tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/* MN10300 Low-level thread information
2 *
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
10 */
11
12#ifndef _ASM_THREAD_INFO_H
13#define _ASM_THREAD_INFO_H
14
15#ifdef __KERNEL__
16
17#include <asm/page.h>
18
19#define PREEMPT_ACTIVE 0x10000000
20
21#ifdef CONFIG_4KSTACKS
22#define THREAD_SIZE (4096)
23#define THREAD_SIZE_ORDER (0)
24#else
25#define THREAD_SIZE (8192)
26#define THREAD_SIZE_ORDER (1)
27#endif
28
29#define STACK_WARN (THREAD_SIZE / 8)
30
31/*
32 * low level task data that entry.S needs immediate access to
33 * - this struct should fit entirely inside of one cache line
34 * - this struct shares the supervisor stack pages
35 * - if the contents of this structure are changed, the assembly constants
36 * must also be changed
37 */
38#ifndef __ASSEMBLY__
39typedef struct {
40 unsigned long seg;
41} mm_segment_t;
42
43struct thread_info {
44 struct task_struct *task; /* main task structure */
45 struct exec_domain *exec_domain; /* execution domain */
46 struct pt_regs *frame; /* current exception frame */
47 unsigned long flags; /* low level flags */
48 __u32 cpu; /* current CPU */
49 __s32 preempt_count; /* 0 => preemptable, <0 => BUG */
50
51 mm_segment_t addr_limit; /* thread address space:
52 0-0xBFFFFFFF for user-thead
53 0-0xFFFFFFFF for kernel-thread
54 */
55 struct restart_block restart_block;
56
57 __u8 supervisor_stack[0];
58};
59
60#define thread_info_to_uregs(ti) \
61 ((struct pt_regs *) \
62 ((unsigned long)ti + THREAD_SIZE - sizeof(struct pt_regs)))
63
64#else /* !__ASSEMBLY__ */
65
66#ifndef __ASM_OFFSETS_H__
67#include <asm/asm-offsets.h>
68#endif
69
70#endif
71
72/*
73 * macros/functions for gaining access to the thread information structure
74 */
75#ifndef __ASSEMBLY__
76
77#define INIT_THREAD_INFO(tsk) \
78{ \
79 .task = &tsk, \
80 .exec_domain = &default_exec_domain, \
81 .flags = 0, \
82 .cpu = 0, \
83 .preempt_count = INIT_PREEMPT_COUNT, \
84 .addr_limit = KERNEL_DS, \
85 .restart_block = { \
86 .fn = do_no_restart_syscall, \
87 }, \
88}
89
90#define init_thread_info (init_thread_union.thread_info)
91#define init_stack (init_thread_union.stack)
92#define init_uregs \
93 ((struct pt_regs *) \
94 ((unsigned long) init_stack + THREAD_SIZE - sizeof(struct pt_regs)))
95
96extern struct thread_info *__current_ti;
97
98/* how to get the thread information struct from C */
99static inline __attribute__((const))
100struct thread_info *current_thread_info(void)
101{
102 struct thread_info *ti;
103 asm("mov sp,%0\n"
104 "and %1,%0\n"
105 : "=d" (ti)
106 : "i" (~(THREAD_SIZE - 1))
107 : "cc");
108 return ti;
109}
110
111static inline __attribute__((const))
112struct pt_regs *current_frame(void)
113{
114 return current_thread_info()->frame;
115}
116
117/* how to get the current stack pointer from C */
118static inline unsigned long current_stack_pointer(void)
119{
120 unsigned long sp;
121 asm("mov sp,%0; ":"=r" (sp));
122 return sp;
123}
124
125#ifndef CONFIG_KGDB
126void arch_release_thread_info(struct thread_info *ti);
127#endif
128#define get_thread_info(ti) get_task_struct((ti)->task)
129#define put_thread_info(ti) put_task_struct((ti)->task)
130
131#else /* !__ASSEMBLY__ */
132
133#ifndef __VMLINUX_LDS__
134/* how to get the thread information struct from ASM */
135.macro GET_THREAD_INFO reg
136 mov sp,\reg
137 and -THREAD_SIZE,\reg
138.endm
139#endif
140#endif
141
142/*
143 * thread information flags
144 * - these are process state flags that various assembly files may need to
145 * access
146 * - pending work-to-be-done flags are in LSW
147 * - other flags in MSW
148 */
149#define TIF_SYSCALL_TRACE 0 /* syscall trace active */
150#define TIF_NOTIFY_RESUME 1 /* resumption notification requested */
151#define TIF_SIGPENDING 2 /* signal pending */
152#define TIF_NEED_RESCHED 3 /* rescheduling necessary */
153#define TIF_SINGLESTEP 4 /* restore singlestep on return to user mode */
154#define TIF_RESTORE_SIGMASK 5 /* restore signal mask in do_signal() */
155#define TIF_POLLING_NRFLAG 16 /* true if poll_idle() is polling TIF_NEED_RESCHED */
156#define TIF_MEMDIE 17 /* is terminating due to OOM killer */
157
158#define _TIF_SYSCALL_TRACE +(1 << TIF_SYSCALL_TRACE)
159#define _TIF_NOTIFY_RESUME +(1 << TIF_NOTIFY_RESUME)
160#define _TIF_SIGPENDING +(1 << TIF_SIGPENDING)
161#define _TIF_NEED_RESCHED +(1 << TIF_NEED_RESCHED)
162#define _TIF_SINGLESTEP +(1 << TIF_SINGLESTEP)
163#define _TIF_POLLING_NRFLAG +(1 << TIF_POLLING_NRFLAG)
164
165#define _TIF_WORK_MASK 0x0000FFFE /* work to do on interrupt/exception return */
166#define _TIF_ALLWORK_MASK 0x0000FFFF /* work to do on any return to u-space */
167
168#endif /* __KERNEL__ */
169
170#endif /* _ASM_THREAD_INFO_H */