1 /******************************************************************************
3 * Copyright © International Business Machines Corp., 2006-2008
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
11 * This test exercises the futex_wait_requeue_pi() signal handling both
12 * before and after the requeue. The first should be restarted by the
13 * kernel. The latter should return EWOULDBLOCK to the waiter.
16 * Darren Hart <dvhart@linux.intel.com>
19 * 2008-May-5: Initial version by Darren Hart <dvhart@linux.intel.com>
21 *****************************************************************************/
32 #include "futextest.h"
35 #define TEST_NAME "futex-requeue-pi-signal-restart"
38 futex_t f1 = FUTEX_INITIALIZER;
39 futex_t f2 = FUTEX_INITIALIZER;
40 atomic_t requeued = ATOMIC_INITIALIZER;
44 void usage(char *prog)
46 printf("Usage: %s\n", prog);
47 printf(" -c Use color\n");
48 printf(" -h Display this help message\n");
49 printf(" -v L Verbosity level: %d=QUIET %d=CRITICAL %d=INFO\n",
50 VQUIET, VCRITICAL, VINFO);
53 int create_rt_thread(pthread_t *pth, void*(*func)(void *), void *arg,
56 struct sched_param schedp;
60 pthread_attr_init(&attr);
61 memset(&schedp, 0, sizeof(schedp));
63 ret = pthread_attr_setinheritsched(&attr, PTHREAD_EXPLICIT_SCHED);
65 error("pthread_attr_setinheritsched\n", ret);
69 ret = pthread_attr_setschedpolicy(&attr, policy);
71 error("pthread_attr_setschedpolicy\n", ret);
75 schedp.sched_priority = prio;
76 ret = pthread_attr_setschedparam(&attr, &schedp);
78 error("pthread_attr_setschedparam\n", ret);
82 ret = pthread_create(pth, &attr, func, arg);
84 error("pthread_create\n", ret);
90 void handle_signal(int signo)
92 info("signal received %s requeue\n",
93 requeued.val ? "after" : "prior to");
96 void *waiterfn(void *arg)
101 waiter_ret = RET_PASS;
103 info("Waiter running\n");
104 info("Calling FUTEX_LOCK_PI on f2=%x @ %p\n", f2, &f2);
106 res = futex_wait_requeue_pi(&f1, old_val, &(f2), NULL,
108 if (!requeued.val || errno != EWOULDBLOCK) {
109 fail("unexpected return from futex_wait_requeue_pi: %d (%s)\n",
110 res, strerror(errno));
111 info("w2:futex: %x\n", f2);
113 futex_unlock_pi(&f2, FUTEX_PRIVATE_FLAG);
114 waiter_ret = RET_FAIL;
117 info("Waiter exiting with %d\n", waiter_ret);
122 int main(int argc, char *argv[])
124 unsigned int old_val;
127 int c, res, ret = RET_PASS;
129 while ((c = getopt(argc, argv, "chv:")) != -1) {
135 usage(basename(argv[0]));
138 log_verbosity(atoi(optarg));
141 usage(basename(argv[0]));
147 ksft_print_msg("%s: Test signal handling during requeue_pi\n",
149 ksft_print_msg("\tArguments: <none>\n");
151 sa.sa_handler = handle_signal;
152 sigemptyset(&sa.sa_mask);
154 if (sigaction(SIGUSR1, &sa, NULL)) {
155 error("sigaction\n", errno);
159 info("m1:f2: %x\n", f2);
160 info("Creating waiter\n");
161 res = create_rt_thread(&waiter, waiterfn, NULL, SCHED_FIFO, 1);
163 error("Creating waiting thread failed", res);
168 info("Calling FUTEX_LOCK_PI on f2=%x @ %p\n", f2, &f2);
169 info("m2:f2: %x\n", f2);
170 futex_lock_pi(&f2, 0, 0, FUTEX_PRIVATE_FLAG);
171 info("m3:f2: %x\n", f2);
175 * signal the waiter before requeue, waiter should automatically
176 * restart futex_wait_requeue_pi() in the kernel. Wait for the
177 * waiter to block on f1 again.
179 info("Issuing SIGUSR1 to waiter\n");
180 pthread_kill(waiter, SIGUSR1);
183 info("Requeueing waiter via FUTEX_CMP_REQUEUE_PI\n");
185 res = futex_cmp_requeue_pi(&f1, old_val, &(f2), 1, 0,
188 * If res is non-zero, we either requeued the waiter or hit an
189 * error, break out and handle it. If it is zero, then the
190 * signal may have hit before the the waiter was blocked on f1.
194 atomic_set(&requeued, 1);
196 } else if (res < 0) {
197 error("FUTEX_CMP_REQUEUE_PI failed\n", errno);
202 info("m4:f2: %x\n", f2);
205 * Signal the waiter after requeue, waiter should return from
206 * futex_wait_requeue_pi() with EWOULDBLOCK. Join the thread here so the
207 * futex_unlock_pi() can't happen before the signal wakeup is detected
210 info("Issuing SIGUSR1 to waiter\n");
211 pthread_kill(waiter, SIGUSR1);
212 info("Waiting for waiter to return\n");
213 pthread_join(waiter, NULL);
215 info("Calling FUTEX_UNLOCK_PI on mutex=%x @ %p\n", f2, &f2);
216 futex_unlock_pi(&f2, FUTEX_PRIVATE_FLAG);
217 info("m5:f2: %x\n", f2);
220 if (ret == RET_PASS && waiter_ret)
223 print_result(TEST_NAME, ret);