| /****************************************************************************** |
| * |
| * Copyright © International Business Machines Corp., 2006-2008 |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * DESCRIPTION |
| * This test excercises the futex syscall op codes needed for requeuing |
| * priority inheritance aware POSIX condition variables and mutexes. |
| * |
| * AUTHORS |
| * Sripathi Kodi <sripathik@in.ibm.com> |
| * Darren Hart <dvhart@linux.intel.com> |
| * |
| * HISTORY |
| * 2008-Jan-13: Initial version by Sripathi Kodi <sripathik@in.ibm.com> |
| * 2009-Nov-6: futex test adaptation by Darren Hart <dvhart@linux.intel.com> |
| * |
| *****************************************************************************/ |
| |
| #include <errno.h> |
| #include <limits.h> |
| #include <pthread.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <signal.h> |
| #include <string.h> |
| #include "atomic.h" |
| #include "futextest.h" |
| #include "logging.h" |
| |
| #define TEST_NAME "futex-requeue-pi" |
| #define MAX_WAKE_ITERS 1000 |
| #define THREAD_MAX 10 |
| #define SIGNAL_PERIOD_US 100 |
| |
| atomic_t waiters_blocked = ATOMIC_INITIALIZER; |
| atomic_t waiters_woken = ATOMIC_INITIALIZER; |
| |
| futex_t f1 = FUTEX_INITIALIZER; |
| futex_t f2 = FUTEX_INITIALIZER; |
| futex_t wake_complete = FUTEX_INITIALIZER; |
| |
| /* Test option defaults */ |
| static long timeout_ns; |
| static int broadcast; |
| static int owner; |
| static int locked; |
| |
| struct thread_arg { |
| long id; |
| struct timespec *timeout; |
| int lock; |
| int ret; |
| }; |
| #define THREAD_ARG_INITIALIZER { 0, NULL, 0, 0 } |
| |
| void usage(char *prog) |
| { |
| printf("Usage: %s\n", prog); |
| printf(" -b Broadcast wakeup (all waiters)\n"); |
| printf(" -c Use color\n"); |
| printf(" -h Display this help message\n"); |
| printf(" -l Lock the pi futex across requeue\n"); |
| printf(" -o Use a third party pi futex owner during requeue (cancels -l)\n"); |
| printf(" -t N Timeout in nanoseconds (default: 0)\n"); |
| printf(" -v L Verbosity level: %d=QUIET %d=CRITICAL %d=INFO\n", |
| VQUIET, VCRITICAL, VINFO); |
| } |
| |
| int create_rt_thread(pthread_t *pth, void*(*func)(void *), void *arg, |
| int policy, int prio) |
| { |
| int ret; |
| struct sched_param schedp; |
| pthread_attr_t attr; |
| |
| pthread_attr_init(&attr); |
| memset(&schedp, 0, sizeof(schedp)); |
| |
| ret = pthread_attr_setinheritsched(&attr, PTHREAD_EXPLICIT_SCHED); |
| if (ret) { |
| error("pthread_attr_setinheritsched\n", ret); |
| return -1; |
| } |
| |
| ret = pthread_attr_setschedpolicy(&attr, policy); |
| if (ret) { |
| error("pthread_attr_setschedpolicy\n", ret); |
| return -1; |
| } |
| |
| schedp.sched_priority = prio; |
| ret = pthread_attr_setschedparam(&attr, &schedp); |
| if (ret) { |
| error("pthread_attr_setschedparam\n", ret); |
| return -1; |
| } |
| |
| ret = pthread_create(pth, &attr, func, arg); |
| if (ret) { |
| error("pthread_create\n", ret); |
| return -1; |
| } |
| return 0; |
| } |
| |
| |
| void *waiterfn(void *arg) |
| { |
| struct thread_arg *args = (struct thread_arg *)arg; |
| futex_t old_val; |
| |
| info("Waiter %ld: running\n", args->id); |
| /* Each thread sleeps for a different amount of time |
| * This is to avoid races, because we don't lock the |
| * external mutex here */ |
| usleep(1000 * (long)args->id); |
| |
| old_val = f1; |
| atomic_inc(&waiters_blocked); |
| info("Calling futex_wait_requeue_pi: %p (%u) -> %p\n", |
| &f1, f1, &f2); |
| args->ret = futex_wait_requeue_pi(&f1, old_val, &f2, args->timeout, |
| FUTEX_PRIVATE_FLAG); |
| |
| info("waiter %ld woke with %d %s\n", args->id, args->ret, |
| args->ret < 0 ? strerror(errno) : ""); |
| atomic_inc(&waiters_woken); |
| if (args->ret < 0) { |
| if (args->timeout && errno == ETIMEDOUT) |
| args->ret = 0; |
| else { |
| args->ret = RET_ERROR; |
| error("futex_wait_requeue_pi\n", errno); |
| } |
| futex_lock_pi(&f2, NULL, 0, FUTEX_PRIVATE_FLAG); |
| } |
| futex_unlock_pi(&f2, FUTEX_PRIVATE_FLAG); |
| |
| info("Waiter %ld: exiting with %d\n", args->id, args->ret); |
| pthread_exit((void *)&args->ret); |
| } |
| |
| void *broadcast_wakerfn(void *arg) |
| { |
| struct thread_arg *args = (struct thread_arg *)arg; |
| int nr_requeue = INT_MAX; |
| int task_count = 0; |
| futex_t old_val; |
| int nr_wake = 1; |
| int i = 0; |
| |
| info("Waker: waiting for waiters to block\n"); |
| while (waiters_blocked.val < THREAD_MAX) |
| usleep(1000); |
| usleep(1000); |
| |
| info("Waker: Calling broadcast\n"); |
| if (args->lock) { |
| info("Calling FUTEX_LOCK_PI on mutex=%x @ %p\n", f2, &f2); |
| futex_lock_pi(&f2, NULL, 0, FUTEX_PRIVATE_FLAG); |
| } |
| continue_requeue: |
| old_val = f1; |
| args->ret = futex_cmp_requeue_pi(&f1, old_val, &f2, nr_wake, nr_requeue, |
| FUTEX_PRIVATE_FLAG); |
| if (args->ret < 0) { |
| args->ret = RET_ERROR; |
| error("FUTEX_CMP_REQUEUE_PI failed\n", errno); |
| } else if (++i < MAX_WAKE_ITERS) { |
| task_count += args->ret; |
| if (task_count < THREAD_MAX - waiters_woken.val) |
| goto continue_requeue; |
| } else { |
| error("max broadcast iterations (%d) reached with %d/%d tasks woken or requeued\n", |
| 0, MAX_WAKE_ITERS, task_count, THREAD_MAX); |
| args->ret = RET_ERROR; |
| } |
| |
| futex_wake(&wake_complete, 1, FUTEX_PRIVATE_FLAG); |
| |
| if (args->lock) |
| futex_unlock_pi(&f2, FUTEX_PRIVATE_FLAG); |
| |
| if (args->ret > 0) |
| args->ret = task_count; |
| |
| info("Waker: exiting with %d\n", args->ret); |
| pthread_exit((void *)&args->ret); |
| } |
| |
| void *signal_wakerfn(void *arg) |
| { |
| struct thread_arg *args = (struct thread_arg *)arg; |
| unsigned int old_val; |
| int nr_requeue = 0; |
| int task_count = 0; |
| int nr_wake = 1; |
| int i = 0; |
| |
| info("Waker: waiting for waiters to block\n"); |
| while (waiters_blocked.val < THREAD_MAX) |
| usleep(1000); |
| usleep(1000); |
| |
| while (task_count < THREAD_MAX && waiters_woken.val < THREAD_MAX) { |
| info("task_count: %d, waiters_woken: %d\n", |
| task_count, waiters_woken.val); |
| if (args->lock) { |
| info("Calling FUTEX_LOCK_PI on mutex=%x @ %p\n", |
| f2, &f2); |
| futex_lock_pi(&f2, NULL, 0, FUTEX_PRIVATE_FLAG); |
| } |
| info("Waker: Calling signal\n"); |
| /* cond_signal */ |
| old_val = f1; |
| args->ret = futex_cmp_requeue_pi(&f1, old_val, &f2, |
| nr_wake, nr_requeue, |
| FUTEX_PRIVATE_FLAG); |
| if (args->ret < 0) |
| args->ret = -errno; |
| info("futex: %x\n", f2); |
| if (args->lock) { |
| info("Calling FUTEX_UNLOCK_PI on mutex=%x @ %p\n", |
| f2, &f2); |
| futex_unlock_pi(&f2, FUTEX_PRIVATE_FLAG); |
| } |
| info("futex: %x\n", f2); |
| if (args->ret < 0) { |
| error("FUTEX_CMP_REQUEUE_PI failed\n", errno); |
| args->ret = RET_ERROR; |
| break; |
| } |
| |
| task_count += args->ret; |
| usleep(SIGNAL_PERIOD_US); |
| i++; |
| /* we have to loop at least THREAD_MAX times */ |
| if (i > MAX_WAKE_ITERS + THREAD_MAX) { |
| error("max signaling iterations (%d) reached, giving up on pending waiters.\n", |
| 0, MAX_WAKE_ITERS + THREAD_MAX); |
| args->ret = RET_ERROR; |
| break; |
| } |
| } |
| |
| futex_wake(&wake_complete, 1, FUTEX_PRIVATE_FLAG); |
| |
| if (args->ret >= 0) |
| args->ret = task_count; |
| |
| info("Waker: exiting with %d\n", args->ret); |
| info("Waker: waiters_woken: %d\n", waiters_woken.val); |
| pthread_exit((void *)&args->ret); |
| } |
| |
| void *third_party_blocker(void *arg) |
| { |
| struct thread_arg *args = (struct thread_arg *)arg; |
| int ret2 = 0; |
| |
| args->ret = futex_lock_pi(&f2, NULL, 0, FUTEX_PRIVATE_FLAG); |
| if (args->ret) |
| goto out; |
| args->ret = futex_wait(&wake_complete, wake_complete, NULL, |
| FUTEX_PRIVATE_FLAG); |
| ret2 = futex_unlock_pi(&f2, FUTEX_PRIVATE_FLAG); |
| |
| out: |
| if (args->ret || ret2) { |
| error("third_party_blocker() futex error", 0); |
| args->ret = RET_ERROR; |
| } |
| |
| pthread_exit((void *)&args->ret); |
| } |
| |
| int unit_test(int broadcast, long lock, int third_party_owner, long timeout_ns) |
| { |
| void *(*wakerfn)(void *) = signal_wakerfn; |
| struct thread_arg blocker_arg = THREAD_ARG_INITIALIZER; |
| struct thread_arg waker_arg = THREAD_ARG_INITIALIZER; |
| pthread_t waiter[THREAD_MAX], waker, blocker; |
| struct timespec ts, *tsp = NULL; |
| struct thread_arg args[THREAD_MAX]; |
| int *waiter_ret; |
| int i, ret = RET_PASS; |
| |
| if (timeout_ns) { |
| time_t secs; |
| |
| info("timeout_ns = %ld\n", timeout_ns); |
| ret = clock_gettime(CLOCK_MONOTONIC, &ts); |
| secs = (ts.tv_nsec + timeout_ns) / 1000000000; |
| ts.tv_nsec = ((int64_t)ts.tv_nsec + timeout_ns) % 1000000000; |
| ts.tv_sec += secs; |
| info("ts.tv_sec = %ld\n", ts.tv_sec); |
| info("ts.tv_nsec = %ld\n", ts.tv_nsec); |
| tsp = &ts; |
| } |
| |
| if (broadcast) |
| wakerfn = broadcast_wakerfn; |
| |
| if (third_party_owner) { |
| if (create_rt_thread(&blocker, third_party_blocker, |
| (void *)&blocker_arg, SCHED_FIFO, 1)) { |
| error("Creating third party blocker thread failed\n", |
| errno); |
| ret = RET_ERROR; |
| goto out; |
| } |
| } |
| |
| atomic_set(&waiters_woken, 0); |
| for (i = 0; i < THREAD_MAX; i++) { |
| args[i].id = i; |
| args[i].timeout = tsp; |
| info("Starting thread %d\n", i); |
| if (create_rt_thread(&waiter[i], waiterfn, (void *)&args[i], |
| SCHED_FIFO, 1)) { |
| error("Creating waiting thread failed\n", errno); |
| ret = RET_ERROR; |
| goto out; |
| } |
| } |
| waker_arg.lock = lock; |
| if (create_rt_thread(&waker, wakerfn, (void *)&waker_arg, |
| SCHED_FIFO, 1)) { |
| error("Creating waker thread failed\n", errno); |
| ret = RET_ERROR; |
| goto out; |
| } |
| |
| /* Wait for threads to finish */ |
| /* Store the first error or failure encountered in waiter_ret */ |
| waiter_ret = &args[0].ret; |
| for (i = 0; i < THREAD_MAX; i++) |
| pthread_join(waiter[i], |
| *waiter_ret ? NULL : (void **)&waiter_ret); |
| |
| if (third_party_owner) |
| pthread_join(blocker, NULL); |
| pthread_join(waker, NULL); |
| |
| out: |
| if (!ret) { |
| if (*waiter_ret) |
| ret = *waiter_ret; |
| else if (waker_arg.ret < 0) |
| ret = waker_arg.ret; |
| else if (blocker_arg.ret) |
| ret = blocker_arg.ret; |
| } |
| |
| return ret; |
| } |
| |
| int main(int argc, char *argv[]) |
| { |
| int c, ret; |
| |
| while ((c = getopt(argc, argv, "bchlot:v:")) != -1) { |
| switch (c) { |
| case 'b': |
| broadcast = 1; |
| break; |
| case 'c': |
| log_color(1); |
| break; |
| case 'h': |
| usage(basename(argv[0])); |
| exit(0); |
| case 'l': |
| locked = 1; |
| break; |
| case 'o': |
| owner = 1; |
| locked = 0; |
| break; |
| case 't': |
| timeout_ns = atoi(optarg); |
| break; |
| case 'v': |
| log_verbosity(atoi(optarg)); |
| break; |
| default: |
| usage(basename(argv[0])); |
| exit(1); |
| } |
| } |
| |
| ksft_print_header(); |
| ksft_print_msg("%s: Test requeue functionality\n", basename(argv[0])); |
| ksft_print_msg( |
| "\tArguments: broadcast=%d locked=%d owner=%d timeout=%ldns\n", |
| broadcast, locked, owner, timeout_ns); |
| |
| /* |
| * FIXME: unit_test is obsolete now that we parse options and the |
| * various style of runs are done by run.sh - simplify the code and move |
| * unit_test into main() |
| */ |
| ret = unit_test(broadcast, locked, owner, timeout_ns); |
| |
| print_result(TEST_NAME, ret); |
| return ret; |
| } |