Linux kernel mirror (for testing)
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linux
1/*
2 * Copyright 2004-2010 Analog Devices Inc.
3 *
4 * Licensed under the GPL-2 or later.
5 */
6
7#ifndef _ASM_THREAD_INFO_H
8#define _ASM_THREAD_INFO_H
9
10#include <asm/page.h>
11#include <asm/entry.h>
12#include <asm/l1layout.h>
13#include <linux/compiler.h>
14
15#ifdef __KERNEL__
16
17/* Thread Align Mask to reach to the top of the stack
18 * for any process
19 */
20#define ALIGN_PAGE_MASK 0xffffe000
21
22/*
23 * Size of kernel stack for each process. This must be a power of 2...
24 */
25#define THREAD_SIZE_ORDER 1
26#define THREAD_SIZE 8192 /* 2 pages */
27#define STACK_WARN (THREAD_SIZE/8)
28
29#ifndef __ASSEMBLY__
30
31typedef unsigned long mm_segment_t;
32
33/*
34 * low level task data.
35 * If you change this, change the TI_* offsets below to match.
36 */
37
38struct thread_info {
39 struct task_struct *task; /* main task structure */
40 struct exec_domain *exec_domain; /* execution domain */
41 unsigned long flags; /* low level flags */
42 int cpu; /* cpu we're on */
43 int preempt_count; /* 0 => preemptable, <0 => BUG */
44 mm_segment_t addr_limit; /* address limit */
45 struct restart_block restart_block;
46#ifndef CONFIG_SMP
47 struct l1_scratch_task_info l1_task_info;
48#endif
49};
50
51/*
52 * macros/functions for gaining access to the thread information structure
53 */
54#define INIT_THREAD_INFO(tsk) \
55{ \
56 .task = &tsk, \
57 .exec_domain = &default_exec_domain, \
58 .flags = 0, \
59 .cpu = 0, \
60 .preempt_count = INIT_PREEMPT_COUNT, \
61 .restart_block = { \
62 .fn = do_no_restart_syscall, \
63 }, \
64}
65#define init_thread_info (init_thread_union.thread_info)
66#define init_stack (init_thread_union.stack)
67
68/* Given a task stack pointer, you can find its corresponding
69 * thread_info structure just by masking it to the THREAD_SIZE
70 * boundary (currently 8K as you can see above).
71 */
72__attribute_const__
73static inline struct thread_info *current_thread_info(void)
74{
75 struct thread_info *ti;
76 __asm__("%0 = sp;" : "=da"(ti));
77 return (struct thread_info *)((long)ti & ~((long)THREAD_SIZE-1));
78}
79
80#endif /* __ASSEMBLY__ */
81
82/*
83 * Offsets in thread_info structure, used in assembly code
84 */
85#define TI_TASK 0
86#define TI_EXECDOMAIN 4
87#define TI_FLAGS 8
88#define TI_CPU 12
89#define TI_PREEMPT 16
90
91#define PREEMPT_ACTIVE 0x4000000
92
93/*
94 * thread information flag bit numbers
95 */
96#define TIF_SYSCALL_TRACE 0 /* syscall trace active */
97#define TIF_SIGPENDING 1 /* signal pending */
98#define TIF_NEED_RESCHED 2 /* rescheduling necessary */
99#define TIF_MEMDIE 4 /* is terminating due to OOM killer */
100#define TIF_RESTORE_SIGMASK 5 /* restore signal mask in do_signal() */
101#define TIF_IRQ_SYNC 7 /* sync pipeline stage */
102#define TIF_NOTIFY_RESUME 8 /* callback before returning to user */
103#define TIF_SINGLESTEP 9
104
105/* as above, but as bit values */
106#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
107#define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
108#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
109#define _TIF_IRQ_SYNC (1<<TIF_IRQ_SYNC)
110#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
111#define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
112
113#define _TIF_WORK_MASK 0x0000FFFE /* work to do on interrupt/exception return */
114
115#endif /* __KERNEL__ */
116
117#endif /* _ASM_THREAD_INFO_H */