linuxdebug/tools/testing/selftests/bpf/progs/ringbuf_bench.c

62 lines
1.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2020 Facebook
#include <linux/bpf.h>
#include <stdint.h>
#include <bpf/bpf_helpers.h>
#include "bpf_misc.h"
char _license[] SEC("license") = "GPL";
struct {
__uint(type, BPF_MAP_TYPE_RINGBUF);
} ringbuf SEC(".maps");
const volatile int batch_cnt = 0;
const volatile long use_output = 0;
long sample_val = 42;
long dropped __attribute__((aligned(128))) = 0;
const volatile long wakeup_data_size = 0;
static __always_inline long get_flags()
{
long sz;
if (!wakeup_data_size)
return 0;
sz = bpf_ringbuf_query(&ringbuf, BPF_RB_AVAIL_DATA);
return sz >= wakeup_data_size ? BPF_RB_FORCE_WAKEUP : BPF_RB_NO_WAKEUP;
}
SEC("fentry/" SYS_PREFIX "sys_getpgid")
int bench_ringbuf(void *ctx)
{
long *sample, flags;
int i;
if (!use_output) {
for (i = 0; i < batch_cnt; i++) {
sample = bpf_ringbuf_reserve(&ringbuf,
sizeof(sample_val), 0);
if (!sample) {
__sync_add_and_fetch(&dropped, 1);
} else {
*sample = sample_val;
flags = get_flags();
bpf_ringbuf_submit(sample, flags);
}
}
} else {
for (i = 0; i < batch_cnt; i++) {
flags = get_flags();
if (bpf_ringbuf_output(&ringbuf, &sample_val,
sizeof(sample_val), flags))
__sync_add_and_fetch(&dropped, 1);
}
}
return 0;
}