1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2020 Facebook
3 
4 #include <linux/bpf.h>
5 #include <stdint.h>
6 #include <bpf/bpf_helpers.h>
7 #include "bpf_misc.h"
8 
9 char _license[] SEC("license") = "GPL";
10 
11 struct {
12 	__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
13 	__uint(value_size, sizeof(int));
14 	__uint(key_size, sizeof(int));
15 } perfbuf SEC(".maps");
16 
17 const volatile int batch_cnt = 0;
18 
19 long sample_val = 42;
20 long dropped __attribute__((aligned(128))) = 0;
21 
22 SEC("fentry/" SYS_PREFIX "sys_getpgid")
23 int bench_perfbuf(void *ctx)
24 {
25 	__u64 *sample;
26 	int i;
27 
28 	for (i = 0; i < batch_cnt; i++) {
29 		if (bpf_perf_event_output(ctx, &perfbuf, BPF_F_CURRENT_CPU,
30 					  &sample_val, sizeof(sample_val)))
31 			__sync_add_and_fetch(&dropped, 1);
32 	}
33 	return 0;
34 }
35