| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* Copyright (c) 2020 Facebook */ |
| /* "undefine" structs in vmlinux.h, because we "override" them below */ |
| #define bpf_iter_meta bpf_iter_meta___not_used |
| #define bpf_iter__task bpf_iter__task___not_used |
| #include "vmlinux.h" |
| #undef bpf_iter_meta |
| #undef bpf_iter__task |
| #include <bpf/bpf_helpers.h> |
| |
| char _license[] SEC("license") = "GPL"; |
| int count = 0; |
| |
| struct bpf_iter_meta { |
| struct seq_file *seq; |
| __u64 session_id; |
| __u64 seq_num; |
| } __attribute__((preserve_access_index)); |
| |
| struct bpf_iter__task { |
| struct bpf_iter_meta *meta; |
| struct task_struct *task; |
| } __attribute__((preserve_access_index)); |
| |
| SEC("iter/task") |
| int dump_task(struct bpf_iter__task *ctx) |
| { |
| struct seq_file *seq = ctx->meta->seq; |
| char c; |
| |
| if (count < 4) { |
| c = START_CHAR + count; |
| bpf_seq_write(seq, &c, sizeof(c)); |
| count++; |
| } |
| |
| return 0; |
| } |