xref: /linux/tools/testing/selftests/futex/functional/futex_wait.c (revision 59e6295fac26b8e85c1ea859cdd89fa1e47519d7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright Collabora Ltd., 2021
4  *
5  * futex cmp requeue test by André Almeida <andrealmeid@collabora.com>
6  */
7 
8 #include <fcntl.h>
9 #include <pthread.h>
10 #include <stdlib.h>
11 #include <sys/shm.h>
12 #include <sys/mman.h>
13 
14 #include "futextest.h"
15 #include "kselftest_harness.h"
16 
17 #define timeout_ns  30000000
18 #define WAKE_WAIT_US 10000
19 #define SHM_PATH "futex_shm_file"
20 
21 void *futex;
22 
23 struct waiter_args {
24 	struct __test_metadata	*_metadata;
25 	unsigned int		flags;
26 };
27 
28 static void *waiterfn(void *arg)
29 {
30 	struct waiter_args *args = (struct waiter_args *)arg;
31 	struct __test_metadata *_metadata = args->_metadata;
32 	struct timespec to;
33 	int res;
34 
35 	to.tv_sec = 0;
36 	to.tv_nsec = timeout_ns;
37 
38 	res = futex_wait(futex, 0, &to, args->flags);
39 	if (res) {
40 		EXPECT_EQ(res, 0)
41 			TH_LOG("waiter failed errno %d: %s", errno, strerror(errno));
42 	}
43 
44 	free(args);
45 	return NULL;
46 }
47 
48 TEST(private_futex)
49 {
50 	struct waiter_args *args = malloc(sizeof(*args));
51 	u_int32_t f_private = 0;
52 	pthread_t waiter;
53 	int res;
54 
55 	args->_metadata = _metadata;
56 	args->flags = FUTEX_PRIVATE_FLAG;
57 	futex = &f_private;
58 
59 	/* Testing a private futex */
60 	TH_LOG("Calling private futex_wait on futex: %p", futex);
61 	ASSERT_EQ(pthread_create(&waiter, NULL, waiterfn, args), 0)
62 		TH_LOG("pthread_create failed");
63 
64 	usleep(WAKE_WAIT_US);
65 
66 	TH_LOG("Calling private futex_wake on futex: %p", futex);
67 	res = futex_wake(futex, 1, FUTEX_PRIVATE_FLAG);
68 	EXPECT_EQ(res, 1)
69 		TH_LOG("futex_wake private returned: %d %s", res, res < 0 ? strerror(errno) : "");
70 
71 	pthread_join(waiter, NULL);
72 }
73 
74 TEST(anon_page)
75 {
76 	struct waiter_args *args = malloc(sizeof(*args));
77 	u_int32_t *shared_data;
78 	pthread_t waiter;
79 	int res, shm_id;
80 
81 	args->_metadata = _metadata;
82 	args->flags = 0;
83 
84 	/* Testing an anon page shared memory */
85 	shm_id = shmget(IPC_PRIVATE, 4096, IPC_CREAT | 0666);
86 	if (shm_id < 0) {
87 		if (errno == ENOSYS) {
88 			free(args);
89 			SKIP(return, "shmget syscall not supported");
90 		}
91 		ASSERT_GE(shm_id, 0)
92 			TH_LOG("shmget failed: %s", strerror(errno));
93 	}
94 
95 	shared_data = shmat(shm_id, NULL, 0);
96 	if (shared_data == (void *)-1) {
97 		free(args);
98 		ASSERT_NE(shared_data, (void *)-1)
99 			TH_LOG("shmat failed: %s", strerror(errno));
100 	}
101 
102 	*shared_data = 0;
103 	futex = shared_data;
104 
105 	TH_LOG("Calling shared (page anon) futex_wait on futex: %p", futex);
106 	ASSERT_EQ(pthread_create(&waiter, NULL, waiterfn, args), 0)
107 		TH_LOG("pthread_create failed");
108 
109 	usleep(WAKE_WAIT_US);
110 
111 	TH_LOG("Calling shared (page anon) futex_wake on futex: %p", futex);
112 	res = futex_wake(futex, 1, 0);
113 	EXPECT_EQ(res, 1) {
114 		TH_LOG("futex_wake shared (page anon) returned: %d %s",
115 		       res, res < 0 ? strerror(errno) : "");
116 	}
117 
118 	pthread_join(waiter, NULL);
119 	shmdt(shared_data);
120 }
121 
122 TEST(file_backed)
123 {
124 	struct waiter_args *args = malloc(sizeof(*args));
125 	u_int32_t f_private = 0;
126 	pthread_t waiter;
127 	int res, fd;
128 	void *shm;
129 
130 	args->_metadata = _metadata;
131 	args->flags = 0;
132 
133 	/* Testing a file backed shared memory */
134 	fd = open(SHM_PATH, O_RDWR | O_CREAT, 0600);
135 	if (fd < 0) {
136 		free(args);
137 		ASSERT_GE(fd, 0)
138 			TH_LOG("open failed: %s", strerror(errno));
139 	}
140 
141 	if (ftruncate(fd, sizeof(f_private))) {
142 		free(args);
143 		close(fd);
144 		ASSERT_TRUE(0)
145 			TH_LOG("ftruncate failed: %s", strerror(errno));
146 	}
147 
148 	shm = mmap(NULL, sizeof(f_private), PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
149 	if (shm == MAP_FAILED) {
150 		free(args);
151 		close(fd);
152 		ASSERT_NE(shm, MAP_FAILED)
153 			TH_LOG("mmap failed: %s", strerror(errno));
154 	}
155 
156 	memcpy(shm, &f_private, sizeof(f_private));
157 
158 	futex = shm;
159 
160 	TH_LOG("Calling shared (file backed) futex_wait on futex: %p", futex);
161 	ASSERT_EQ(pthread_create(&waiter, NULL, waiterfn, args), 0)
162 		TH_LOG("pthread_create failed");
163 
164 	usleep(WAKE_WAIT_US);
165 
166 	TH_LOG("Calling shared (file backed) futex_wake on futex: %p", futex);
167 	res = futex_wake(shm, 1, 0);
168 	EXPECT_EQ(res, 1) {
169 		TH_LOG("futex_wake shared (file backed) returned: %d %s",
170 		       res, res < 0 ? strerror(errno) : "");
171 	}
172 
173 	pthread_join(waiter, NULL);
174 	munmap(shm, sizeof(f_private));
175 	remove(SHM_PATH);
176 	close(fd);
177 }
178 
179 TEST_HARNESS_MAIN
180