include/asm-m68knommu/thread_info.h

   1 /* thread_info.h: m68knommu low-level thread information
   2  * adapted from the i386 and PPC versions by Greg Ungerer (gerg@snapgear.com)
   3  *
   4  * Copyright (C) 2002  David Howells (dhowells@redhat.com)
   5  * - Incorporating suggestions made by Linus Torvalds and Dave Miller
   6  */
   7
   8 #ifndef _ASM_THREAD_INFO_H
   9 #define _ASM_THREAD_INFO_H
  10
  11 #include <asm/page.h>
  12
  13 #ifdef __KERNEL__
  14
  15 #ifndef __ASSEMBLY__
  16
  17 /*
  18  * Size of kernel stack for each process. This must be a power of 2...
  19  */
  20 #ifdef CONFIG_4KSTACKS
  21 #define THREAD_SIZE_ORDER (0)
  22 #else
  23 #define THREAD_SIZE_ORDER (1)
  24 #endif
  25
  26 /*
  27  * for asm files, THREAD_SIZE is now generated by asm-offsets.c
  28  */
  29 #define THREAD_SIZE (PAGE_SIZE<<THREAD_SIZE_ORDER)
  30
  31 /*
  32  * low level task data.
  33  */
  34 struct thread_info {
  35         struct task_struct *task;               /* main task structure */
  36         struct exec_domain *exec_domain;        /* execution domain */
  37         unsigned long      flags;               /* low level flags */
  38         int                cpu;                 /* cpu we're on */
  39         int                preempt_count;       /* 0 => preemptable, <0 => BUG */
  40         struct restart_block restart_block;
  41 };
  42
  43 /*
  44  * macros/functions for gaining access to the thread information structure
  45  */
  46 #define INIT_THREAD_INFO(tsk)                   \
  47 {                                               \
  48         .task           = &tsk,                 \
  49         .exec_domain    = &default_exec_domain, \
  50         .flags          = 0,                    \
  51         .cpu            = 0,                    \
  52         .restart_block  = {                     \
  53                 .fn = do_no_restart_syscall,    \
  54         },                                      \
  55 }
  56
  57 #define init_thread_info        (init_thread_union.thread_info)
  58 #define init_stack              (init_thread_union.stack)
  59
  60
  61 /* how to get the thread information struct from C */
  62 static inline struct thread_info *current_thread_info(void)
  63 {
  64         struct thread_info *ti;
  65         __asm__(
  66                 "move.l %%sp, %0 \n\t"
  67                 "and.l  %1, %0"
  68                 : "=&d"(ti)
  69                 : "di" (~(THREAD_SIZE-1))
  70                 );
  71         return ti;
  72 }
  73
  74 /* thread information allocation */
  75 #define alloc_thread_info(tsk) ((struct thread_info *) \
  76                                 __get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER))
  77 #define free_thread_info(ti)    free_pages((unsigned long) (ti), THREAD_SIZE_ORDER)
  78 #endif /* __ASSEMBLY__ */
  79
  80 #define PREEMPT_ACTIVE  0x4000000
  81
  82 /*
  83  * thread information flag bit numbers
  84  */
  85 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
  86 #define TIF_SIGPENDING          1       /* signal pending */
  87 #define TIF_NEED_RESCHED        2       /* rescheduling necessary */
  88 #define TIF_POLLING_NRFLAG      3       /* true if poll_idle() is polling
  89                                            TIF_NEED_RESCHED */
  90 #define TIF_MEMDIE              4
  91
  92 /* as above, but as bit values */
  93 #define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
  94 #define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
  95 #define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
  96 #define _TIF_POLLING_NRFLAG     (1<<TIF_POLLING_NRFLAG)
  97
  98 #define _TIF_WORK_MASK          0x0000FFFE      /* work to do on interrupt/exception return */
  99
 100 #endif /* __KERNEL__ */
 101
 102 #endif /* _ASM_THREAD_INFO_H */