1 files changed, 108 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_spin_lock.c b/tools/testing/selftests/bpf/progs/test_spin_lock.c
new file mode 100644
index 000000000000..40f904312090
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_spin_lock.c
@@ -0,0 +1,108 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2019 Facebook
+#include <linux/bpf.h>
+#include <linux/version.h>
+#include "bpf_helpers.h"
+
+struct hmap_elem {
+	volatile int cnt;
+	struct bpf_spin_lock lock;
+	int test_padding;
+};
+
+struct bpf_map_def SEC("maps") hmap = {
+	.type = BPF_MAP_TYPE_HASH,
+	.key_size = sizeof(int),
+	.value_size = sizeof(struct hmap_elem),
+	.max_entries = 1,
+};
+
+BPF_ANNOTATE_KV_PAIR(hmap, int, struct hmap_elem);
+
+
+struct cls_elem {
+	struct bpf_spin_lock lock;
+	volatile int cnt;
+};
+
+struct bpf_map_def SEC("maps") cls_map = {
+	.type = BPF_MAP_TYPE_CGROUP_STORAGE,
+	.key_size = sizeof(struct bpf_cgroup_storage_key),
+	.value_size = sizeof(struct cls_elem),
+};
+
+BPF_ANNOTATE_KV_PAIR(cls_map, struct bpf_cgroup_storage_key,
+		     struct cls_elem);
+
+struct bpf_vqueue {
+	struct bpf_spin_lock lock;
+	/* 4 byte hole */
+	unsigned long long lasttime;
+	int credit;
+	unsigned int rate;
+};
+
+struct bpf_map_def SEC("maps") vqueue = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(int),
+	.value_size = sizeof(struct bpf_vqueue),
+	.max_entries = 1,
+};
+
+BPF_ANNOTATE_KV_PAIR(vqueue, int, struct bpf_vqueue);
+#define CREDIT_PER_NS(delta, rate) (((delta) * rate) >> 20)
+
+SEC("spin_lock_demo")
+int bpf_sping_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";