sched.h revision 1.18 
1/*	$NetBSD: sched.h,v 1.18 2021/12/19 10:38:05 riastradh Exp $	*/
2
3/*-
4 * Copyright (c) 2013 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Taylor R. Campbell.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#ifndef _LINUX_SCHED_H_
33#define _LINUX_SCHED_H_
34
35#include <sys/param.h>
36#include <sys/cdefs.h>
37#include <sys/kernel.h>
38#include <sys/proc.h>
39
40#include <asm/param.h>
41#include <asm/barrier.h>
42#include <asm/processor.h>
43#include <linux/device.h>
44#include <linux/errno.h>
45
46struct seq_file;
47
48#define	TASK_COMM_LEN	MAXCOMLEN
49
50#define	MAX_SCHEDULE_TIMEOUT	(INT_MAX/2)	/* paranoia */
51
52#define	TASK_UNINTERRUPTIBLE	__BIT(0)
53
54#define	current	curproc
55
56static inline pid_t
57task_pid_nr(struct proc *p)
58{
59	return p->p_pid;
60}
61
62static inline long
63schedule_timeout_uninterruptible(long timeout)
64{
65	long remain;
66	int start, end;
67
68	if (cold) {
69		unsigned us;
70		if (hz <= 1000) {
71			unsigned ms = hztoms(MIN((unsigned long)timeout,
72			    mstohz(INT_MAX)));
73			us = MIN(ms, INT_MAX/1000)*1000;
74		} else if (hz <= 1000000) {
75			us = MIN(timeout, (INT_MAX/1000000)/hz)*hz*1000000;
76		} else {
77			us = timeout/(1000000/hz);
78		}
79		DELAY(us);
80		return 0;
81	}
82
83	start = getticks();
84	/* Caller is expected to loop anyway, so no harm in truncating.  */
85	(void)kpause("loonix", false /*!intr*/, MIN(timeout, INT_MAX), NULL);
86	end = getticks();
87
88	remain = timeout - (end - start);
89	return remain > 0 ? remain : 0;
90}
91
92static inline bool
93need_resched(void)
94{
95	/* XXX kpreempt_disable */
96	/* XXX ci_want_resched */
97	return (curcpu()->ci_schedstate.spc_flags & SPCF_SHOULDYIELD);
98}
99
100static inline void
101cond_resched(void)
102{
103
104	preempt_point();
105}
106
107static inline bool
108signal_pending_state(int state, struct proc *p)
109{
110
111	KASSERT(p == current);
112	if (state & TASK_UNINTERRUPTIBLE)
113		return false;
114	return sigispending(curlwp, 0);
115}
116
117#endif  /* _LINUX_SCHED_H_ */
118