sys/compat/linuxkpi/common/include/linux/sched.h

   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, 2014 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 #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 those tasks created with kthread.
  54  * Using these routines with threads not started via kthread will cause
  55  * panics because no task_struct is allocated and td_retval[1] is
  56  * overwritten by syscalls which kernel threads will not make use of.
  57  */
  58 struct task_struct {
  59         struct  thread *task_thread;
  60         int     (*task_fn)(void *data);
  61         void    *task_data;
  62         int     task_ret;
  63         int     state;
  64         int     should_stop;
  65 };
  66
  67 #define current                 task_struct_get(curthread)
  68 #define task_struct_get(x)      ((struct task_struct *)(uintptr_t)(x)->td_retval[1])
  69 #define task_struct_set(x, y)   (x)->td_retval[1] = (uintptr_t)(y)
  70
  71 /* ensure the task_struct pointer fits into the td_retval[1] field */
  72 CTASSERT(sizeof(((struct thread *)0)->td_retval[1]) >= sizeof(uintptr_t));
  73
  74 #define set_current_state(x)                                            \
  75         atomic_store_rel_int((volatile int *)&current->state, (x))
  76 #define __set_current_state(x)  current->state = (x)
  77
  78
  79 #define schedule()                                                      \
  80 do {                                                                    \
  81         void *c;                                                        \
  82                                                                         \
  83         if (cold)                                                       \
  84                 break;                                                  \
  85         c = curthread;                                                  \
  86         sleepq_lock(c);                                                 \
  87         if (current->state == TASK_INTERRUPTIBLE ||                     \
  88             current->state == TASK_UNINTERRUPTIBLE) {                   \
  89                 sleepq_add(c, NULL, "task", SLEEPQ_SLEEP, 0);           \
  90                 sleepq_wait(c, 0);                                      \
  91         } else {                                                        \
  92                 sleepq_release(c);                                      \
  93                 sched_relinquish(curthread);                            \
  94         }                                                               \
  95 } while (0)
  96
  97 #define wake_up_process(x)                                              \
  98 do {                                                                    \
  99         int wakeup_swapper;                                             \
 100         void *c;                                                        \
 101                                                                         \
 102         c = (x)->task_thread;                                           \
 103         sleepq_lock(c);                                                 \
 104         (x)->state = TASK_RUNNING;                                      \
 105         wakeup_swapper = sleepq_signal(c, SLEEPQ_SLEEP, 0, 0);          \
 106         sleepq_release(c);                                              \
 107         if (wakeup_swapper)                                             \
 108                 kick_proc0();                                           \
 109 } while (0)
 110
 111 #define cond_resched()  if (!cold)      sched_relinquish(curthread)
 112
 113 #define sched_yield()   sched_relinquish(curthread)
 114
 115 static inline long
 116 schedule_timeout(signed long timeout)
 117 {
 118         if (timeout < 0)
 119                 return 0;
 120
 121         pause("lstim", timeout);
 122
 123         return 0;
 124 }
 125
 126 #endif  /* _LINUX_SCHED_H_ */