[PATCH] mutex subsystem, add atomic_xchg() to all arches
[linux-2.6.git] / include / asm-mips / thread_info.h
1 /* thread_info.h: MIPS low-level thread information
2  *
3  * Copyright (C) 2002  David Howells (dhowells@redhat.com)
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 #include <linux/config.h>
13
14 #ifndef __ASSEMBLY__
15
16 #include <asm/processor.h>
17
18 /*
19  * low level task data that entry.S needs immediate access to
20  * - this struct should fit entirely inside of one cache line
21  * - this struct shares the supervisor stack pages
22  * - if the contents of this structure are changed, the assembly constants
23  *   must also be changed
24  */
25 struct thread_info {
26         struct task_struct      *task;          /* main task structure */
27         struct exec_domain      *exec_domain;   /* execution domain */
28         unsigned long           flags;          /* low level flags */
29         unsigned long           tp_value;       /* thread pointer */
30         __u32                   cpu;            /* current CPU */
31         int                     preempt_count;  /* 0 => preemptable, <0 => BUG */
32
33         mm_segment_t            addr_limit;     /* thread address space:
34                                                    0-0xBFFFFFFF for user-thead
35                                                    0-0xFFFFFFFF for kernel-thread
36                                                 */
37         struct restart_block    restart_block;
38 };
39
40 /*
41  * macros/functions for gaining access to the thread information structure
42  *
43  * preempt_count needs to be 1 initially, until the scheduler is functional.
44  */
45 #define INIT_THREAD_INFO(tsk)                   \
46 {                                               \
47         .task           = &tsk,                 \
48         .exec_domain    = &default_exec_domain, \
49         .flags          = 0,                    \
50         .cpu            = 0,                    \
51         .preempt_count  = 1,                    \
52         .addr_limit     = KERNEL_DS,            \
53         .restart_block  = {                     \
54                 .fn = do_no_restart_syscall,    \
55         },                                      \
56 }
57
58 #define init_thread_info        (init_thread_union.thread_info)
59 #define init_stack              (init_thread_union.stack)
60
61 /* How to get the thread information struct from C.  */
62 register struct thread_info *__current_thread_info __asm__("$28");
63 #define current_thread_info()  __current_thread_info
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_64KB
79 #define THREAD_SIZE_ORDER (0)
80 #endif
81
82 #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
83 #define THREAD_MASK (THREAD_SIZE - 1UL)
84
85 #ifdef CONFIG_DEBUG_STACK_USAGE
86 #define alloc_thread_info(tsk)                                  \
87 ({                                                              \
88         struct thread_info *ret;                                \
89                                                                 \
90         ret = kmalloc(THREAD_SIZE, GFP_KERNEL);                 \
91         if (ret)                                                \
92                 memset(ret, 0, THREAD_SIZE);                    \
93         ret;                                                    \
94 })
95 #else
96 #define alloc_thread_info(tsk) kmalloc(THREAD_SIZE, GFP_KERNEL)
97 #endif
98
99 #define free_thread_info(info) kfree(info)
100 #define get_thread_info(ti) get_task_struct((ti)->task)
101 #define put_thread_info(ti) put_task_struct((ti)->task)
102
103 #endif /* !__ASSEMBLY__ */
104
105 #define PREEMPT_ACTIVE          0x10000000
106
107 /*
108  * thread information flags
109  * - these are process state flags that various assembly files may need to
110  *   access
111  * - pending work-to-be-done flags are in LSW
112  * - other flags in MSW
113  */
114 #define TIF_NOTIFY_RESUME       1       /* resumption notification requested */
115 #define TIF_SIGPENDING          2       /* signal pending */
116 #define TIF_NEED_RESCHED        3       /* rescheduling necessary */
117 #define TIF_SYSCALL_AUDIT       4       /* syscall auditing active */
118 #define TIF_SECCOMP             5       /* secure computing */
119 #define TIF_USEDFPU             16      /* FPU was used by this task this quantum (SMP) */
120 #define TIF_POLLING_NRFLAG      17      /* true if poll_idle() is polling TIF_NEED_RESCHED */
121 #define TIF_MEMDIE              18
122 #define TIF_SYSCALL_TRACE       31      /* syscall trace active */
123
124 #define _TIF_SYSCALL_TRACE      (1<<TIF_SYSCALL_TRACE)
125 #define _TIF_NOTIFY_RESUME      (1<<TIF_NOTIFY_RESUME)
126 #define _TIF_SIGPENDING         (1<<TIF_SIGPENDING)
127 #define _TIF_NEED_RESCHED       (1<<TIF_NEED_RESCHED)
128 #define _TIF_SYSCALL_AUDIT      (1<<TIF_SYSCALL_AUDIT)
129 #define _TIF_SECCOMP            (1<<TIF_SECCOMP)
130 #define _TIF_USEDFPU            (1<<TIF_USEDFPU)
131 #define _TIF_POLLING_NRFLAG     (1<<TIF_POLLING_NRFLAG)
132
133 /* work to do on interrupt/exception return */
134 #define _TIF_WORK_MASK          (0x0000ffef & ~_TIF_SECCOMP)
135 /* work to do on any return to u-space */
136 #define _TIF_ALLWORK_MASK       (0x8000ffff & ~_TIF_SECCOMP)
137
138 #endif /* __KERNEL__ */
139
140 #endif /* _ASM_THREAD_INFO_H */