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 8 char _license[] SEC("license") = "GPL"; 9 10 struct { 11 __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY); 12 __uint(value_size, sizeof(int)); 13 __uint(key_size, sizeof(int)); 14 } perfbuf SEC(".maps"); 15 16 const volatile int batch_cnt = 0; 17 18 long sample_val = 42; 19 long dropped __attribute__((aligned(128))) = 0; 20 21 SEC("fentry/__x64_sys_getpgid") 22 int bench_perfbuf(void *ctx) 23 { 24 __u64 *sample; 25 int i; 26 27 for (i = 0; i < batch_cnt; i++) { 28 if (bpf_perf_event_output(ctx, &perfbuf, BPF_F_CURRENT_CPU, 29 &sample_val, sizeof(sample_val))) 30 __sync_add_and_fetch(&dropped, 1); 31 } 32 return 0; 33 } 34