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") bench_perfbuf(void * ctx)23int 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