003 File Manager
Current Path:
/usr/src/tools/regression/kthread/kld
usr
/
src
/
tools
/
regression
/
kthread
/
kld
/
📁
..
📄
Makefile
(102 B)
📄
kthrdlk.c
(4.86 KB)
Editing: kthrdlk.c
/*- * Copyright (c) 2010 Giovanni Trematerra <giovanni.trematerra@gmail.com> * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. 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. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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. */ /* * PURPOSE: * * This kernel module helped to identify a deadlock in kthread * interface, also pointed out a race in kthread_exit function. * */ #include <sys/cdefs.h> __FBSDID("$FreeBSD$"); #include <sys/param.h> #include <sys/kernel.h> #include <sys/kthread.h> #include <sys/lock.h> #include <sys/module.h> #include <sys/mutex.h> #include <sys/systm.h> #include <sys/time.h> #ifdef TESTPAUSE_DEBUG #define DPRINTF(x) do { \ printf (x); \ } while (0) #else #define DPRINTF(x) #endif static struct mtx test_global_lock; static int global_condvar; static int test_thrcnt; volatile int QUIT; static void thr_suspender(void *arg) { struct thread *td = (struct thread *) arg; int error; for (;;) { if (QUIT == 1) break; error = kthread_suspend(td, 10*hz); if (error != 0 && QUIT == 0) { if (error == EWOULDBLOCK) panic("Ooops: kthread deadlock\n"); else panic("kthread_suspend error: %d\n", error); break; } } mtx_lock(&test_global_lock); test_thrcnt--; wakeup(&global_condvar); mtx_unlock(&test_global_lock); kthread_exit(); } static void thr_resumer(void *arg) { struct thread *td = (struct thread *) arg; int error; for (;;) { /* must be the last thread to exit */ if (QUIT == 1 && test_thrcnt == 1) break; error = kthread_resume(td); if (error != 0) panic("%s: error on kthread_resume. error: %d\n", __func__, error); } mtx_lock(&test_global_lock); test_thrcnt--; wakeup(&global_condvar); mtx_unlock(&test_global_lock); kthread_exit(); } static void thr_getsuspended(void *arg) { for (;;) { if (QUIT == 1) break; kthread_suspend_check(); } mtx_lock(&test_global_lock); test_thrcnt--; wakeup(&global_condvar); mtx_unlock(&test_global_lock); kthread_exit(); } static void kthrdlk_init(void) { struct proc *testproc; struct thread *newthr; int error; QUIT = 0; test_thrcnt = 3; mtx_init(&test_global_lock, "kthrdlk_lock", NULL, MTX_DEF); testproc = NULL; error = kproc_kthread_add(thr_getsuspended, NULL, &testproc, &newthr, 0, 0, "kthrdlk", "thr_getsuspended"); if (error != 0) panic("cannot start thr_getsuspended error: %d\n", error); error = kproc_kthread_add(thr_resumer, newthr, &testproc, NULL, 0, 0, "kthrdlk", "thr_resumer"); if (error != 0) panic("cannot start thr_resumer error: %d\n", error); error = kproc_kthread_add(thr_suspender, newthr, &testproc, NULL, 0, 0, "kthrdlk", "thr_suspender"); if (error != 0) panic("cannot start thr_suspender error: %d\n", error); } static void kthrdlk_done(void) { int ret; DPRINTF(("sending QUIT signal to the thrdlk threads\n")); /* wait kernel threads end */ mtx_lock(&test_global_lock); QUIT = 1; while (test_thrcnt != 0) { ret = mtx_sleep(&global_condvar, &test_global_lock, 0, "waiting thrs end", 30 * hz); if (ret == EWOULDBLOCK) { panic("some threads not die! remaining: %d", test_thrcnt); break; } } if (test_thrcnt == 0) DPRINTF(("All test_pause threads die\n")); mtx_destroy(&test_global_lock); } static int kthrdlk_handler(module_t mod, int /*modeventtype_t*/ what, void *arg) { switch (what) { case MOD_LOAD: kthrdlk_init(); uprintf("kthrdlk loaded!\n"); return (0); case MOD_UNLOAD: kthrdlk_done(); uprintf("Bye Bye! kthrdlk unloaded!\n"); return (0); } return (EOPNOTSUPP); } static moduledata_t mod_data= { "kthrdlk", kthrdlk_handler, 0 }; MODULE_VERSION(kthrdlk, 1); DECLARE_MODULE(kthrdlk, mod_data, SI_SUB_EXEC, SI_ORDER_ANY);
Upload File
Create Folder