include/asm-mips/thread_info.h

   1 /* thread_info.h: i386 low-level thread information
   2  *
   3  * Copyright (C) 2002  David Howells (dhowells@redhat.com)
   4  * - Incorporating suggestions made by Linus Torvalds and Dave Miller
   5  */
   6
   7 #ifndef _ASM_THREAD_INFO_H
   8 #define _ASM_THREAD_INFO_H
   9
  10 #ifdef __KERNEL__
  11
  12 #ifndef __ASSEMBLY__
  13
  14 #include <asm/processor.h>
  15
  16 /*
  17  * low level task data that entry.S needs immediate access to
  18  * - this struct should fit entirely inside of one cache line
  19  * - this struct shares the supervisor stack pages
  20  * - if the contents of this structure are changed, the assembly constants
  21  *   must also be changed
  22  */
  23 struct thread_info {
  24         struct task_struct      *task;          /* main task structure */
  25         struct exec_domain      *exec_domain;   /* execution domain */
  26         unsigned long           flags;          /* low level flags */
  27         __u32                   cpu;            /* current CPU */
  28         __s32                   preempt_count; /* 0 => preemptable, <0 => BUG */
  29
  30         mm_segment_t            addr_limit;     /* thread address space:
  31                                                    0-0xBFFFFFFF for user-thead
  32                                                    0-0xFFFFFFFF for kernel-thread
  33                                                 */
  34         struct restart_block    restart_block;
  35 };
  36
  37 #define PREEMPT_ACTIVE          0x4000000
  38
  39 /*
  40  * macros/functions for gaining access to the thread information structure
  41  *
  42  * preempt_count needs to be 1 initially, until the scheduler is functional.
  43  */
  44 #define INIT_THREAD_INFO(tsk)                   \
  45 {                                               \
  46         .task           = &tsk,                 \
  47         .exec_domain    = &default_exec_domain, \
  48         .flags          = 0,                    \
  49         .cpu            = 0,                    \
  50         .preempt_count  = 1,                    \
  51         .addr_limit     = KERNEL_DS,            \
  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 /* How to get the thread information struct from C.  */
  61 register struct thread_info *__current_thread_info __asm__("$28");
  62 #define current_thread_info()  __current_thread_info
  63
  64 /* thread information allocation */
  65 #define THREAD_SIZE_ORDER (1)
  66 #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
  67 #define alloc_thread_info(tsk) ((struct thread_info *) \
  68         __get_free_pages(GFP_KERNEL,THREAD_SIZE_ORDER))
  69 #define free_thread_info(ti) free_pages((unsigned long) (ti), THREAD_SIZE_ORDER)
  70 #define get_thread_info(ti) get_task_struct((ti)->task)
  71 #define put_thread_info(ti) put_task_struct((ti)->task)
  72
  73 #endif /* !__ASSEMBLY__ */
  74
  75 /*
  76  * thread information flags
  77  * - these are process state flags that various assembly files may need to
  78  *   access
  79  * - pending work-to-be-done flags are in LSW
  80  * - other flags in MSW
  81  */
  82 #define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
  83 #define TIF_SIGPENDING          2       /* signal pending */
  84 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
  85 #define TIF_USEDFPU             16      /* FPU was used by this task this quantum (SMP) */
  86 #define TIF_POLLING_NRFLAG      17      /* true if poll_idle() is polling TIF_NEED_RESCHED */
  87 #define TIF_SYSCALL_TRACE       31      /* syscall trace active */
  88
  89 #define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
  90 #define _TIF_NOTIFY_RESUME      (1<<TIF_NOTIFY_RESUME)
  91 #define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
  92 #define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
  93 #define _TIF_USEDFPU            (1<<TIF_USEDFPU)
  94 #define _TIF_POLLING_NRFLAG     (1<<TIF_POLLING_NRFLAG)
  95
  96 #define _TIF_WORK_MASK          0x0000fffe      /* work to do on
  97                                                    interrupt/exception return */
  98 #define _TIF_ALLWORK_MASK       0x8000fffe      /* work to do on any return to
  99                                                    u-space */
 100
 101 #endif /* __KERNEL__ */
 102
 103 #endif /* _ASM_THREAD_INFO_H */