tools/testing/selftests/bpf/progs/bloom_filter_map.c

Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/progs/bloom_filter_map.c

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/bpf/progs/bloom_filter_map.c
Extension
.c
Size
1563 bytes
Lines
84
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

struct map_bloom_type {
	__uint(type, BPF_MAP_TYPE_BLOOM_FILTER);
	__type(value, __u32);
	__uint(max_entries, 10000);
	__uint(map_extra, 5);
} map_bloom SEC(".maps");

struct {
	__uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS);
	__type(key, int);
	__type(value, int);
	__uint(max_entries, 1);
	__array(values, struct map_bloom_type);
} outer_map SEC(".maps");

struct callback_ctx {
	struct bpf_map *map;
};

int error = 0;

static __u64
check_elem(struct bpf_map *map, __u32 *key, __u32 *val,
	   struct callback_ctx *data)
{
	int err;

	err = bpf_map_peek_elem(data->map, val);
	if (err) {
		error |= 1;
		return 1; /* stop the iteration */
	}

	return 0;
}

SEC("fentry/" SYS_PREFIX "sys_getpgid")
int inner_map(void *ctx)
{
	struct bpf_map *inner_map;
	struct callback_ctx data;
	int key = 0;

	inner_map = bpf_map_lookup_elem(&outer_map, &key);
	if (!inner_map) {
		error |= 2;
		return 0;
	}

	data.map = inner_map;
	bpf_for_each_map_elem(&map_random_data, check_elem, &data, 0);

	return 0;
}

SEC("fentry/" SYS_PREFIX "sys_getpgid")
int check_bloom(void *ctx)
{
	struct callback_ctx data;

	data.map = (struct bpf_map *)&map_bloom;
	bpf_for_each_map_elem(&map_random_data, check_elem, &data, 0);

	return 0;
}

Annotation

Implementation Notes