LXR linux/arch/tile/include/asm/thread

   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 */
  27struct 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
  86void arch_release_thread_info(struct thread_info *info);
  87
  88/* How to get the thread information struct from C. */
  89register 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. */
  95extern void smp_nap(void);
  96
  97/* Enable interrupts racelessly and nap forever: helper for cpu_idle(). */
  98extern 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
 170static 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}
 176static inline void clear_restore_sigmask(void)
 177{
 178        current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
 179}
 180static inline bool test_restore_sigmask(void)
 181{
 182        return current_thread_info()->status & TS_RESTORE_SIGMASK;
 183}
 184static 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 */
 195