sched.h revision 1.17 
1/*	$NetBSD: sched.h,v 1.17 2021/12/19 01:51:27 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/errno.h>
44
45#define	TASK_COMM_LEN	MAXCOMLEN
46
47#define	MAX_SCHEDULE_TIMEOUT	(INT_MAX/2)	/* paranoia */
48
49#define	TASK_UNINTERRUPTIBLE	__BIT(0)
50
51#define	current	curproc
52
53static inline pid_t
54task_pid_nr(struct proc *p)
55{
56	return p->p_pid;
57}
58
59static inline long
60schedule_timeout_uninterruptible(long timeout)
61{
62	long remain;
63	int start, end;
64
65	if (cold) {
66		unsigned us;
67		if (hz <= 1000) {
68			unsigned ms = hztoms(MIN((unsigned long)timeout,
69			    mstohz(INT_MAX)));
70			us = MIN(ms, INT_MAX/1000)*1000;
71		} else if (hz <= 1000000) {
72			us = MIN(timeout, (INT_MAX/1000000)/hz)*hz*1000000;
73		} else {
74			us = timeout/(1000000/hz);
75		}
76		DELAY(us);
77		return 0;
78	}
79
80	start = getticks();
81	/* Caller is expected to loop anyway, so no harm in truncating.  */
82	(void)kpause("loonix", false /*!intr*/, MIN(timeout, INT_MAX), NULL);
83	end = getticks();
84
85	remain = timeout - (end - start);
86	return remain > 0 ? remain : 0;
87}
88
89static inline bool
90need_resched(void)
91{
92	/* XXX kpreempt_disable */
93	/* XXX ci_want_resched */
94	return (curcpu()->ci_schedstate.spc_flags & SPCF_SHOULDYIELD);
95}
96
97static inline void
98cond_resched(void)
99{
100
101	preempt_point();
102}
103
104static inline bool
105signal_pending_state(int state, struct proc *p)
106{
107
108	KASSERT(p == current);
109	if (state & TASK_UNINTERRUPTIBLE)
110		return false;
111	return sigispending(curlwp, 0);
112}
113
114#endif  /* _LINUX_SCHED_H_ */
115