xref: /linux/tools/testing/selftests/futex/functional/futex_wait_wouldblock.c (revision fd7d598270724cc787982ea48bbe17ad383a8b7f)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /******************************************************************************
3  *
4  *   Copyright © International Business Machines  Corp., 2009
5  *
6  * DESCRIPTION
7  *      Test if FUTEX_WAIT op returns -EWOULDBLOCK if the futex value differs
8  *      from the expected one.
9  *
10  * AUTHOR
11  *      Gowrishankar <gowrishankar.m@in.ibm.com>
12  *
13  * HISTORY
14  *      2009-Nov-14: Initial version by Gowrishankar <gowrishankar.m@in.ibm.com>
15  *
16  *****************************************************************************/
17 
18 #include <errno.h>
19 #include <getopt.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <time.h>
24 #include "futextest.h"
25 #include "futex2test.h"
26 #include "logging.h"
27 
28 #define TEST_NAME "futex-wait-wouldblock"
29 #define timeout_ns 100000
30 
31 void usage(char *prog)
32 {
33 	printf("Usage: %s\n", prog);
34 	printf("  -c	Use color\n");
35 	printf("  -h	Display this help message\n");
36 	printf("  -v L	Verbosity level: %d=QUIET %d=CRITICAL %d=INFO\n",
37 	       VQUIET, VCRITICAL, VINFO);
38 }
39 
40 int main(int argc, char *argv[])
41 {
42 	struct timespec to = {.tv_sec = 0, .tv_nsec = timeout_ns};
43 	futex_t f1 = FUTEX_INITIALIZER;
44 	int res, ret = RET_PASS;
45 	int c;
46 	struct futex_waitv waitv = {
47 			.uaddr = (uintptr_t)&f1,
48 			.val = f1+1,
49 			.flags = FUTEX_32,
50 			.__reserved = 0
51 		};
52 
53 	while ((c = getopt(argc, argv, "cht:v:")) != -1) {
54 		switch (c) {
55 		case 'c':
56 			log_color(1);
57 			break;
58 		case 'h':
59 			usage(basename(argv[0]));
60 			exit(0);
61 		case 'v':
62 			log_verbosity(atoi(optarg));
63 			break;
64 		default:
65 			usage(basename(argv[0]));
66 			exit(1);
67 		}
68 	}
69 
70 	ksft_print_header();
71 	ksft_set_plan(2);
72 	ksft_print_msg("%s: Test the unexpected futex value in FUTEX_WAIT\n",
73 	       basename(argv[0]));
74 
75 	info("Calling futex_wait on f1: %u @ %p with val=%u\n", f1, &f1, f1+1);
76 	res = futex_wait(&f1, f1+1, &to, FUTEX_PRIVATE_FLAG);
77 	if (!res || errno != EWOULDBLOCK) {
78 		ksft_test_result_fail("futex_wait returned: %d %s\n",
79 				      res ? errno : res,
80 				      res ? strerror(errno) : "");
81 		ret = RET_FAIL;
82 	} else {
83 		ksft_test_result_pass("futex_wait\n");
84 	}
85 
86 	if (clock_gettime(CLOCK_MONOTONIC, &to)) {
87 		error("clock_gettime failed\n", errno);
88 		return errno;
89 	}
90 
91 	to.tv_nsec += timeout_ns;
92 
93 	if (to.tv_nsec >= 1000000000) {
94 		to.tv_sec++;
95 		to.tv_nsec -= 1000000000;
96 	}
97 
98 	info("Calling futex_waitv on f1: %u @ %p with val=%u\n", f1, &f1, f1+1);
99 	res = futex_waitv(&waitv, 1, 0, &to, CLOCK_MONOTONIC);
100 	if (!res || errno != EWOULDBLOCK) {
101 		ksft_test_result_pass("futex_waitv returned: %d %s\n",
102 				      res ? errno : res,
103 				      res ? strerror(errno) : "");
104 		ret = RET_FAIL;
105 	} else {
106 		ksft_test_result_pass("futex_waitv\n");
107 	}
108 
109 	ksft_print_cnts();
110 	return ret;
111 }
112