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// SPDX-License-Identifier: GPL-2.0
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
struct S {
int v;
};
struct S global_variable = {};
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 7);
__type(key, __u32);
__type(value, int);
} values SEC(".maps");
static void save_value(__u32 index, int value)
{
bpf_map_update_elem(&values, &index, &value, 0);
}
__noinline int foo(__u32 index, struct S *s)
{
if (s) {
save_value(index, s->v);
return ++s->v;
}
save_value(index, 0);
return 1;
}
__noinline int bar(__u32 index, volatile struct S *s)
{
if (s) {
save_value(index, s->v);
return ++s->v;
}
save_value(index, 0);
return 1;
}
__noinline int baz(struct S **s)
{
if (s)
*s = 0;
return 0;
}
SEC("cgroup_skb/ingress")
int test_cls(struct __sk_buff *skb)
{
__u32 index = 0;
{
const int v = foo(index++, 0);
save_value(index++, v);
}
{
struct S s = { .v = 100 };
foo(index++, &s);
save_value(index++, s.v);
}
{
global_variable.v = 42;
bar(index++, &global_variable);
save_value(index++, global_variable.v);
}
{
struct S v, *p = &v;
baz(&p);
save_value(index++, !p);
}
return 0;
}
char _license[] SEC("license") = "GPL";
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