tests/rump/kernspace/busypage.c

   1 /*      $NetBSD: busypage.c,v 1.5 2011/08/07 14:03:15 rmind Exp $       */
   2
   3 /*-
   4  * Copyright (c) 2010 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  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.
  15  *
  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.
  28  */
  29
  30 #include <sys/cdefs.h>
  31 #if !defined(lint)
  32 __RCSID("$NetBSD: busypage.c,v 1.5 2011/08/07 14:03:15 rmind Exp $");
  33 #endif /* !lint */
  34
  35 #include <sys/param.h>
  36 #include <sys/condvar.h>
  37 #include <sys/kthread.h>
  38 #include <sys/mutex.h>
  39 #include <sys/proc.h>
  40
  41 #include <uvm/uvm.h>
  42
  43 #include "kernspace.h"
  44
  45 static struct uvm_object *uobj;
  46 static struct vm_page *testpg;
  47 static kcondvar_t tcv;
  48
  49 static bool threadrun = false;
  50
  51 static void
  52 thread(void *arg)
  53 {
  54
  55         mutex_enter(uobj->vmobjlock);
  56         threadrun = true;
  57         cv_signal(&tcv);
  58         testpg->flags |= PG_WANTED;
  59         UVM_UNLOCK_AND_WAIT(testpg, uobj->vmobjlock, false, "tw", 0);
  60         kthread_exit(0);
  61 }
  62
  63 void
  64 rumptest_busypage()
  65 {
  66         struct lwp *newl;
  67         int rv;
  68
  69         cv_init(&tcv, "napina");
  70
  71         uobj = uao_create(1, 0);
  72         mutex_enter(uobj->vmobjlock);
  73         testpg = uvm_pagealloc(uobj, 0, NULL, 0);
  74         mutex_exit(uobj->vmobjlock);
  75         if (testpg == NULL)
  76                 panic("couldn't create vm page");
  77
  78         rv = kthread_create(PRI_NONE, KTHREAD_MUSTJOIN | KTHREAD_MPSAFE, NULL,
  79             thread, NULL, &newl, "jointest");
  80         if (rv)
  81                 panic("thread creation failed: %d", rv);
  82
  83         mutex_enter(uobj->vmobjlock);
  84         while (!threadrun)
  85                 cv_wait(&tcv, uobj->vmobjlock);
  86
  87         uvm_page_unbusy(&testpg, 1);
  88         mutex_exit(uobj->vmobjlock);
  89
  90         rv = kthread_join(newl);
  91         if (rv)
  92                 panic("thread join failed: %d", rv);
  93
  94 }