summaryrefslogtreecommitdiffstats
path: root/arch/tile/include/asm/thread_info.h
blob: e9c670d7a7fe2e13c1edd65c410f840ba75f5e32 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
/*
 * Copyright (C) 2002  David Howells (dhowells@redhat.com)
 * Copyright 2010 Tilera Corporation. All Rights Reserved.
 *
 *   This program is free software; you can redistribute it and/or
 *   modify it under the terms of the GNU General Public License
 *   as published by the Free Software Foundation, version 2.
 *
 *   This program is distributed in the hope that it will be useful, but
 *   WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 *   NON INFRINGEMENT.  See the GNU General Public License for
 *   more details.
 */

#ifndef _ASM_TILE_THREAD_INFO_H
#define _ASM_TILE_THREAD_INFO_H

#include <asm/processor.h>
#include <asm/page.h>
#ifndef __ASSEMBLY__

/*
 * Low level task data that assembly code needs immediate access to.
 * The structure is placed at the bottom of the supervisor stack.
 */
struct thread_info {
	struct task_struct	*task;		/* main task structure */
	struct exec_domain	*exec_domain;	/* execution domain */
	unsigned long		flags;		/* low level flags */
	unsigned long		status;		/* thread-synchronous flags */
	__u32			homecache_cpu;	/* CPU we are homecached on */
	__u32			cpu;		/* current CPU */
	int			preempt_count;	/* 0 => preemptable,
						   <0 => BUG */

	mm_segment_t		addr_limit;	/* thread address space
						   (KERNEL_DS or USER_DS) */
	struct restart_block	restart_block;
	struct single_step_state *step_state;	/* single step state
						   (if non-zero) */
};

/*
 * macros/functions for gaining access to the thread information structure.
 */
#define INIT_THREAD_INFO(tsk)			\
{						\
	.task		= &tsk,			\
	.exec_domain	= &default_exec_domain,	\
	.flags		= 0,			\
	.cpu		= 0,			\
	.preempt_count	= INIT_PREEMPT_COUNT,	\
	.addr_limit	= KERNEL_DS,		\
	.restart_block	= {			\
		.fn = do_no_restart_syscall,	\
	},					\
	.step_state	= NULL,			\
}

#define init_thread_info	(init_thread_union.thread_info)
#define init_stack		(init_thread_union.stack)

#endif /* !__ASSEMBLY__ */

#if PAGE_SIZE < 8192
#define THREAD_SIZE_ORDER (13 - PAGE_SHIFT)
#else
#define THREAD_SIZE_ORDER (0)
#endif
#define THREAD_SIZE_PAGES (1 << THREAD_SIZE_ORDER)

#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
#define LOG2_THREAD_SIZE (PAGE_SHIFT + THREAD_SIZE_ORDER)

#define STACK_WARN             (THREAD_SIZE/8)

#ifndef __ASSEMBLY__

void arch_release_thread_info(struct thread_info *info);

/* How to get the thread information struct from C. */
register unsigned long stack_pointer __asm__("sp");

#define current_thread_info() \
  ((struct thread_info *)(stack_pointer & -THREAD_SIZE))

/* Sit on a nap instruction until interrupted. */
extern void smp_nap(void);

/* Enable interrupts racelessly and nap forever: helper for cpu_idle(). */
extern void _cpu_idle(void);

#else /* __ASSEMBLY__ */

/*
 * How to get the thread information struct from assembly.
 * Note that we use different macros since different architectures
 * have different semantics in their "mm" instruction and we would
 * like to guarantee that the macro expands to exactly one instruction.
 */
#ifdef __tilegx__
#define EXTRACT_THREAD_INFO(reg) mm reg, zero, LOG2_THREAD_SIZE, 63
#else
#define GET_THREAD_INFO(reg) mm reg, sp, zero, LOG2_THREAD_SIZE, 31
#endif

#endif /* !__ASSEMBLY__ */

#define PREEMPT_ACTIVE		0x10000000

/*
 * Thread information flags that various assembly files may need to access.
 * Keep flags accessed frequently in low bits, particular since it makes
 * it easier to build constants in assembly.
 */
#define TIF_SIGPENDING		0	/* signal pending */
#define TIF_NEED_RESCHED	1	/* rescheduling necessary */
#define TIF_SINGLESTEP		2	/* restore singlestep on return to
					   user mode */
#define TIF_ASYNC_TLB		3	/* got an async TLB fault in kernel */
#define TIF_SYSCALL_TRACE	4	/* syscall trace active */
#define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
#define TIF_SECCOMP		6	/* secure computing */
#define TIF_MEMDIE		7	/* OOM killer at work */
#define TIF_NOTIFY_RESUME	8	/* callback before returning to user */

#define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
#define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
#define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
#define _TIF_ASYNC_TLB		(1<<TIF_ASYNC_TLB)
#define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
#define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
#define _TIF_SECCOMP		(1<<TIF_SECCOMP)
#define _TIF_MEMDIE		(1<<TIF_MEMDIE)
#define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)

/* Work to do on any return to user space. */
#define _TIF_ALLWORK_MASK \
  (_TIF_SIGPENDING|_TIF_NEED_RESCHED|_TIF_SINGLESTEP|\
   _TIF_ASYNC_TLB|_TIF_NOTIFY_RESUME)

/*
 * Thread-synchronous status.
 *
 * This is different from the flags in that nobody else
 * ever touches our thread-synchronous status, so we don't
 * have to worry about atomic accesses.
 */
#ifdef __tilegx__
#define TS_COMPAT		0x0001	/* 32-bit compatibility mode */
#endif
#define TS_POLLING		0x0004	/* in idle loop but not sleeping */
#define TS_RESTORE_SIGMASK	0x0008	/* restore signal mask in do_signal */

#define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING)

#ifndef __ASSEMBLY__
#define HAVE_SET_RESTORE_SIGMASK	1
static inline void set_restore_sigmask(void)
{
	struct thread_info *ti = current_thread_info();
	ti->status |= TS_RESTORE_SIGMASK;
	WARN_ON(!test_bit(TIF_SIGPENDING, &ti->flags));
}
static inline void clear_restore_sigmask(void)
{
	current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
}
static inline bool test_restore_sigmask(void)
{
	return current_thread_info()->status & TS_RESTORE_SIGMASK;
}
static inline bool test_and_clear_restore_sigmask(void)
{
	struct thread_info *ti = current_thread_info();
	if (!(ti->status & TS_RESTORE_SIGMASK))
		return false;
	ti->status &= ~TS_RESTORE_SIGMASK;
	return true;
}
#endif	/* !__ASSEMBLY__ */

#endif /* _ASM_TILE_THREAD_INFO_H */
OpenPOWER on IntegriCloud