pad; /* unused */
struct bpf_timer timer;
};
struct inner_map {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, 1024);
__type(key, int);
__type(value, struct hmap_elem);
} inner_htab SEC(".maps");
#define ARRAY_KEY 1
#define HASH_KEY 1234
struct outer_arr {
__uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS);
__uint(max_entries, 2);
__uint(key_size, sizeof(int));
__uint(value_size, sizeof(int));
__array(values, struct inner_map);
} outer_arr SEC(".maps") = {
.values = { [ARRAY_KEY] = &inner_htab },
};
__u64 err;
__u64 ok;
__u64 cnt;
static int timer_cb1(void *map, int *key, struct hmap_elem *val);
static int timer_cb2(void *map, int *key, struct hmap_elem *val)
{
cnt++;
bpf_timer_set_callback(&val->timer, timer_cb1);
if (bpf_timer_start(&val->timer, 1000, 0))
err |= 1;
ok |= 1;
return 0;
}
/* callback for inner hash map */
static int timer_cb1(void *map, int *key, struct hmap_elem *val)
{
cnt++;
bpf_timer_set_callback(&val->timer, timer_cb2);
if (bpf_timer_start(&val->timer, 1000, 0))
err |= 2;
/* Do a lookup to make sure 'map' and 'key' pointers are correct */
bpf_map_lookup_elem(map, key);
ok |= 2;
return 0;
}
SEC("fentry/bpf_fentry_test1")
int BPF_PROG(test1, int a)
{
struct hmap_elem init = {};
struct bpf_map *inner_map;
struct hmap_elem *val;
int array_key = ARRAY_KEY;
int hash_key = HASH_KEY;
inner_map = bpf_map_lookup_elem(&outer_arr, &array_key);
if (!inner_map)
return 0;
bpf_map_update_elem(inner_map, &hash_key, &init, 0);
val = bpf_map_lookup_elem(inner_map, &hash_key);
if (!val)
return 0;
bpf_timer_init(&val->timer, inner_map, CLOCK_MONOTONIC);
if (bpf_timer_set_callback(&val->timer, timer_cb1))
err |= 4;
if (bpf_timer_start(&val->timer, 0, 0))
err |= 8;
return 0;
}
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