sched.h revision 299526 
1/*-
2 * Copyright (c) 2010 Isilon Systems, Inc.
3 * Copyright (c) 2010 iX Systems, Inc.
4 * Copyright (c) 2010 Panasas, Inc.
5 * Copyright (c) 2013-2016 Mellanox Technologies, Ltd.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice unmodified, this list of conditions, and the following
13 *    disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 *
29 * $FreeBSD: head/sys/compat/linuxkpi/common/include/linux/sched.h 299526 2016-05-12 09:06:54Z hselasky $
30 */
31#ifndef	_LINUX_SCHED_H_
32#define	_LINUX_SCHED_H_
33
34#include <sys/param.h>
35#include <sys/systm.h>
36#include <sys/proc.h>
37#include <sys/sched.h>
38#include <sys/sleepqueue.h>
39
40#define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
41
42#define	TASK_RUNNING		0
43#define	TASK_INTERRUPTIBLE	1
44#define	TASK_UNINTERRUPTIBLE	2
45#define	TASK_DEAD		64
46#define	TASK_WAKEKILL		128
47#define	TASK_WAKING		256
48
49#define	TASK_SHOULD_STOP	1
50#define	TASK_STOPPED		2
51
52/*
53 * A task_struct is only provided for threads created by kthread() and
54 * file operation callbacks.
55 *
56 * Using these routines outside the above mentioned contexts will
57 * cause panics because no task_struct is assigned and td_retval[1] is
58 * overwritten by syscalls.
59 */
60struct task_struct {
61	struct	thread *task_thread;
62	int	(*task_fn)(void *data);
63	void	*task_data;
64	int	task_ret;
65	int	state;
66	int	should_stop;
67	pid_t	pid;
68	const char    *comm;
69};
70
71#define	current			task_struct_get(curthread)
72#define	task_struct_get(x)	((struct task_struct *)(uintptr_t)(x)->td_retval[1])
73#define	task_struct_fill(x, y) do {		\
74  	(y)->task_thread = (x);			\
75	(y)->comm = (x)->td_name;		\
76	(y)->pid = (x)->td_tid;			\
77} while (0)
78#define	task_struct_set(x, y)	(x)->td_retval[1] = (uintptr_t)(y)
79
80/* ensure the task_struct pointer fits into the td_retval[1] field */
81CTASSERT(sizeof(((struct thread *)0)->td_retval[1]) >= sizeof(uintptr_t));
82
83#define	set_current_state(x)						\
84	atomic_store_rel_int((volatile int *)&current->state, (x))
85#define	__set_current_state(x)	current->state = (x)
86
87
88#define	schedule()							\
89do {									\
90	void *c;							\
91									\
92	if (cold)							\
93		break;							\
94	c = curthread;							\
95	sleepq_lock(c);							\
96	if (current->state == TASK_INTERRUPTIBLE ||			\
97	    current->state == TASK_UNINTERRUPTIBLE) {			\
98		sleepq_add(c, NULL, "task", SLEEPQ_SLEEP, 0);		\
99		sleepq_wait(c, 0);					\
100	} else {							\
101		sleepq_release(c);					\
102		sched_relinquish(curthread);				\
103	}								\
104} while (0)
105
106#define	wake_up_process(x)						\
107do {									\
108	int wakeup_swapper;						\
109	void *c;							\
110									\
111	c = (x)->task_thread;						\
112	sleepq_lock(c);							\
113	(x)->state = TASK_RUNNING;					\
114	wakeup_swapper = sleepq_signal(c, SLEEPQ_SLEEP, 0, 0);		\
115	sleepq_release(c);						\
116	if (wakeup_swapper)						\
117		kick_proc0();						\
118} while (0)
119
120#define	cond_resched()	if (!cold)	sched_relinquish(curthread)
121
122#define	sched_yield()	sched_relinquish(curthread)
123
124static inline long
125schedule_timeout(signed long timeout)
126{
127	if (timeout < 0)
128		return 0;
129
130	pause("lstim", timeout);
131
132	return 0;
133}
134
135#endif	/* _LINUX_SCHED_H_ */
136