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1// SPDX-License-Identifier: GPL-2.02// Copyright (c) 2020 Facebook3 4#include <linux/bpf.h>5#include <stdint.h>6#include <bpf/bpf_helpers.h>7#include "bpf_misc.h"8 9char _license[] SEC("license") = "GPL";10 11struct {12 __uint(type, BPF_MAP_TYPE_RINGBUF);13} ringbuf SEC(".maps");14 15const volatile int batch_cnt = 0;16const volatile long use_output = 0;17 18long sample_val = 42;19long dropped __attribute__((aligned(128))) = 0;20 21const volatile long wakeup_data_size = 0;22 23static __always_inline long get_flags()24{25 long sz;26 27 if (!wakeup_data_size)28 return 0;29 30 sz = bpf_ringbuf_query(&ringbuf, BPF_RB_AVAIL_DATA);31 return sz >= wakeup_data_size ? BPF_RB_FORCE_WAKEUP : BPF_RB_NO_WAKEUP;32}33 34SEC("fentry/" SYS_PREFIX "sys_getpgid")35int bench_ringbuf(void *ctx)36{37 long *sample, flags;38 int i;39 40 if (!use_output) {41 for (i = 0; i < batch_cnt; i++) {42 sample = bpf_ringbuf_reserve(&ringbuf,43 sizeof(sample_val), 0);44 if (!sample) {45 __sync_add_and_fetch(&dropped, 1);46 } else {47 *sample = sample_val;48 flags = get_flags();49 bpf_ringbuf_submit(sample, flags);50 }51 }52 } else {53 for (i = 0; i < batch_cnt; i++) {54 flags = get_flags();55 if (bpf_ringbuf_output(&ringbuf, &sample_val,56 sizeof(sample_val), flags))57 __sync_add_and_fetch(&dropped, 1);58 }59 }60 return 0;61}62