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#include <linux/stringify.h>
  15#include <asm/kmem_layout.h>
  16
  17#define CURRENT_SHIFT KERNEL_STACK_SHIFT
  18
  19#ifndef __ASSEMBLY__
  20# include <asm/processor.h>
  21#endif
  22
  23/*
  24 * low level task data that entry.S needs immediate access to
  25 * - this struct should fit entirely inside of one cache line
  26 * - this struct shares the supervisor stack pages
  27 * - if the contents of this structure are changed, the assembly constants
  28 *   must also be changed
  29 */
  30
  31#ifndef __ASSEMBLY__
  32
  33#if XTENSA_HAVE_COPROCESSORS
  34
  35typedef struct xtregs_coprocessor {
  36        xtregs_cp0_t cp0;
  37        xtregs_cp1_t cp1;
  38        xtregs_cp2_t cp2;
  39        xtregs_cp3_t cp3;
  40        xtregs_cp4_t cp4;
  41        xtregs_cp5_t cp5;
  42        xtregs_cp6_t cp6;
  43        xtregs_cp7_t cp7;
  44} xtregs_coprocessor_t;
  45
  46#endif
  47
  48struct thread_info {
  49        struct task_struct      *task;          /* main task structure */
  50        unsigned long           flags;          /* low level flags */
  51        unsigned long           status;         /* thread-synchronous flags */
  52        __u32                   cpu;            /* current CPU */
  53        __s32                   preempt_count;  /* 0 => preemptable,< 0 => BUG*/
  54
  55        mm_segment_t            addr_limit;     /* thread address space */
  56
  57        unsigned long           cpenable;
  58
  59        /* Allocate storage for extra user states and coprocessor states. */
  60#if XTENSA_HAVE_COPROCESSORS
  61        xtregs_coprocessor_t    xtregs_cp;
  62#endif
  63        xtregs_user_t           xtregs_user;
  64};
  65
  66#endif
  67
  68/*
  69 * macros/functions for gaining access to the thread information structure
  70 */
  71
  72#ifndef __ASSEMBLY__
  73
  74#define INIT_THREAD_INFO(tsk)                   \
  75{                                               \
  76        .task           = &tsk,                 \
  77        .flags          = 0,                    \
  78        .cpu            = 0,                    \
  79        .preempt_count  = INIT_PREEMPT_COUNT,   \
  80        .addr_limit     = KERNEL_DS,            \
  81}
  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, "__stringify(CURRENT_SHIFT)"\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, CURRENT_SHIFT; \
  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 */
 105#define TIF_SYSCALL_TRACE       0       /* syscall trace active */
 106#define TIF_SIGPENDING          1       /* signal pending */
 107#define TIF_NEED_RESCHED        2       /* rescheduling necessary */
 108#define TIF_SINGLESTEP          3       /* restore singlestep on return to user mode */
 109#define TIF_SYSCALL_TRACEPOINT  4       /* syscall tracepoint instrumentation */
 110#define TIF_MEMDIE              5       /* is terminating due to OOM killer */
 111#define TIF_RESTORE_SIGMASK     6       /* restore signal mask in do_signal() */
 112#define TIF_NOTIFY_RESUME       7       /* callback before returning to user */
 113#define TIF_DB_DISABLED         8       /* debug trap disabled for syscall */
 114
 115#define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
 116#define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
 117#define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
 118#define _TIF_SINGLESTEP         (1<<TIF_SINGLESTEP)
 119#define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
 120
 121#define _TIF_WORK_MASK          (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
 122                                 _TIF_SYSCALL_TRACEPOINT)
 123
 124#define THREAD_SIZE KERNEL_STACK_SIZE
 125#define THREAD_SIZE_ORDER (KERNEL_STACK_SHIFT - PAGE_SHIFT)
 126
 127#endif  /* _XTENSA_THREAD_INFO */
 128