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1// SPDX-License-Identifier: GPL-2.02/* Copyright (c) 2022 Google */3 4#include "bpf_iter.h"5#include <bpf/bpf_helpers.h>6#include <bpf/bpf_tracing.h>7 8char _license[] SEC("license") = "GPL";9int terminate_early = 0;10u64 terminal_cgroup = 0;11 12static inline u64 cgroup_id(struct cgroup *cgrp)13{14 return cgrp->kn->id;15}16 17SEC("iter/cgroup")18int cgroup_id_printer(struct bpf_iter__cgroup *ctx)19{20 struct seq_file *seq = ctx->meta->seq;21 struct cgroup *cgrp = ctx->cgroup;22 23 /* epilogue */24 if (cgrp == NULL) {25 BPF_SEQ_PRINTF(seq, "epilogue\n");26 return 0;27 }28 29 /* prologue */30 if (ctx->meta->seq_num == 0)31 BPF_SEQ_PRINTF(seq, "prologue\n");32 33 BPF_SEQ_PRINTF(seq, "%8llu\n", cgroup_id(cgrp));34 35 if (terminal_cgroup == cgroup_id(cgrp))36 return 1;37 38 return terminate_early ? 1 : 0;39}40