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1// SPDX-License-Identifier: GPL-2.02// Copyright (c) 2024 Andrea Righi <andrea.righi@canonical.com>3 4#include <linux/bpf.h>5#include <sched.h>6#include <unistd.h>7#include <bpf/bpf_helpers.h>8#include "bpf_misc.h"9 10char _license[] SEC("license") = "GPL";11 12#define TASK_COMM_LEN 1613 14struct sample {15 int pid;16 long value;17 char comm[16];18};19 20struct {21 __uint(type, BPF_MAP_TYPE_RINGBUF);22} ringbuf SEC(".maps");23 24int pid = 0;25long value = 0;26 27SEC("fentry/" SYS_PREFIX "sys_getpgid")28int test_ringbuf_n(void *ctx)29{30 int cur_pid = bpf_get_current_pid_tgid() >> 32;31 struct sample *sample;32 33 if (cur_pid != pid)34 return 0;35 36 sample = bpf_ringbuf_reserve(&ringbuf, sizeof(*sample), 0);37 if (!sample)38 return 0;39 40 sample->pid = pid;41 sample->value = value;42 bpf_get_current_comm(sample->comm, sizeof(sample->comm));43 44 bpf_ringbuf_submit(sample, 0);45 46 return 0;47}48