arch/arc/include/asm/thread_info.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
   4  *
   5  * Vineetg: Oct 2009
   6  *  No need for ARC specific thread_info allocator (kmalloc/free). This is
   7  *  anyways one page allocation, thus slab alloc can be short-circuited and
   8  *  the generic version (get_free_page) would be loads better.
   9  *
  10  * Sameer Dhavale: Codito Technologies 2004
  11  */
  12
  13 #ifndef _ASM_THREAD_INFO_H
  14 #define _ASM_THREAD_INFO_H
  15
  16 #include <asm/page.h>
  17
  18 #ifdef CONFIG_16KSTACKS
  19 #define THREAD_SIZE_ORDER 1
  20 #else
  21 #define THREAD_SIZE_ORDER 0
  22 #endif
  23
  24 #define THREAD_SIZE     (PAGE_SIZE << THREAD_SIZE_ORDER)
  25 #define THREAD_SHIFT    (PAGE_SHIFT << THREAD_SIZE_ORDER)
  26
  27 #ifndef __ASSEMBLY__
  28
  29 #include <linux/thread_info.h>
  30 #include <asm/segment.h>
  31
  32 /*
  33  * low level task data that entry.S needs immediate access to
  34  * - this struct should fit entirely inside of one cache line
  35  * - this struct shares the supervisor stack pages
  36  * - if the contents of this structure are changed, the assembly constants
  37  *   must also be changed
  38  */
  39 struct thread_info {
  40         unsigned long flags;            /* low level flags */
  41         int preempt_count;              /* 0 => preemptable, <0 => BUG */
  42         struct task_struct *task;       /* main task structure */
  43         mm_segment_t addr_limit;        /* thread address space */
  44         __u32 cpu;                      /* current CPU */
  45         unsigned long thr_ptr;          /* TLS ptr */
  46 };
  47
  48 /*
  49  * macros/functions for gaining access to the thread information structure
  50  *
  51  * preempt_count needs to be 1 initially, until the scheduler is functional.
  52  */
  53 #define INIT_THREAD_INFO(tsk)                   \
  54 {                                               \
  55         .task       = &tsk,                     \
  56         .flags      = 0,                        \
  57         .cpu        = 0,                        \
  58         .preempt_count  = INIT_PREEMPT_COUNT,   \
  59         .addr_limit = KERNEL_DS,                \
  60 }
  61
  62 static inline __attribute_const__ struct thread_info *current_thread_info(void)
  63 {
  64         register unsigned long sp asm("sp");
  65         return (struct thread_info *)(sp & ~(THREAD_SIZE - 1));
  66 }
  67
  68 #endif /* !__ASSEMBLY__ */
  69
  70 /*
  71  * thread information flags
  72  * - these are process state flags that various assembly files may need to
  73  *   access
  74  * - pending work-to-be-done flags are in LSW
  75  * - other flags in MSW
  76  */
  77 #define TIF_RESTORE_SIGMASK     0       /* restore sig mask in do_signal() */
  78 #define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
  79 #define TIF_SIGPENDING          2       /* signal pending */
  80 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
  81 #define TIF_SYSCALL_AUDIT       4       /* syscall auditing active */
  82 #define TIF_SYSCALL_TRACE       15      /* syscall trace active */
  83
  84 /* true if poll_idle() is polling TIF_NEED_RESCHED */
  85 #define TIF_MEMDIE              16
  86
  87 #define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
  88 #define _TIF_NOTIFY_RESUME      (1<<TIF_NOTIFY_RESUME)
  89 #define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
  90 #define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
  91 #define _TIF_SYSCALL_AUDIT      (1<<TIF_SYSCALL_AUDIT)
  92 #define _TIF_MEMDIE             (1<<TIF_MEMDIE)
  93
  94 /* work to do on interrupt/exception return */
  95 #define _TIF_WORK_MASK          (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
  96                                  _TIF_NOTIFY_RESUME)
  97
  98 /*
  99  * _TIF_ALLWORK_MASK includes SYSCALL_TRACE, but we don't need it.
 100  * SYSCALL_TRACE is anyway seperately/unconditionally tested right after a
 101  * syscall, so all that reamins to be tested is _TIF_WORK_MASK
 102  */
 103
 104 #endif /* _ASM_THREAD_INFO_H */