arch/blackfin/include/asm/thread_info.h

   1 /*
   2  * Copyright 2004-2009 Analog Devices Inc.
   3  *
   4  * Licensed under the GPL-2 or later.
   5  */
   6
   7 #ifndef _ASM_THREAD_INFO_H
   8 #define _ASM_THREAD_INFO_H
   9
  10 #include <asm/page.h>
  11 #include <asm/entry.h>
  12 #include <asm/l1layout.h>
  13 #include <linux/compiler.h>
  14
  15 #ifdef __KERNEL__
  16
  17 /* Thread Align Mask to reach to the top of the stack
  18  * for any process
  19  */
  20 #define ALIGN_PAGE_MASK         0xffffe000
  21
  22 /*
  23  * Size of kernel stack for each process. This must be a power of 2...
  24  */
  25 #define THREAD_SIZE_ORDER       1
  26 #define THREAD_SIZE             8192    /* 2 pages */
  27 #define STACK_WARN              (THREAD_SIZE/8)
  28
  29 #ifndef __ASSEMBLY__
  30
  31 typedef unsigned long mm_segment_t;
  32
  33 /*
  34  * low level task data.
  35  * If you change this, change the TI_* offsets below to match.
  36  */
  37
  38 struct thread_info {
  39         struct task_struct *task;       /* main task structure */
  40         struct exec_domain *exec_domain;        /* execution domain */
  41         unsigned long flags;    /* low level flags */
  42         int cpu;                /* cpu we're on */
  43         int preempt_count;      /* 0 => preemptable, <0 => BUG */
  44         mm_segment_t addr_limit;        /* address limit */
  45         struct restart_block restart_block;
  46 #ifndef CONFIG_SMP
  47         struct l1_scratch_task_info l1_task_info;
  48 #endif
  49 };
  50
  51 /*
  52  * macros/functions for gaining access to the thread information structure
  53  */
  54 #define INIT_THREAD_INFO(tsk)                   \
  55 {                                               \
  56         .task           = &tsk,                 \
  57         .exec_domain    = &default_exec_domain, \
  58         .flags          = 0,                    \
  59         .cpu            = 0,                    \
  60         .preempt_count  = INIT_PREEMPT_COUNT,   \
  61         .restart_block  = {                     \
  62                 .fn = do_no_restart_syscall,    \
  63         },                                      \
  64 }
  65 #define init_thread_info        (init_thread_union.thread_info)
  66 #define init_stack              (init_thread_union.stack)
  67
  68 /* Given a task stack pointer, you can find its corresponding
  69  * thread_info structure just by masking it to the THREAD_SIZE
  70  * boundary (currently 8K as you can see above).
  71  */
  72 __attribute_const__
  73 static inline struct thread_info *current_thread_info(void)
  74 {
  75         struct thread_info *ti;
  76       __asm__("%0 = sp;" : "=da"(ti) :
  77         );
  78         return (struct thread_info *)((long)ti & ~((long)THREAD_SIZE-1));
  79 }
  80
  81 #endif                          /* __ASSEMBLY__ */
  82
  83 /*
  84  * Offsets in thread_info structure, used in assembly code
  85  */
  86 #define TI_TASK         0
  87 #define TI_EXECDOMAIN   4
  88 #define TI_FLAGS        8
  89 #define TI_CPU          12
  90 #define TI_PREEMPT      16
  91
  92 #define PREEMPT_ACTIVE  0x4000000
  93
  94 /*
  95  * thread information flag bit numbers
  96  */
  97 #define TIF_SYSCALL_TRACE       0       /* syscall trace active */
  98 #define TIF_SIGPENDING          1       /* signal pending */
  99 #define TIF_NEED_RESCHED        2       /* rescheduling necessary */
 100 #define TIF_POLLING_NRFLAG      3       /* true if poll_idle() is polling
 101                                            TIF_NEED_RESCHED */
 102 #define TIF_MEMDIE              4
 103 #define TIF_RESTORE_SIGMASK     5       /* restore signal mask in do_signal() */
 104 #define TIF_FREEZE              6       /* is freezing for suspend */
 105 #define TIF_IRQ_SYNC            7       /* sync pipeline stage */
 106
 107 /* as above, but as bit values */
 108 #define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
 109 #define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
 110 #define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
 111 #define _TIF_POLLING_NRFLAG     (1<<TIF_POLLING_NRFLAG)
 112 #define _TIF_RESTORE_SIGMASK    (1<<TIF_RESTORE_SIGMASK)
 113 #define _TIF_FREEZE             (1<<TIF_FREEZE)
 114 #define _TIF_IRQ_SYNC           (1<<TIF_IRQ_SYNC)
 115
 116 #define _TIF_WORK_MASK          0x0000FFFE      /* work to do on interrupt/exception return */
 117
 118 #endif                          /* __KERNEL__ */
 119
 120 #endif                          /* _ASM_THREAD_INFO_H */