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thread_info.h
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1 /* thread_info.h: MIPS low-level thread information
2  *
3  * Copyright (C) 2002 David Howells ([email protected])
4  * - Incorporating suggestions made by Linus Torvalds and Dave Miller
5  */
6 
7 #ifndef _ASM_THREAD_INFO_H
8 #define _ASM_THREAD_INFO_H
9 
10 #ifdef __KERNEL__
11 
12 
13 #ifndef __ASSEMBLY__
14 
15 #include <asm/processor.h>
16 
17 /*
18  * low level task data that entry.S needs immediate access to
19  * - this struct should fit entirely inside of one cache line
20  * - this struct shares the supervisor stack pages
21  * - if the contents of this structure are changed, the assembly constants
22  * must also be changed
23  */
24 struct thread_info {
25  struct task_struct *task; /* main task structure */
26  struct exec_domain *exec_domain; /* execution domain */
27  unsigned long flags; /* low level flags */
28  unsigned long tp_value; /* thread pointer */
29  __u32 cpu; /* current CPU */
30  int preempt_count; /* 0 => preemptable, <0 => BUG */
31 
32  mm_segment_t addr_limit; /* thread address space:
33  0-0xBFFFFFFF for user-thead
34  0-0xFFFFFFFF for kernel-thread
35  */
37  struct pt_regs *regs;
38 };
39 
40 /*
41  * macros/functions for gaining access to the thread information structure
42  */
43 #define INIT_THREAD_INFO(tsk) \
44 { \
45  .task = &tsk, \
46  .exec_domain = &default_exec_domain, \
47  .flags = _TIF_FIXADE, \
48  .cpu = 0, \
49  .preempt_count = INIT_PREEMPT_COUNT, \
50  .addr_limit = KERNEL_DS, \
51  .restart_block = { \
52  .fn = do_no_restart_syscall, \
53  }, \
54 }
55 
56 #define init_thread_info (init_thread_union.thread_info)
57 #define init_stack (init_thread_union.stack)
58 
59 /* How to get the thread information struct from C. */
60 register struct thread_info *__current_thread_info __asm__("$28");
61 #define current_thread_info() __current_thread_info
62 
63 #endif /* !__ASSEMBLY__ */
64 
65 /* thread information allocation */
66 #if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_32BIT)
67 #define THREAD_SIZE_ORDER (1)
68 #endif
69 #if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_64BIT)
70 #define THREAD_SIZE_ORDER (2)
71 #endif
72 #ifdef CONFIG_PAGE_SIZE_8KB
73 #define THREAD_SIZE_ORDER (1)
74 #endif
75 #ifdef CONFIG_PAGE_SIZE_16KB
76 #define THREAD_SIZE_ORDER (0)
77 #endif
78 #ifdef CONFIG_PAGE_SIZE_32KB
79 #define THREAD_SIZE_ORDER (0)
80 #endif
81 #ifdef CONFIG_PAGE_SIZE_64KB
82 #define THREAD_SIZE_ORDER (0)
83 #endif
84 
85 #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
86 #define THREAD_MASK (THREAD_SIZE - 1UL)
87 
88 #define STACK_WARN (THREAD_SIZE / 8)
89 
90 #define PREEMPT_ACTIVE 0x10000000
91 
92 /*
93  * thread information flags
94  * - these are process state flags that various assembly files may need to
95  * access
96  * - pending work-to-be-done flags are in LSW
97  * - other flags in MSW
98  */
99 #define TIF_SIGPENDING 1 /* signal pending */
100 #define TIF_NEED_RESCHED 2 /* rescheduling necessary */
101 #define TIF_SYSCALL_AUDIT 3 /* syscall auditing active */
102 #define TIF_SECCOMP 4 /* secure computing */
103 #define TIF_NOTIFY_RESUME 5 /* callback before returning to user */
104 #define TIF_RESTORE_SIGMASK 9 /* restore signal mask in do_signal() */
105 #define TIF_USEDFPU 16 /* FPU was used by this task this quantum (SMP) */
106 #define TIF_MEMDIE 18 /* is terminating due to OOM killer */
107 #define TIF_FIXADE 20 /* Fix address errors in software */
108 #define TIF_LOGADE 21 /* Log address errors to syslog */
109 #define TIF_32BIT_REGS 22 /* also implies 16/32 fprs */
110 #define TIF_32BIT_ADDR 23 /* 32-bit address space (o32/n32) */
111 #define TIF_FPUBOUND 24 /* thread bound to FPU-full CPU set */
112 #define TIF_LOAD_WATCH 25 /* If set, load watch registers */
113 #define TIF_SYSCALL_TRACE 31 /* syscall trace active */
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_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
119 #define _TIF_SECCOMP (1<<TIF_SECCOMP)
120 #define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
121 #define _TIF_USEDFPU (1<<TIF_USEDFPU)
122 #define _TIF_FIXADE (1<<TIF_FIXADE)
123 #define _TIF_LOGADE (1<<TIF_LOGADE)
124 #define _TIF_32BIT_REGS (1<<TIF_32BIT_REGS)
125 #define _TIF_32BIT_ADDR (1<<TIF_32BIT_ADDR)
126 #define _TIF_FPUBOUND (1<<TIF_FPUBOUND)
127 #define _TIF_LOAD_WATCH (1<<TIF_LOAD_WATCH)
128 
129 /* work to do in syscall_trace_leave() */
130 #define _TIF_WORK_SYSCALL_EXIT (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT)
131 
132 /* work to do on interrupt/exception return */
133 #define _TIF_WORK_MASK \
134  (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_NOTIFY_RESUME)
135 /* work to do on any return to u-space */
136 #define _TIF_ALLWORK_MASK (_TIF_WORK_MASK | _TIF_WORK_SYSCALL_EXIT)
137 
138 #endif /* __KERNEL__ */
139 
140 #endif /* _ASM_THREAD_INFO_H */