/* * Copyright (C) 2001-2004 Jakub Jermar * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * - The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include #include #include #include #include #include #include #include #include #include #include static semaphore_t sem; SPINLOCK_INITIALIZE(lock); static waitq_t can_start; __u32 seed = 0xdeadbeef; static __u32 random(__u32 max); static void consumer(void *arg); static void failed(void); __u32 random(__u32 max) { __u32 rc; spinlock_lock(&lock); rc = seed % max; seed = (((seed<<2) ^ (seed>>2)) * 487) + rc; spinlock_unlock(&lock); return rc; } void consumer(void *arg) { int rc, to; waitq_sleep(&can_start); to = random(20000); printf("cpu%d, tid %d down+ (%d)\n", CPU->id, THREAD->tid, to); rc = semaphore_down_timeout(&sem, to); if (SYNCH_FAILED(rc)) { printf("cpu%d, tid %d down!\n", CPU->id, THREAD->tid); return; } printf("cpu%d, tid %d down=\n", CPU->id, THREAD->tid); thread_usleep(random(30000)); semaphore_up(&sem); printf("cpu%d, tid %d up\n", CPU->id, THREAD->tid); } void failed(void) { printf("Test failed prematurely.\n"); thread_exit(); } void test(void) { __u32 i, k; printf("Semaphore test #2\n"); waitq_initialize(&can_start); semaphore_initialize(&sem, 5); for (; ;) { thread_t *thrd; k = random(7) + 1; printf("Creating %d consumers\n", k); for (i=0; i