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 1.7 2006/12/23 00:35:04 swildner 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>
43 #include <machine/smp.h>
45 static TAILQ_HEAD(, usched) usched_list = TAILQ_HEAD_INITIALIZER(usched_list);
48 * Called from very low level boot code, i386/i386/machdep.c/init386().
49 * We cannot do anything fancy. no malloc's, no nothing other then
50 * static initialization.
57 defsched = kgetenv("kern.user_scheduler");
60 * Add various userland schedulers to the system.
62 usched_ctl(&usched_bsd4, USCH_ADD);
63 usched_ctl(&usched_dummy, USCH_ADD);
64 if (defsched == NULL )
66 if (strcmp(defsched, "bsd4") == 0)
68 kprintf("WARNING: Running dummy userland scheduler\n");
69 return(&usched_dummy);
76 * Add/remove usched to/from list.
79 * usched - pointer to target scheduler
80 * action - addition or removal ?
87 usched_ctl(struct usched *usched, int action)
89 struct usched *item; /* temporaly for TAILQ processing */
95 * Make sure it isn't already on the list
98 TAILQ_FOREACH(item, &usched_list, entry) {
99 KKASSERT(item != usched);
103 * Optional callback to the scheduler before we officially
104 * add it to the list.
106 if (usched->usched_register)
107 usched->usched_register();
108 TAILQ_INSERT_TAIL(&usched_list, usched, entry);
112 * Do not allow the default scheduler to be removed
114 if (strcmp(usched->name, "bsd4") == 0) {
118 TAILQ_FOREACH(item, &usched_list, entry) {
123 if (item->usched_unregister)
124 item->usched_unregister();
125 TAILQ_REMOVE(&usched_list, item, entry);
138 * USCHED_SET(syscall)
141 * Setting up a proc's usched.
153 sys_usched_set(struct usched_set_args *uap)
155 struct proc *p = curthread->td_proc;
156 struct usched *item; /* temporaly for TAILQ processing */
158 char buffer[NAME_LENGTH];
163 if ((error = suser(curthread)) != 0)
166 if (uap->pid != 0 && uap->pid != curthread->td_proc->p_pid)
169 lp = curthread->td_lwp;
171 case USCHED_SET_SCHEDULER:
172 if ((error = copyinstr(uap->data, buffer, sizeof(buffer),
175 TAILQ_FOREACH(item, &usched_list, entry) {
176 if ((strcmp(item->name, buffer) == 0))
181 * If the scheduler for a process is being changed, disassociate
182 * the old scheduler before switching to the new one.
184 * XXX we might have to add an additional ABI call to do a 'full
185 * disassociation' and another ABI call to do a 'full
188 if (item && item != p->p_usched) {
189 p->p_usched->release_curproc(&p->p_lwp);
191 } else if (item == NULL) {
196 if (uap->bytes != sizeof(int))
198 error = copyin(uap->data, &cpuid, sizeof(int));
201 if ((smp_active_mask & (1 << cpuid)) == 0) {
205 lp->lwp_cpumask = 1 << cpuid;
206 if (cpuid != mycpu->gd_cpuid)
207 lwkt_migratecpu(cpuid);
210 if (uap->bytes != sizeof(int))
212 error = copyin(uap->data, &cpuid, sizeof(int));
215 if (!(smp_active_mask & (1 << cpuid))) {
219 lp->lwp_cpumask |= 1 << cpuid;
222 if (uap->bytes != sizeof(int))
224 error = copyin(uap->data, &cpuid, sizeof(int));
227 lp = curthread->td_lwp;
228 mask = lp->lwp_cpumask & smp_active_mask & ~(1 << cpuid);
232 lp->lwp_cpumask &= ~(1 << cpuid);
233 if ((lp->lwp_cpumask & mycpu->gd_cpumask) == 0) {
234 cpuid = bsfl(lp->lwp_cpumask & smp_active_mask);
235 lwkt_migratecpu(cpuid);