drm/i915: Fix hangs on some broadwell machines
[dragonfly.git] / contrib / amd / amd / sched.c
CommitLineData
984263bc
MD
1/*
2 * Copyright (c) 1997-1999 Erez Zadok
3 * Copyright (c) 1990 Jan-Simon Pendry
4 * Copyright (c) 1990 Imperial College of Science, Technology & Medicine
5 * Copyright (c) 1990 The Regents of the University of California.
6 * All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Jan-Simon Pendry at Imperial College, London.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgment:
21 * This product includes software developed by the University of
22 * California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 * %W% (Berkeley) %G%
40 *
41 * $Id: sched.c,v 1.3 1999/01/13 23:31:01 ezk Exp $
42 *
43 */
44
45/*
46 * Process scheduler
47 */
48
49#ifdef HAVE_CONFIG_H
50# include <config.h>
51#endif /* HAVE_CONFIG_H */
52#include <am_defs.h>
53#include <amd.h>
54
55
56typedef struct pjob pjob;
57
58struct pjob {
59 qelem hdr; /* Linked list */
60 int pid; /* Process ID of job */
61 cb_fun cb_fun; /* Callback function */
62 voidp cb_closure; /* Closure for callback */
63 int w; /* everyone these days uses int, not a "union wait" */
64 voidp wchan; /* Wait channel */
65};
66
67/* globals */
68qelem proc_list_head = {&proc_list_head, &proc_list_head};
69qelem proc_wait_list = {&proc_wait_list, &proc_wait_list};
70int task_notify_todo;
71
72
73void
74ins_que(qelem *elem, qelem *pred)
75{
76 qelem *p = pred->q_forw;
77
78 elem->q_back = pred;
79 elem->q_forw = p;
80 pred->q_forw = elem;
81 p->q_back = elem;
82}
83
84
85void
86rem_que(qelem *elem)
87{
88 qelem *p = elem->q_forw;
89 qelem *p2 = elem->q_back;
90
91 p2->q_forw = p;
92 p->q_back = p2;
93}
94
95
96static pjob *
97sched_job(cb_fun cf, voidp ca)
98{
99 pjob *p = ALLOC(struct pjob);
100
101 p->cb_fun = cf;
102 p->cb_closure = ca;
103
104 /*
105 * Now place on wait queue
106 */
107 ins_que(&p->hdr, &proc_wait_list);
108
109 return p;
110}
111
112
113/*
114 * tf: The task to execute (ta is its arguments)
115 * cf: Continuation function (ca is its arguments)
116 */
117void
118run_task(task_fun tf, voidp ta, cb_fun cf, voidp ca)
119{
120 pjob *p = sched_job(cf, ca);
121#ifdef HAVE_SIGACTION
122 sigset_t new, mask;
123#else /* not HAVE_SIGACTION */
124 int mask;
125#endif /* not HAVE_SIGACTION */
126
127 p->wchan = (voidp) p;
128
129#ifdef HAVE_SIGACTION
130 sigemptyset(&new); /* initialize signal set we wish to block */
131 sigaddset(&new, SIGCHLD); /* only block on SIGCHLD */
132 sigprocmask(SIG_BLOCK, &new, &mask);
133#else /* not HAVE_SIGACTION */
134 mask = sigblock(sigmask(SIGCHLD));
135#endif /* not HAVE_SIGACTION */
136
137 if ((p->pid = background())) {
138#ifdef HAVE_SIGACTION
139 sigprocmask(SIG_SETMASK, &mask, NULL);
140#else /* not HAVE_SIGACTION */
141 sigsetmask(mask);
142#endif /* not HAVE_SIGACTION */
143 return;
144 }
145
146 /* child code runs here, parent have returned to caller */
147
148 exit((*tf) (ta));
149 /* firewall... */
150 abort();
151}
152
153
154/*
155 * Schedule a task to be run when woken up
156 */
157void
158sched_task(cb_fun cf, voidp ca, voidp wchan)
159{
160 /*
161 * Allocate a new task
162 */
163 pjob *p = sched_job(cf, ca);
164
165#ifdef DEBUG
166 dlog("SLEEP on %#lx", (unsigned long) wchan);
167#endif /* DEBUG */
168 p->wchan = wchan;
169 p->pid = 0;
170 memset((voidp) &p->w, 0, sizeof(p->w));
171}
172
173
174static void
175wakeupjob(pjob *p)
176{
177 rem_que(&p->hdr);
178 ins_que(&p->hdr, &proc_list_head);
179 task_notify_todo++;
180}
181
182
183void
184wakeup(voidp wchan)
185{
186 pjob *p, *p2;
187
188 if (!foreground)
189 return;
190
191 /*
192 * Can't user ITER() here because
193 * wakeupjob() juggles the list.
194 */
195 for (p = AM_FIRST(pjob, &proc_wait_list);
196 p2 = NEXT(pjob, p), p != HEAD(pjob, &proc_wait_list);
197 p = p2) {
198 if (p->wchan == wchan) {
199 wakeupjob(p);
200 }
201 }
202}
203
204
205void
206wakeup_task(int rc, int term, voidp cl)
207{
208 wakeup(cl);
209}
210
211
212/*
213 * Run any pending tasks.
214 * This must be called with SIGCHLD disabled
215 */
216void
217do_task_notify(void)
218{
219 /*
220 * Keep taking the first item off the list and processing it.
221 *
222 * Done this way because the the callback can, quite reasonably,
223 * queue a new task, so no local reference into the list can be
224 * held here.
225 */
226 while (AM_FIRST(pjob, &proc_list_head) != HEAD(pjob, &proc_list_head)) {
227 pjob *p = AM_FIRST(pjob, &proc_list_head);
228 rem_que(&p->hdr);
229 /*
230 * This job has completed
231 */
232 --task_notify_todo;
233
234 /*
235 * Do callback if it exists
236 */
237 if (p->cb_fun) {
238 /* these two trigraphs will ensure compatibility with strict POSIX.1 */
239 (*p->cb_fun) (WIFEXITED(p->w) ? WEXITSTATUS(p->w) : 0,
240 WIFSIGNALED(p->w) ? WTERMSIG(p->w) : 0,
241 p->cb_closure);
242 }
243 XFREE(p);
244 }
245}
246
247
248RETSIGTYPE
249sigchld(int sig)
250{
251 int w; /* everyone these days uses int, not a "union wait" */
252 int pid;
253
254#ifdef HAVE_WAITPID
255 while ((pid = waitpid((pid_t) -1, &w, WNOHANG)) > 0) {
256#else /* not HAVE_WAITPID */
257 while ((pid = wait3( &w, WNOHANG, (struct rusage *) 0)) > 0) {
258#endif /* not HAVE_WAITPID */
259 pjob *p, *p2;
260
261 if (WIFSIGNALED(w))
262 plog(XLOG_ERROR, "Process %d exited with signal %d",
263 pid, WTERMSIG(w));
264#ifdef DEBUG
265 else
266 dlog("Process %d exited with status %d",
267 pid, WEXITSTATUS(w));
268#endif /* DEBUG */
269
270 for (p = AM_FIRST(pjob, &proc_wait_list);
271 p2 = NEXT(pjob, p), p != HEAD(pjob, &proc_wait_list);
272 p = p2) {
273 if (p->pid == pid) {
274 p->w = w;
275 wakeupjob(p);
276 break;
277 }
278 } /* end of for loop */
279
280#ifdef DEBUG
281 if (!p)
282 dlog("can't locate task block for pid %d", pid);
283#endif /* DEBUG */
284
285 /*
286 * Must count down children inside the while loop, otherwise we won't
287 * count them all, and NumChild (and later backoff) will be set
288 * incorrectly. SH/RUNIT 940519.
289 */
290 if (--NumChild < 0)
291 NumChild = 0;
292 } /* end of "while wait..." loop */
293
294#ifdef REINSTALL_SIGNAL_HANDLER
295 signal(sig, sigchld);
296#endif /* REINSTALL_SIGNAL_HANDLER */
297
298 if (select_intr_valid)
299 longjmp(select_intr, sig);
300}