1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/kernel.h>
3 #include <linux/gfp.h>
4 #include <linux/slab.h>
5 #include <linux/radix-tree.h>
6 #include <linux/rcupdate.h>
7 #include <stdlib.h>
8 #include <pthread.h>
9 #include <stdio.h>
10 #include <assert.h>
11 
12 #include "regression.h"
13 
14 static pthread_barrier_t worker_barrier;
15 static int obj0, obj1;
16 static RADIX_TREE(mt_tree, GFP_KERNEL);
17 
reader_fn(void * arg)18 static void *reader_fn(void *arg)
19 {
20 	int i;
21 	void *entry;
22 
23 	rcu_register_thread();
24 	pthread_barrier_wait(&worker_barrier);
25 
26 	for (i = 0; i < 1000000; i++) {
27 		rcu_read_lock();
28 		entry = radix_tree_lookup(&mt_tree, 0);
29 		rcu_read_unlock();
30 		if (entry != &obj0) {
31 			printf("iteration %d bad entry = %p\n", i, entry);
32 			abort();
33 		}
34 	}
35 
36 	rcu_unregister_thread();
37 
38 	return NULL;
39 }
40 
writer_fn(void * arg)41 static void *writer_fn(void *arg)
42 {
43 	int i;
44 
45 	rcu_register_thread();
46 	pthread_barrier_wait(&worker_barrier);
47 
48 	for (i = 0; i < 1000000; i++) {
49 		radix_tree_insert(&mt_tree, 1, &obj1);
50 		radix_tree_delete(&mt_tree, 1);
51 	}
52 
53 	rcu_unregister_thread();
54 
55 	return NULL;
56 }
57 
regression4_test(void)58 void regression4_test(void)
59 {
60 	pthread_t reader, writer;
61 
62 	printv(1, "regression test 4 starting\n");
63 
64 	radix_tree_insert(&mt_tree, 0, &obj0);
65 	pthread_barrier_init(&worker_barrier, NULL, 2);
66 
67 	if (pthread_create(&reader, NULL, reader_fn, NULL) ||
68 	    pthread_create(&writer, NULL, writer_fn, NULL)) {
69 		perror("pthread_create");
70 		exit(1);
71 	}
72 
73 	if (pthread_join(reader, NULL) || pthread_join(writer, NULL)) {
74 		perror("pthread_join");
75 		exit(1);
76 	}
77 
78 	printv(1, "regression test 4 passed\n");
79 }
80