arch/tile/include/asm/thread_info.h

   1 /*
   2  * Copyright (C) 2002  David Howells (dhowells@redhat.com)
   3  * Copyright 2010 Tilera Corporation. All Rights Reserved.
   4  *
   5  *   This program is free software; you can redistribute it and/or
   6  *   modify it under the terms of the GNU General Public License
   7  *   as published by the Free Software Foundation, version 2.
   8  *
   9  *   This program is distributed in the hope that it will be useful, but
  10  *   WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  12  *   NON INFRINGEMENT.  See the GNU General Public License for
  13  *   more details.
  14  */
  15
  16 #ifndef _ASM_TILE_THREAD_INFO_H
  17 #define _ASM_TILE_THREAD_INFO_H
  18
  19 #include <asm/processor.h>
  20 #include <asm/page.h>
  21 #ifndef __ASSEMBLY__
  22
  23 /*
  24  * Low level task data that assembly code needs immediate access to.
  25  * The structure is placed at the bottom of the supervisor stack.
  26  */
  27 struct thread_info {
  28         struct task_struct      *task;          /* main task structure */
  29         struct exec_domain      *exec_domain;   /* execution domain */
  30         unsigned long           flags;          /* low level flags */
  31         unsigned long           status;         /* thread-synchronous flags */
  32         __u32                   homecache_cpu;  /* CPU we are homecached on */
  33         __u32                   cpu;            /* current CPU */
  34         int                     preempt_count;  /* 0 => preemptable,
  35                                                    <0 => BUG */
  36
  37         mm_segment_t            addr_limit;     /* thread address space
  38                                                    (KERNEL_DS or USER_DS) */
  39         struct restart_block    restart_block;
  40         struct single_step_state *step_state;   /* single step state
  41                                                    (if non-zero) */
  42         int                     align_ctl;      /* controls unaligned access */
  43 #ifdef __tilegx__
  44         unsigned long           unalign_jit_tmp[4]; /* temp r0..r3 storage */
  45         void __user             *unalign_jit_base; /* unalign fixup JIT base */
  46 #endif
  47 };
  48
  49 /*
  50  * macros/functions for gaining access to the thread information structure.
  51  */
  52 #define INIT_THREAD_INFO(tsk)                   \
  53 {                                               \
  54         .task           = &tsk,                 \
  55         .exec_domain    = &default_exec_domain, \
  56         .flags          = 0,                    \
  57         .cpu            = 0,                    \
  58         .preempt_count  = INIT_PREEMPT_COUNT,   \
  59         .addr_limit     = KERNEL_DS,            \
  60         .restart_block  = {                     \
  61                 .fn = do_no_restart_syscall,    \
  62         },                                      \
  63         .step_state     = NULL,                 \
  64         .align_ctl      = 0,                    \
  65 }
  66
  67 #define init_thread_info        (init_thread_union.thread_info)
  68 #define init_stack              (init_thread_union.stack)
  69
  70 #endif /* !__ASSEMBLY__ */
  71
  72 #if PAGE_SIZE < 8192
  73 #define THREAD_SIZE_ORDER (13 - PAGE_SHIFT)
  74 #else
  75 #define THREAD_SIZE_ORDER (0)
  76 #endif
  77 #define THREAD_SIZE_PAGES (1 << THREAD_SIZE_ORDER)
  78
  79 #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
  80 #define LOG2_THREAD_SIZE (PAGE_SHIFT + THREAD_SIZE_ORDER)
  81
  82 #define STACK_WARN             (THREAD_SIZE/8)
  83
  84 #ifndef __ASSEMBLY__
  85
  86 void arch_release_thread_info(struct thread_info *info);
  87
  88 /* How to get the thread information struct from C. */
  89 register unsigned long stack_pointer __asm__("sp");
  90
  91 #define current_thread_info() \
  92   ((struct thread_info *)(stack_pointer & -THREAD_SIZE))
  93
  94 /* Sit on a nap instruction until interrupted. */
  95 extern void smp_nap(void);
  96
  97 /* Enable interrupts racelessly and nap forever: helper for cpu_idle(). */
  98 extern void _cpu_idle(void);
  99
 100 #else /* __ASSEMBLY__ */
 101
 102 /*
 103  * How to get the thread information struct from assembly.
 104  * Note that we use different macros since different architectures
 105  * have different semantics in their "mm" instruction and we would
 106  * like to guarantee that the macro expands to exactly one instruction.
 107  */
 108 #ifdef __tilegx__
 109 #define EXTRACT_THREAD_INFO(reg) mm reg, zero, LOG2_THREAD_SIZE, 63
 110 #else
 111 #define GET_THREAD_INFO(reg) mm reg, sp, zero, LOG2_THREAD_SIZE, 31
 112 #endif
 113
 114 #endif /* !__ASSEMBLY__ */
 115
 116 /*
 117  * Thread information flags that various assembly files may need to access.
 118  * Keep flags accessed frequently in low bits, particular since it makes
 119  * it easier to build constants in assembly.
 120  */
 121 #define TIF_SIGPENDING          0       /* signal pending */
 122 #define TIF_NEED_RESCHED        1       /* rescheduling necessary */
 123 #define TIF_SINGLESTEP          2       /* restore singlestep on return to
 124                                            user mode */
 125 #define TIF_ASYNC_TLB           3       /* got an async TLB fault in kernel */
 126 #define TIF_SYSCALL_TRACE       4       /* syscall trace active */
 127 #define TIF_SYSCALL_AUDIT       5       /* syscall auditing active */
 128 #define TIF_SECCOMP             6       /* secure computing */
 129 #define TIF_MEMDIE              7       /* OOM killer at work */
 130 #define TIF_NOTIFY_RESUME       8       /* callback before returning to user */
 131 #define TIF_SYSCALL_TRACEPOINT  9       /* syscall tracepoint instrumentation */
 132
 133 #define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
 134 #define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
 135 #define _TIF_SINGLESTEP         (1<<TIF_SINGLESTEP)
 136 #define _TIF_ASYNC_TLB          (1<<TIF_ASYNC_TLB)
 137 #define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
 138 #define _TIF_SYSCALL_AUDIT      (1<<TIF_SYSCALL_AUDIT)
 139 #define _TIF_SECCOMP            (1<<TIF_SECCOMP)
 140 #define _TIF_MEMDIE             (1<<TIF_MEMDIE)
 141 #define _TIF_NOTIFY_RESUME      (1<<TIF_NOTIFY_RESUME)
 142 #define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
 143
 144 /* Work to do on any return to user space. */
 145 #define _TIF_ALLWORK_MASK \
 146   (_TIF_SIGPENDING|_TIF_NEED_RESCHED|_TIF_SINGLESTEP|\
 147    _TIF_ASYNC_TLB|_TIF_NOTIFY_RESUME)
 148
 149 /* Work to do at syscall entry. */
 150 #define _TIF_SYSCALL_ENTRY_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT)
 151
 152 /* Work to do at syscall exit. */
 153 #define _TIF_SYSCALL_EXIT_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT)
 154
 155 /*
 156  * Thread-synchronous status.
 157  *
 158  * This is different from the flags in that nobody else
 159  * ever touches our thread-synchronous status, so we don't
 160  * have to worry about atomic accesses.
 161  */
 162 #ifdef __tilegx__
 163 #define TS_COMPAT               0x0001  /* 32-bit compatibility mode */
 164 #endif
 165 #define TS_POLLING              0x0004  /* in idle loop but not sleeping */
 166 #define TS_RESTORE_SIGMASK      0x0008  /* restore signal mask in do_signal */
 167
 168 #ifndef __ASSEMBLY__
 169 #define HAVE_SET_RESTORE_SIGMASK        1
 170 static inline void set_restore_sigmask(void)
 171 {
 172         struct thread_info *ti = current_thread_info();
 173         ti->status |= TS_RESTORE_SIGMASK;
 174         WARN_ON(!test_bit(TIF_SIGPENDING, &ti->flags));
 175 }
 176 static inline void clear_restore_sigmask(void)
 177 {
 178         current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
 179 }
 180 static inline bool test_restore_sigmask(void)
 181 {
 182         return current_thread_info()->status & TS_RESTORE_SIGMASK;
 183 }
 184 static inline bool test_and_clear_restore_sigmask(void)
 185 {
 186         struct thread_info *ti = current_thread_info();
 187         if (!(ti->status & TS_RESTORE_SIGMASK))
 188                 return false;
 189         ti->status &= ~TS_RESTORE_SIGMASK;
 190         return true;
 191 }
 192 #endif  /* !__ASSEMBLY__ */
 193
 194 #endif /* _ASM_TILE_THREAD_INFO_H */