1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * iteration_check_2.c: Check that deleting a tagged entry doesn't cause
4 * an RCU walker to finish early.
5 * Copyright (c) 2020 Oracle
6 * Author: Matthew Wilcox <willy@infradead.org>
7 */
8#include <pthread.h>
9#include "test.h"
10
11static volatile bool test_complete;
12
13static void *iterator(void *arg)
14{
15	XA_STATE(xas, arg, 0);
16	void *entry;
17
18	rcu_register_thread();
19
20	while (!test_complete) {
21		xas_set(&xas, 0);
22		rcu_read_lock();
23		xas_for_each_marked(&xas, entry, ULONG_MAX, XA_MARK_0)
24			;
25		rcu_read_unlock();
26		assert(xas.xa_index >= 100);
27	}
28
29	rcu_unregister_thread();
30	return NULL;
31}
32
33static void *throbber(void *arg)
34{
35	struct xarray *xa = arg;
36
37	rcu_register_thread();
38
39	while (!test_complete) {
40		int i;
41
42		for (i = 0; i < 100; i++) {
43			xa_store(xa, i, xa_mk_value(i), GFP_KERNEL);
44			xa_set_mark(xa, i, XA_MARK_0);
45		}
46		for (i = 0; i < 100; i++)
47			xa_erase(xa, i);
48	}
49
50	rcu_unregister_thread();
51	return NULL;
52}
53
54void iteration_test2(unsigned test_duration)
55{
56	pthread_t threads[2];
57	DEFINE_XARRAY(array);
58	int i;
59
60	printv(1, "Running iteration test 2 for %d seconds\n", test_duration);
61
62	test_complete = false;
63
64	xa_store(&array, 100, xa_mk_value(100), GFP_KERNEL);
65	xa_set_mark(&array, 100, XA_MARK_0);
66
67	if (pthread_create(&threads[0], NULL, iterator, &array)) {
68		perror("create iterator thread");
69		exit(1);
70	}
71	if (pthread_create(&threads[1], NULL, throbber, &array)) {
72		perror("create throbber thread");
73		exit(1);
74	}
75
76	sleep(test_duration);
77	test_complete = true;
78
79	for (i = 0; i < 2; i++) {
80		if (pthread_join(threads[i], NULL)) {
81			perror("pthread_join");
82			exit(1);
83		}
84	}
85
86	xa_destroy(&array);
87}
88