LXR linux/arch/xtensa/include/asm/thread

   1/*
   2 * include/asm-xtensa/thread_info.h
   3 *
   4 * This file is subject to the terms and conditions of the GNU General Public
   5 * License.  See the file "COPYING" in the main directory of this archive
   6 * for more details.
   7 *
   8 * Copyright (C) 2001 - 2005 Tensilica Inc.
   9 */
  10
  11#ifndef _XTENSA_THREAD_INFO_H
  12#define _XTENSA_THREAD_INFO_H
  13
  14#ifdef __KERNEL__
  15
  16#ifndef __ASSEMBLY__
  17# include <asm/processor.h>
  18#endif
  19
  20/*
  21 * low level task data that entry.S needs immediate access to
  22 * - this struct should fit entirely inside of one cache line
  23 * - this struct shares the supervisor stack pages
  24 * - if the contents of this structure are changed, the assembly constants
  25 *   must also be changed
  26 */
  27
  28#ifndef __ASSEMBLY__
  29
  30#if XTENSA_HAVE_COPROCESSORS
  31
  32typedef struct xtregs_coprocessor {
  33        xtregs_cp0_t cp0;
  34        xtregs_cp1_t cp1;
  35        xtregs_cp2_t cp2;
  36        xtregs_cp3_t cp3;
  37        xtregs_cp4_t cp4;
  38        xtregs_cp5_t cp5;
  39        xtregs_cp6_t cp6;
  40        xtregs_cp7_t cp7;
  41} xtregs_coprocessor_t;
  42
  43#endif
  44
  45struct thread_info {
  46        struct task_struct      *task;          /* main task structure */
  47        unsigned long           flags;          /* low level flags */
  48        unsigned long           status;         /* thread-synchronous flags */
  49        __u32                   cpu;            /* current CPU */
  50        __s32                   preempt_count;  /* 0 => preemptable,< 0 => BUG*/
  51
  52        mm_segment_t            addr_limit;     /* thread address space */
  53
  54        unsigned long           cpenable;
  55
  56        /* Allocate storage for extra user states and coprocessor states. */
  57#if XTENSA_HAVE_COPROCESSORS
  58        xtregs_coprocessor_t    xtregs_cp;
  59#endif
  60        xtregs_user_t           xtregs_user;
  61};
  62
  63#endif
  64
  65/*
  66 * macros/functions for gaining access to the thread information structure
  67 */
  68
  69#ifndef __ASSEMBLY__
  70
  71#define INIT_THREAD_INFO(tsk)                   \
  72{                                               \
  73        .task           = &tsk,                 \
  74        .flags          = 0,                    \
  75        .cpu            = 0,                    \
  76        .preempt_count  = INIT_PREEMPT_COUNT,   \
  77        .addr_limit     = KERNEL_DS,            \
  78}
  79
  80#define init_thread_info        (init_thread_union.thread_info)
  81#define init_stack              (init_thread_union.stack)
  82
  83/* how to get the thread information struct from C */
  84static inline struct thread_info *current_thread_info(void)
  85{
  86        struct thread_info *ti;
  87         __asm__("extui %0,a1,0,13\n\t"
  88                 "xor %0, a1, %0" : "=&r" (ti) : );
  89        return ti;
  90}
  91
  92#else /* !__ASSEMBLY__ */
  93
  94/* how to get the thread information struct from ASM */
  95#define GET_THREAD_INFO(reg,sp) \
  96        extui reg, sp, 0, 13; \
  97        xor   reg, sp, reg
  98#endif
  99
 100
 101/*
 102 * thread information flags
 103 * - these are process state flags that various assembly files may need to access
 104 * - pending work-to-be-done flags are in LSW
 105 * - other flags in MSW
 106 */
 107#define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 108#define TIF_SIGPENDING          1       /* signal pending */
 109#define TIF_NEED_RESCHED        2       /* rescheduling necessary */
 110#define TIF_SINGLESTEP          3       /* restore singlestep on return to user mode */
 111#define TIF_MEMDIE              5       /* is terminating due to OOM killer */
 112#define TIF_RESTORE_SIGMASK     6       /* restore signal mask in do_signal() */
 113#define TIF_NOTIFY_RESUME       7       /* callback before returning to user */
 114#define TIF_DB_DISABLED         8       /* debug trap disabled for syscall */
 115
 116#define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
 117#define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
 118#define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
 119#define _TIF_SINGLESTEP         (1<<TIF_SINGLESTEP)
 120
 121#define _TIF_WORK_MASK          0x0000FFFE      /* work to do on interrupt/exception return */
 122#define _TIF_ALLWORK_MASK       0x0000FFFF      /* work to do on any return to u-space */
 123
 124/*
 125 * Thread-synchronous status.
 126 *
 127 * This is different from the flags in that nobody else
 128 * ever touches our thread-synchronous status, so we don't
 129 * have to worry about atomic accesses.
 130 */
 131#define TS_USEDFPU              0x0001  /* FPU was used by this task this quantum (SMP) */
 132
 133#define THREAD_SIZE 8192        //(2*PAGE_SIZE)
 134#define THREAD_SIZE_ORDER 1
 135
 136#endif  /* __KERNEL__ */
 137#endif  /* _XTENSA_THREAD_INFO */
 138