102 lines
2.1 KiB
C
102 lines
2.1 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
// Copyright (c) 2019 Facebook
|
|
#include <linux/bpf.h>
|
|
#include <linux/version.h>
|
|
#include <bpf/bpf_helpers.h>
|
|
|
|
struct hmap_elem {
|
|
volatile int cnt;
|
|
struct bpf_spin_lock lock;
|
|
int test_padding;
|
|
};
|
|
|
|
struct {
|
|
__uint(type, BPF_MAP_TYPE_HASH);
|
|
__uint(max_entries, 1);
|
|
__type(key, int);
|
|
__type(value, struct hmap_elem);
|
|
} hmap SEC(".maps");
|
|
|
|
struct cls_elem {
|
|
struct bpf_spin_lock lock;
|
|
volatile int cnt;
|
|
};
|
|
|
|
struct {
|
|
__uint(type, BPF_MAP_TYPE_CGROUP_STORAGE);
|
|
__type(key, struct bpf_cgroup_storage_key);
|
|
__type(value, struct cls_elem);
|
|
} cls_map SEC(".maps");
|
|
|
|
struct bpf_vqueue {
|
|
struct bpf_spin_lock lock;
|
|
/* 4 byte hole */
|
|
unsigned long long lasttime;
|
|
int credit;
|
|
unsigned int rate;
|
|
};
|
|
|
|
struct {
|
|
__uint(type, BPF_MAP_TYPE_ARRAY);
|
|
__uint(max_entries, 1);
|
|
__type(key, int);
|
|
__type(value, struct bpf_vqueue);
|
|
} vqueue SEC(".maps");
|
|
|
|
#define CREDIT_PER_NS(delta, rate) (((delta) * rate) >> 20)
|
|
|
|
SEC("cgroup_skb/ingress")
|
|
int bpf_spin_lock_test(struct __sk_buff *skb)
|
|
{
|
|
volatile int credit = 0, max_credit = 100, pkt_len = 64;
|
|
struct hmap_elem zero = {}, *val;
|
|
unsigned long long curtime;
|
|
struct bpf_vqueue *q;
|
|
struct cls_elem *cls;
|
|
int key = 0;
|
|
int err = 0;
|
|
|
|
val = bpf_map_lookup_elem(&hmap, &key);
|
|
if (!val) {
|
|
bpf_map_update_elem(&hmap, &key, &zero, 0);
|
|
val = bpf_map_lookup_elem(&hmap, &key);
|
|
if (!val) {
|
|
err = 1;
|
|
goto err;
|
|
}
|
|
}
|
|
/* spin_lock in hash map run time test */
|
|
bpf_spin_lock(&val->lock);
|
|
if (val->cnt)
|
|
val->cnt--;
|
|
else
|
|
val->cnt++;
|
|
if (val->cnt != 0 && val->cnt != 1)
|
|
err = 1;
|
|
bpf_spin_unlock(&val->lock);
|
|
|
|
/* spin_lock in array. virtual queue demo */
|
|
q = bpf_map_lookup_elem(&vqueue, &key);
|
|
if (!q)
|
|
goto err;
|
|
curtime = bpf_ktime_get_ns();
|
|
bpf_spin_lock(&q->lock);
|
|
q->credit += CREDIT_PER_NS(curtime - q->lasttime, q->rate);
|
|
q->lasttime = curtime;
|
|
if (q->credit > max_credit)
|
|
q->credit = max_credit;
|
|
q->credit -= pkt_len;
|
|
credit = q->credit;
|
|
bpf_spin_unlock(&q->lock);
|
|
|
|
/* spin_lock in cgroup local storage */
|
|
cls = bpf_get_local_storage(&cls_map, 0);
|
|
bpf_spin_lock(&cls->lock);
|
|
cls->cnt++;
|
|
bpf_spin_unlock(&cls->lock);
|
|
|
|
err:
|
|
return err;
|
|
}
|
|
char _license[] SEC("license") = "GPL";
|