1 /*-
2  * Copyright (c) 2010 Isilon Systems, Inc.
3  * Copyright (c) 2010 iX Systems, Inc.
4  * Copyright (c) 2010 Panasas, Inc.
5  * Copyright (c) 2013-2017 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  * $FreeBSD$
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 #include <linux/types.h>
41 #include <linux/compat.h>
42 #include <linux/completion.h>
43 #include <linux/pid.h>
44 #include <linux/slab.h>
45 #include <linux/mm_types.h>
46 
47 #include <asm/atomic.h>
48 
49 #define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
50 
51 #define	TASK_RUNNING		0
52 #define	TASK_INTERRUPTIBLE	1
53 #define	TASK_UNINTERRUPTIBLE	2
54 #define	TASK_DEAD		64
55 #define	TASK_WAKEKILL		128
56 #define	TASK_WAKING		256
57 
58 struct task_struct {
59 	struct thread *task_thread;
60 	struct mm_struct *mm;
61 	linux_task_fn_t *task_fn;
62 	void   *task_data;
63 	int	task_ret;
64 	atomic_t usage;
65 	int	state;
66 	atomic_t kthread_flags;
67 	pid_t	pid;	/* BSD thread ID */
68 	const char    *comm;
69 	void   *bsd_ioctl_data;
70 	unsigned bsd_ioctl_len;
71 	struct completion parked;
72 	struct completion exited;
73 };
74 
75 #define	current		((struct task_struct *)curthread->td_lkpi_task)
76 
77 #define	task_pid_group_leader(task) \
78 	FIRST_THREAD_IN_PROC((task)->task_thread->td_proc)->td_tid
79 #define	task_pid(task)		((task)->pid)
80 #define	task_pid_nr(task)	((task)->pid)
81 #define	get_pid(x)		(x)
82 #define	put_pid(x)		do { } while (0)
83 #define	current_euid()	(curthread->td_ucred->cr_uid)
84 
85 #define	set_current_state(x)						\
86 	atomic_store_rel_int((volatile int *)&current->state, (x))
87 #define	__set_current_state(x)	current->state = (x)
88 
89 static inline void
90 get_task_struct(struct task_struct *task)
91 {
92 	atomic_inc(&task->usage);
93 }
94 
95 static inline void
96 put_task_struct(struct task_struct *task)
97 {
98 	if (atomic_dec_and_test(&task->usage))
99 		linux_free_current(task);
100 }
101 
102 #define	schedule()							\
103 do {									\
104 	void *c;							\
105 									\
106 	if (cold || SCHEDULER_STOPPED())				\
107 		break;							\
108 	c = curthread;							\
109 	sleepq_lock(c);							\
110 	if (current->state == TASK_INTERRUPTIBLE ||			\
111 	    current->state == TASK_UNINTERRUPTIBLE) {			\
112 		sleepq_add(c, NULL, "task", SLEEPQ_SLEEP, 0);		\
113 		sleepq_wait(c, 0);					\
114 	} else {							\
115 		sleepq_release(c);					\
116 		sched_relinquish(curthread);				\
117 	}								\
118 } while (0)
119 
120 #define	wake_up_process(x)						\
121 do {									\
122 	int wakeup_swapper;						\
123 	void *c;							\
124 									\
125 	c = (x)->task_thread;						\
126 	sleepq_lock(c);							\
127 	(x)->state = TASK_RUNNING;					\
128 	wakeup_swapper = sleepq_signal(c, SLEEPQ_SLEEP, 0, 0);		\
129 	sleepq_release(c);						\
130 	if (wakeup_swapper)						\
131 		kick_proc0();						\
132 } while (0)
133 
134 #define	cond_resched()	if (!cold)	sched_relinquish(curthread)
135 
136 #define	sched_yield()	sched_relinquish(curthread)
137 
138 static inline long
139 schedule_timeout(signed long timeout)
140 {
141 	if (timeout < 0)
142 		return 0;
143 
144 	pause("lstim", timeout);
145 
146 	return 0;
147 }
148 
149 #endif	/* _LINUX_SCHED_H_ */
150