crates/libbpf-rs/tests/bin/src/usdt.bpf.c

// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2021 William Findlay
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
#include <bpf/usdt.bpf.h>

struct {
    __uint(type, BPF_MAP_TYPE_RINGBUF);
    __uint(max_entries, 4096 /* one page */);
} ringbuf SEC(".maps");

SEC("usdt")
int handle__usdt(void *ctx)
{
    int *value;

    value = bpf_ringbuf_reserve(&ringbuf, sizeof(int), 0);
    if (!value) {
        bpf_printk("handle__usdt: failed to reserve ring buffer space");
        return 1;
    }

    *value = 1;
    bpf_ringbuf_submit(value, 0);
    bpf_printk("handle__usdt: submitted ringbuf value");
    return 0;
}

SEC("usdt")
int handle__usdt_with_cookie(void *ctx)
{
    int *value;

    value = bpf_ringbuf_reserve(&ringbuf, sizeof(int), 0);
    if (!value) {
        bpf_printk("handle__usdt_with_cookie: failed to reserve ring buffer space");
        return 1;
    }

    *value = bpf_usdt_cookie(ctx);
    bpf_printk("handle__usdt_with_cookie: cookie=%d", *value);
    bpf_ringbuf_submit(value, 0);
    return 0;
}

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