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: &xas, index: 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, index: i, entry: xa_mk_value(v: i), GFP_KERNEL);
44 xa_set_mark(xa, index: i, XA_MARK_0);
45 }
46 for (i = 0; i < 100; i++)
47 xa_erase(xa, index: 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, index: 100, entry: xa_mk_value(v: 100), GFP_KERNEL);
65 xa_set_mark(&array, index: 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

source code of linux/tools/testing/radix-tree/iteration_check_2.c