Linux kernel mirror (for testing)
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1/*
2 * Copyright (C) 2002 David Howells (dhowells@redhat.com)
3 * Copyright 2010 Tilera Corporation. All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation, version 2.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
12 * NON INFRINGEMENT. See the GNU General Public License for
13 * more details.
14 */
15
16#ifndef _ASM_TILE_THREAD_INFO_H
17#define _ASM_TILE_THREAD_INFO_H
18
19#include <asm/processor.h>
20#include <asm/page.h>
21#ifndef __ASSEMBLY__
22
23/*
24 * Low level task data that assembly code needs immediate access to.
25 * The structure is placed at the bottom of the supervisor stack.
26 */
27struct thread_info {
28 struct task_struct *task; /* main task structure */
29 unsigned long flags; /* low level flags */
30 unsigned long status; /* thread-synchronous flags */
31 __u32 homecache_cpu; /* CPU we are homecached on */
32 __u32 cpu; /* current CPU */
33 int preempt_count; /* 0 => preemptable,
34 <0 => BUG */
35
36 mm_segment_t addr_limit; /* thread address space
37 (KERNEL_DS or USER_DS) */
38 struct single_step_state *step_state; /* single step state
39 (if non-zero) */
40 int align_ctl; /* controls unaligned access */
41#ifdef __tilegx__
42 unsigned long unalign_jit_tmp[4]; /* temp r0..r3 storage */
43 void __user *unalign_jit_base; /* unalign fixup JIT base */
44#endif
45 bool in_backtrace; /* currently doing backtrace? */
46};
47
48/*
49 * macros/functions for gaining access to the thread information structure.
50 */
51#define INIT_THREAD_INFO(tsk) \
52{ \
53 .task = &tsk, \
54 .flags = 0, \
55 .cpu = 0, \
56 .preempt_count = INIT_PREEMPT_COUNT, \
57 .addr_limit = KERNEL_DS, \
58 .step_state = NULL, \
59 .align_ctl = 0, \
60}
61
62#define init_thread_info (init_thread_union.thread_info)
63#define init_stack (init_thread_union.stack)
64
65#endif /* !__ASSEMBLY__ */
66
67#if PAGE_SIZE < 8192
68#define THREAD_SIZE_ORDER (13 - PAGE_SHIFT)
69#else
70#define THREAD_SIZE_ORDER (0)
71#endif
72#define THREAD_SIZE_PAGES (1 << THREAD_SIZE_ORDER)
73
74#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
75#define LOG2_THREAD_SIZE (PAGE_SHIFT + THREAD_SIZE_ORDER)
76
77#define STACK_WARN (THREAD_SIZE/8)
78
79#ifndef __ASSEMBLY__
80
81void arch_release_thread_info(struct thread_info *info);
82
83/* How to get the thread information struct from C. */
84register unsigned long stack_pointer __asm__("sp");
85
86#define current_thread_info() \
87 ((struct thread_info *)(stack_pointer & -THREAD_SIZE))
88
89/* Sit on a nap instruction until interrupted. */
90extern void smp_nap(void);
91
92/* Enable interrupts racelessly and nap forever: helper for arch_cpu_idle(). */
93extern void _cpu_idle(void);
94
95#else /* __ASSEMBLY__ */
96
97/*
98 * How to get the thread information struct from assembly.
99 * Note that we use different macros since different architectures
100 * have different semantics in their "mm" instruction and we would
101 * like to guarantee that the macro expands to exactly one instruction.
102 */
103#ifdef __tilegx__
104#define EXTRACT_THREAD_INFO(reg) mm reg, zero, LOG2_THREAD_SIZE, 63
105#else
106#define GET_THREAD_INFO(reg) mm reg, sp, zero, LOG2_THREAD_SIZE, 31
107#endif
108
109#endif /* !__ASSEMBLY__ */
110
111/*
112 * Thread information flags that various assembly files may need to access.
113 * Keep flags accessed frequently in low bits, particular since it makes
114 * it easier to build constants in assembly.
115 */
116#define TIF_SIGPENDING 0 /* signal pending */
117#define TIF_NEED_RESCHED 1 /* rescheduling necessary */
118#define TIF_SINGLESTEP 2 /* restore singlestep on return to
119 user mode */
120#define TIF_ASYNC_TLB 3 /* got an async TLB fault in kernel */
121#define TIF_SYSCALL_TRACE 4 /* syscall trace active */
122#define TIF_SYSCALL_AUDIT 5 /* syscall auditing active */
123#define TIF_SECCOMP 6 /* secure computing */
124#define TIF_MEMDIE 7 /* OOM killer at work */
125#define TIF_NOTIFY_RESUME 8 /* callback before returning to user */
126#define TIF_SYSCALL_TRACEPOINT 9 /* syscall tracepoint instrumentation */
127#define TIF_POLLING_NRFLAG 10 /* idle is polling for TIF_NEED_RESCHED */
128#define TIF_NOHZ 11 /* in adaptive nohz mode */
129
130#define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
131#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
132#define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
133#define _TIF_ASYNC_TLB (1<<TIF_ASYNC_TLB)
134#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
135#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
136#define _TIF_SECCOMP (1<<TIF_SECCOMP)
137#define _TIF_MEMDIE (1<<TIF_MEMDIE)
138#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
139#define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
140#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
141#define _TIF_NOHZ (1<<TIF_NOHZ)
142
143/* Work to do on any return to user space. */
144#define _TIF_ALLWORK_MASK \
145 (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_SINGLESTEP | \
146 _TIF_ASYNC_TLB | _TIF_NOTIFY_RESUME | _TIF_NOHZ)
147
148/* Work to do at syscall entry. */
149#define _TIF_SYSCALL_ENTRY_WORK \
150 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_NOHZ)
151
152/* Work to do at syscall exit. */
153#define _TIF_SYSCALL_EXIT_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT)
154
155/*
156 * Thread-synchronous status.
157 *
158 * This is different from the flags in that nobody else
159 * ever touches our thread-synchronous status, so we don't
160 * have to worry about atomic accesses.
161 */
162#ifdef __tilegx__
163#define TS_COMPAT 0x0001 /* 32-bit compatibility mode */
164#endif
165#define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal */
166
167#ifndef __ASSEMBLY__
168#define HAVE_SET_RESTORE_SIGMASK 1
169static inline void set_restore_sigmask(void)
170{
171 struct thread_info *ti = current_thread_info();
172 ti->status |= TS_RESTORE_SIGMASK;
173 WARN_ON(!test_bit(TIF_SIGPENDING, &ti->flags));
174}
175static inline void clear_restore_sigmask(void)
176{
177 current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
178}
179static inline bool test_restore_sigmask(void)
180{
181 return current_thread_info()->status & TS_RESTORE_SIGMASK;
182}
183static inline bool test_and_clear_restore_sigmask(void)
184{
185 struct thread_info *ti = current_thread_info();
186 if (!(ti->status & TS_RESTORE_SIGMASK))
187 return false;
188 ti->status &= ~TS_RESTORE_SIGMASK;
189 return true;
190}
191#endif /* !__ASSEMBLY__ */
192
193#endif /* _ASM_TILE_THREAD_INFO_H */