1 /* $NetBSD: busypage.c,v 1.5 2011/08/07 14:03:15 rmind Exp $ */
4 * Copyright (c) 2010 The NetBSD Foundation, Inc.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND
17 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
18 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
23 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
25 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
26 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
27 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 #include <sys/cdefs.h>
32 __RCSID("$NetBSD: busypage.c,v 1.5 2011/08/07 14:03:15 rmind Exp $");
35 #include <sys/param.h>
36 #include <sys/condvar.h>
37 #include <sys/kthread.h>
38 #include <sys/mutex.h>
43 #include "kernspace.h"
45 static struct uvm_object *uobj;
46 static struct vm_page *testpg;
47 static kcondvar_t tcv;
49 static bool threadrun = false;
55 mutex_enter(uobj->vmobjlock);
58 testpg->flags |= PG_WANTED;
59 UVM_UNLOCK_AND_WAIT(testpg, uobj->vmobjlock, false, "tw", 0);
69 cv_init(&tcv, "napina");
71 uobj = uao_create(1, 0);
72 mutex_enter(uobj->vmobjlock);
73 testpg = uvm_pagealloc(uobj, 0, NULL, 0);
74 mutex_exit(uobj->vmobjlock);
76 panic("couldn't create vm page");
78 rv = kthread_create(PRI_NONE, KTHREAD_MUSTJOIN | KTHREAD_MPSAFE, NULL,
79 thread, NULL, &newl, "jointest");
81 panic("thread creation failed: %d", rv);
83 mutex_enter(uobj->vmobjlock);
85 cv_wait(&tcv, uobj->vmobjlock);
87 uvm_page_unbusy(&testpg, 1);
88 mutex_exit(uobj->vmobjlock);
90 rv = kthread_join(newl);
92 panic("thread join failed: %d", rv);