1// SPDX-License-Identifier: GPL-2.0
  2// Copyright (c) 2019 Facebook
  3#include <linux/bpf.h>
  4#include <linux/version.h>
  5#include "bpf_helpers.h"
  6
  7struct hmap_elem {
  8	volatile int cnt;
  9	struct bpf_spin_lock lock;
 10	int test_padding;
 11};
 12
 13struct {
 14	__uint(type, BPF_MAP_TYPE_HASH);
 15	__uint(max_entries, 1);
 16	__type(key, int);
 17	__type(value, struct hmap_elem);
 18} hmap SEC(".maps");
 19
 20struct cls_elem {
 21	struct bpf_spin_lock lock;
 22	volatile int cnt;
 23};
 24
 25struct {
 26	__uint(type, BPF_MAP_TYPE_CGROUP_STORAGE);
 27	__type(key, struct bpf_cgroup_storage_key);
 28	__type(value, struct cls_elem);
 29} cls_map SEC(".maps");
 30
 31struct bpf_vqueue {
 32	struct bpf_spin_lock lock;
 33	/* 4 byte hole */
 34	unsigned long long lasttime;
 35	int credit;
 36	unsigned int rate;
 37};
 38
 39struct {
 40	__uint(type, BPF_MAP_TYPE_ARRAY);
 41	__uint(max_entries, 1);
 42	__type(key, int);
 43	__type(value, struct bpf_vqueue);
 44} vqueue SEC(".maps");
 45
 46#define CREDIT_PER_NS(delta, rate) (((delta) * rate) >> 20)
 47
 48SEC("spin_lock_demo")
 49int bpf_sping_lock_test(struct __sk_buff *skb)
 50{
 51	volatile int credit = 0, max_credit = 100, pkt_len = 64;
 52	struct hmap_elem zero = {}, *val;
 53	unsigned long long curtime;
 54	struct bpf_vqueue *q;
 55	struct cls_elem *cls;
 56	int key = 0;
 57	int err = 0;
 58
 59	val = bpf_map_lookup_elem(&hmap, &key);
 60	if (!val) {
 61		bpf_map_update_elem(&hmap, &key, &zero, 0);
 62		val = bpf_map_lookup_elem(&hmap, &key);
 63		if (!val) {
 64			err = 1;
 65			goto err;
 66		}
 67	}
 68	/* spin_lock in hash map run time test */
 69	bpf_spin_lock(&val->lock);
 70	if (val->cnt)
 71		val->cnt--;
 72	else
 73		val->cnt++;
 74	if (val->cnt != 0 && val->cnt != 1)
 75		err = 1;
 76	bpf_spin_unlock(&val->lock);
 77
 78	/* spin_lock in array. virtual queue demo */
 79	q = bpf_map_lookup_elem(&vqueue, &key);
 80	if (!q)
 81		goto err;
 82	curtime = bpf_ktime_get_ns();
 83	bpf_spin_lock(&q->lock);
 84	q->credit += CREDIT_PER_NS(curtime - q->lasttime, q->rate);
 85	q->lasttime = curtime;
 86	if (q->credit > max_credit)
 87		q->credit = max_credit;
 88	q->credit -= pkt_len;
 89	credit = q->credit;
 90	bpf_spin_unlock(&q->lock);
 91
 92	/* spin_lock in cgroup local storage */
 93	cls = bpf_get_local_storage(&cls_map, 0);
 94	bpf_spin_lock(&cls->lock);
 95	cls->cnt++;
 96	bpf_spin_unlock(&cls->lock);
 97
 98err:
 99	return err;
100}
101char _license[] SEC("license") = "GPL";

  1// SPDX-License-Identifier: GPL-2.0
  2// Copyright (c) 2019 Facebook
  3#include <linux/bpf.h>
  4#include <linux/version.h>
  5#include <bpf/bpf_helpers.h>
  6
  7struct hmap_elem {
  8	volatile int cnt;
  9	struct bpf_spin_lock lock;
 10	int test_padding;
 11};
 12
 13struct {
 14	__uint(type, BPF_MAP_TYPE_HASH);
 15	__uint(max_entries, 1);
 16	__type(key, int);
 17	__type(value, struct hmap_elem);
 18} hmap SEC(".maps");
 19
 20struct cls_elem {
 21	struct bpf_spin_lock lock;
 22	volatile int cnt;
 23};
 24
 25struct {
 26	__uint(type, BPF_MAP_TYPE_CGROUP_STORAGE);
 27	__type(key, struct bpf_cgroup_storage_key);
 28	__type(value, struct cls_elem);
 29} cls_map SEC(".maps");
 30
 31struct bpf_vqueue {
 32	struct bpf_spin_lock lock;
 33	/* 4 byte hole */
 34	unsigned long long lasttime;
 35	int credit;
 36	unsigned int rate;
 37};
 38
 39struct {
 40	__uint(type, BPF_MAP_TYPE_ARRAY);
 41	__uint(max_entries, 1);
 42	__type(key, int);
 43	__type(value, struct bpf_vqueue);
 44} vqueue SEC(".maps");
 45
 46#define CREDIT_PER_NS(delta, rate) (((delta) * rate) >> 20)
 47
 48SEC("cgroup_skb/ingress")
 49int bpf_spin_lock_test(struct __sk_buff *skb)
 50{
 51	volatile int credit = 0, max_credit = 100, pkt_len = 64;
 52	struct hmap_elem zero = {}, *val;
 53	unsigned long long curtime;
 54	struct bpf_vqueue *q;
 55	struct cls_elem *cls;
 56	int key = 0;
 57	int err = 0;
 58
 59	val = bpf_map_lookup_elem(&hmap, &key);
 60	if (!val) {
 61		bpf_map_update_elem(&hmap, &key, &zero, 0);
 62		val = bpf_map_lookup_elem(&hmap, &key);
 63		if (!val) {
 64			err = 1;
 65			goto err;
 66		}
 67	}
 68	/* spin_lock in hash map run time test */
 69	bpf_spin_lock(&val->lock);
 70	if (val->cnt)
 71		val->cnt--;
 72	else
 73		val->cnt++;
 74	if (val->cnt != 0 && val->cnt != 1)
 75		err = 1;
 76	bpf_spin_unlock(&val->lock);
 77
 78	/* spin_lock in array. virtual queue demo */
 79	q = bpf_map_lookup_elem(&vqueue, &key);
 80	if (!q)
 81		goto err;
 82	curtime = bpf_ktime_get_ns();
 83	bpf_spin_lock(&q->lock);
 84	q->credit += CREDIT_PER_NS(curtime - q->lasttime, q->rate);
 85	q->lasttime = curtime;
 86	if (q->credit > max_credit)
 87		q->credit = max_credit;
 88	q->credit -= pkt_len;
 89	credit = q->credit;
 90	bpf_spin_unlock(&q->lock);
 91
 92	/* spin_lock in cgroup local storage */
 93	cls = bpf_get_local_storage(&cls_map, 0);
 94	bpf_spin_lock(&cls->lock);
 95	cls->cnt++;
 96	bpf_spin_unlock(&cls->lock);
 97
 98err:
 99	return err;
100}
101char _license[] SEC("license") = "GPL";