2 * Copyright (c) 2005 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
5 * by Sergey Glushchenko <deen@smz.com.ua>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
17 * 3. Neither the name of The DragonFly Project nor the names of its
18 * contributors may be used to endorse or promote products derived
19 * from this software without specific, prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * $DragonFly: src/sys/kern/kern_usched.c,v 1.1 2005/11/16 02:24:30 dillon Exp $
37 #include <sys/errno.h>
38 #include <sys/globaldata.h> /* curthread */
40 #include <sys/sysproto.h> /* struct usched_set_args */
41 #include <sys/systm.h> /* strcmp() */
42 #include <sys/usched.h>
44 static TAILQ_HEAD(, usched
) usched_list
= TAILQ_HEAD_INITIALIZER(usched_list
);
47 * Called from very low level boot code, i386/i386/machdep.c/init386().
48 * We cannot do anything fancy. no malloc's, no nothing other then
49 * static initialization.
55 * Add the bsd4 userland scheduler to the system.
57 usched_ctl(&usched_bsd4
, USCH_ADD
);
65 * Add/remove usched to/from list.
68 * usched - pointer to target scheduler
69 * action - addition or removal ?
76 usched_ctl(struct usched
*usched
, int action
)
78 struct usched
*item
; /* temporaly for TAILQ processing */
84 * Make sure it isn't already on the list
87 TAILQ_FOREACH(item
, &usched_list
, entry
) {
88 KKASSERT(item
!= usched
);
92 * Optional callback to the scheduler before we officially
95 if (usched
->usched_register
)
96 usched
->usched_register();
97 TAILQ_INSERT_TAIL(&usched_list
, usched
, entry
);
101 * Do not allow the default scheduler to be removed
103 if (strcmp(usched
->name
, "bsd4") == 0) {
107 TAILQ_FOREACH(item
, &usched_list
, entry
) {
112 if (item
->usched_unregister
)
113 item
->usched_unregister();
114 TAILQ_REMOVE(&usched_list
, item
, entry
);
127 * USCHED_SET(syscall)
130 * Setting up a proc's usched.
133 * name - usched's name
140 usched_set(struct usched_set_args
*uap
)
142 struct proc
*p
= curthread
->td_proc
;
143 struct usched
*item
; /* temporaly for TAILQ processing */
146 if ((error
= suser(curthread
)) != 0)
149 TAILQ_FOREACH(item
, &usched_list
, entry
) {
150 if (strcmp(item
->name
, uap
->name
) == 0)
155 * If the scheduler for a process is being changed, disassociate
156 * the old scheduler before switching to the new one.
158 * XXX we might have to add an additional ABI call to do a 'full
159 * disassociation' and another ABI call to do a 'full reassociation'
161 if (item
&& item
!= p
->p_usched
) {
162 p
->p_usched
->release_curproc(&p
->p_lwp
);
164 } else if (item
== NULL
) {