1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c) 2020, Oracle and/or its affiliates. */
3#include "bpf_iter.h"
4#include <bpf/bpf_helpers.h>
5#include <bpf/bpf_core_read.h>
6
7#include <errno.h>
8
9char _license[] SEC("license") = "GPL";
10
11long tasks = 0;
12long seq_err = 0;
13bool skip = false;
14
15SEC("iter/task")
16int dump_task_struct(struct bpf_iter__task *ctx)
17{
18	struct seq_file *seq = ctx->meta->seq;
19	struct task_struct *task = ctx->task;
20	static struct btf_ptr ptr = { };
21	long ret;
22
23#if __has_builtin(__builtin_btf_type_id)
24	ptr.type_id = bpf_core_type_id_kernel(struct task_struct);
25	ptr.ptr = task;
26
27	if (ctx->meta->seq_num == 0)
28		BPF_SEQ_PRINTF(seq, "Raw BTF task\n");
29
30	ret = bpf_seq_printf_btf(seq, &ptr, sizeof(ptr), 0);
31	switch (ret) {
32	case 0:
33		tasks++;
34		break;
35	case -ERANGE:
36		/* NULL task or task->fs, don't count it as an error. */
37		break;
38	case -E2BIG:
39		return 1;
40	default:
41		seq_err = ret;
42		break;
43	}
44#else
45	skip = true;
46#endif
47
48	return 0;
49}
50