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         unsigned long           flags;          /* low level flags */
  30         unsigned long           status;         /* thread-synchronous flags */
  31         __u32                   homecache_cpu;  /* CPU we are homecached on */
  32         __u32                   cpu;            /* current CPU */
  33         int                     preempt_count;  /* 0 => preemptable,
  34                                                    <0 => BUG */
  35
  36         mm_segment_t            addr_limit;     /* thread address space
  37                                                    (KERNEL_DS or USER_DS) */
  38         struct single_step_state *step_state;   /* single step state
  39                                                    (if non-zero) */
  40         int                     align_ctl;      /* controls unaligned access */
  41 #ifdef __tilegx__
  42         unsigned long           unalign_jit_tmp[4]; /* temp r0..r3 storage */
  43         void __user             *unalign_jit_base; /* unalign fixup JIT base */
  44 #endif
  45         bool in_backtrace;                      /* currently doing backtrace? */
  46 };
  47
  48 /*
  49  * macros/functions for gaining access to the thread information structure.
  50  */
  51 #define INIT_THREAD_INFO(tsk)                   \
  52 {                                               \
  53         .task           = &tsk,                 \
  54         .flags          = 0,                    \
  55         .cpu            = 0,                    \
  56         .preempt_count  = INIT_PREEMPT_COUNT,   \
  57         .addr_limit     = KERNEL_DS,            \
  58         .step_state     = NULL,                 \
  59         .align_ctl      = 0,                    \
  60 }
  61
  62 #define init_thread_info        (init_thread_union.thread_info)
  63 #define init_stack              (init_thread_union.stack)
  64
  65 #endif /* !__ASSEMBLY__ */
  66
  67 #if PAGE_SIZE < 8192
  68 #define THREAD_SIZE_ORDER (13 - PAGE_SHIFT)
  69 #else
  70 #define THREAD_SIZE_ORDER (0)
  71 #endif
  72 #define THREAD_SIZE_PAGES (1 << THREAD_SIZE_ORDER)
  73
  74 #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
  75 #define LOG2_THREAD_SIZE (PAGE_SHIFT + THREAD_SIZE_ORDER)
  76
  77 #define STACK_WARN             (THREAD_SIZE/8)
  78
  79 #ifndef __ASSEMBLY__
  80
  81 void arch_release_thread_stack(unsigned long *stack);
  82
  83 /* How to get the thread information struct from C. */
  84 register unsigned long stack_pointer __asm__("sp");
  85
  86 #define current_thread_info() \
  87   ((struct thread_info *)(stack_pointer & -THREAD_SIZE))
  88
  89 /* Sit on a nap instruction until interrupted. */
  90 extern void smp_nap(void);
  91
  92 /* Enable interrupts racelessly and nap forever: helper for arch_cpu_idle(). */
  93 extern void _cpu_idle(void);
  94
  95 #else /* __ASSEMBLY__ */
  96
  97 /*
  98  * How to get the thread information struct from assembly.
  99  * Note that we use different macros since different architectures
 100  * have different semantics in their "mm" instruction and we would
 101  * like to guarantee that the macro expands to exactly one instruction.
 102  */
 103 #ifdef __tilegx__
 104 #define EXTRACT_THREAD_INFO(reg) mm reg, zero, LOG2_THREAD_SIZE, 63
 105 #else
 106 #define GET_THREAD_INFO(reg) mm reg, sp, zero, LOG2_THREAD_SIZE, 31
 107 #endif
 108
 109 #endif /* !__ASSEMBLY__ */
 110
 111 /*
 112  * Thread information flags that various assembly files may need to access.
 113  * Keep flags accessed frequently in low bits, particular since it makes
 114  * it easier to build constants in assembly.
 115  */
 116 #define TIF_SIGPENDING          0       /* signal pending */
 117 #define TIF_NEED_RESCHED        1       /* rescheduling necessary */
 118 #define TIF_SINGLESTEP          2       /* restore singlestep on return to
 119                                            user mode */
 120 #define TIF_ASYNC_TLB           3       /* got an async TLB fault in kernel */
 121 #define TIF_SYSCALL_TRACE       4       /* syscall trace active */
 122 #define TIF_SYSCALL_AUDIT       5       /* syscall auditing active */
 123 #define TIF_SECCOMP             6       /* secure computing */
 124 #define TIF_MEMDIE              7       /* OOM killer at work */
 125 #define TIF_NOTIFY_RESUME       8       /* callback before returning to user */
 126 #define TIF_SYSCALL_TRACEPOINT  9       /* syscall tracepoint instrumentation */
 127 #define TIF_POLLING_NRFLAG      10      /* idle is polling for TIF_NEED_RESCHED */
 128 #define TIF_NOHZ                11      /* in adaptive nohz mode */
 129
 130 #define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
 131 #define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
 132 #define _TIF_SINGLESTEP         (1<<TIF_SINGLESTEP)
 133 #define _TIF_ASYNC_TLB          (1<<TIF_ASYNC_TLB)
 134 #define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
 135 #define _TIF_SYSCALL_AUDIT      (1<<TIF_SYSCALL_AUDIT)
 136 #define _TIF_SECCOMP            (1<<TIF_SECCOMP)
 137 #define _TIF_MEMDIE             (1<<TIF_MEMDIE)
 138 #define _TIF_NOTIFY_RESUME      (1<<TIF_NOTIFY_RESUME)
 139 #define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
 140 #define _TIF_POLLING_NRFLAG     (1<<TIF_POLLING_NRFLAG)
 141 #define _TIF_NOHZ               (1<<TIF_NOHZ)
 142
 143 /* Work to do as we loop to exit to user space. */
 144 #define _TIF_WORK_MASK \
 145         (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
 146          _TIF_ASYNC_TLB | _TIF_NOTIFY_RESUME)
 147
 148 /* Work to do on any return to user space. */
 149 #define _TIF_ALLWORK_MASK \
 150         (_TIF_WORK_MASK | _TIF_SINGLESTEP | _TIF_NOHZ)
 151
 152 /* Work to do at syscall entry. */
 153 #define _TIF_SYSCALL_ENTRY_WORK \
 154         (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_NOHZ)
 155
 156 /* Work to do at syscall exit. */
 157 #define _TIF_SYSCALL_EXIT_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT)
 158
 159 /*
 160  * Thread-synchronous status.
 161  *
 162  * This is different from the flags in that nobody else
 163  * ever touches our thread-synchronous status, so we don't
 164  * have to worry about atomic accesses.
 165  */
 166 #ifdef __tilegx__
 167 #define TS_COMPAT               0x0001  /* 32-bit compatibility mode */
 168 #endif
 169 #define TS_RESTORE_SIGMASK      0x0008  /* restore signal mask in do_signal */
 170
 171 #ifndef __ASSEMBLY__
 172 #define HAVE_SET_RESTORE_SIGMASK        1
 173 static inline void set_restore_sigmask(void)
 174 {
 175         struct thread_info *ti = current_thread_info();
 176         ti->status |= TS_RESTORE_SIGMASK;
 177         WARN_ON(!test_bit(TIF_SIGPENDING, &ti->flags));
 178 }
 179 static inline void clear_restore_sigmask(void)
 180 {
 181         current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
 182 }
 183 static inline bool test_restore_sigmask(void)
 184 {
 185         return current_thread_info()->status & TS_RESTORE_SIGMASK;
 186 }
 187 static inline bool test_and_clear_restore_sigmask(void)
 188 {
 189         struct thread_info *ti = current_thread_info();
 190         if (!(ti->status & TS_RESTORE_SIGMASK))
 191                 return false;
 192         ti->status &= ~TS_RESTORE_SIGMASK;
 193         return true;
 194 }
 195 #endif  /* !__ASSEMBLY__ */
 196
 197 #endif /* _ASM_TILE_THREAD_INFO_H */