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

// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Facebook */
#include "bpf_iter.h"
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>

char _license[] SEC("license") = "GPL";

SEC("iter/task")
int dump_task(struct bpf_iter__task *ctx)
{
	struct seq_file *seq = ctx->meta->seq;
	struct task_struct *task = ctx->task;
	static char info[] = "    === END ===";

	if (task == (void *)0) {
		BPF_SEQ_PRINTF(seq, "%s\n", info);
		return 0;
	}

	if (ctx->meta->seq_num == 0)
		BPF_SEQ_PRINTF(seq, "    tgid      gid\n");

	BPF_SEQ_PRINTF(seq, "%8d %8d\n", task->tgid, task->pid);
	return 0;
}