1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2020 Facebook
3
4 #include <stdbool.h>
5 #include <linux/bpf.h>
6 #include <stdint.h>
7 #include <bpf/bpf_helpers.h>
8 #include "bpf_misc.h"
9
10 char _license[] SEC("license") = "GPL";
11
12 struct {
13 __uint(type, BPF_MAP_TYPE_RINGBUF);
14 } ringbuf SEC(".maps");
15
16 const volatile int batch_cnt = 0;
17 const volatile long use_output = 0;
18 const volatile bool bench_producer = false;
19
20 long sample_val = 42;
21 long dropped __attribute__((aligned(128))) = 0;
22 long hits __attribute__((aligned(128))) = 0;
23
24 const volatile long wakeup_data_size = 0;
25
get_flags()26 static __always_inline long get_flags()
27 {
28 long sz;
29
30 if (bench_producer)
31 return BPF_RB_NO_WAKEUP;
32
33 if (!wakeup_data_size)
34 return 0;
35
36 sz = bpf_ringbuf_query(&ringbuf, BPF_RB_AVAIL_DATA);
37 return sz >= wakeup_data_size ? BPF_RB_FORCE_WAKEUP : BPF_RB_NO_WAKEUP;
38 }
39
40 SEC("fentry/" SYS_PREFIX "sys_getpgid")
bench_ringbuf(void * ctx)41 int bench_ringbuf(void *ctx)
42 {
43 long *sample, flags;
44 int i;
45
46 if (!use_output) {
47 for (i = 0; i < batch_cnt; i++) {
48 sample = bpf_ringbuf_reserve(&ringbuf,
49 sizeof(sample_val), 0);
50 if (!sample) {
51 __sync_add_and_fetch(&dropped, 1);
52 } else {
53 *sample = sample_val;
54 flags = get_flags();
55 bpf_ringbuf_submit(sample, flags);
56 if (bench_producer)
57 __sync_add_and_fetch(&hits, 1);
58 }
59 }
60 } else {
61 for (i = 0; i < batch_cnt; i++) {
62 flags = get_flags();
63 if (bpf_ringbuf_output(&ringbuf, &sample_val,
64 sizeof(sample_val), flags))
65 __sync_add_and_fetch(&dropped, 1);
66 else if (bench_producer)
67 __sync_add_and_fetch(&hits, 1);
68
69 }
70 }
71 return 0;
72 }
73