tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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 struct exec_domain *exec_domain; /* execution domain */
30 unsigned long flags; /* low level flags */
31 unsigned long status; /* thread-synchronous flags */
32 __u32 homecache_cpu; /* CPU we are homecached on */
33 __u32 cpu; /* current CPU */
34 int preempt_count; /* 0 => preemptable,
35 <0 => BUG */
36
37 mm_segment_t addr_limit; /* thread address space
38 (KERNEL_DS or USER_DS) */
39 struct restart_block restart_block;
40 struct single_step_state *step_state; /* single step state
41 (if non-zero) */
42 int align_ctl; /* controls unaligned access */
43#ifdef __tilegx__
44 unsigned long unalign_jit_tmp[4]; /* temp r0..r3 storage */
45 void __user *unalign_jit_base; /* unalign fixup JIT base */
46#endif
47};
48
49/*
50 * macros/functions for gaining access to the thread information structure.
51 */
52#define INIT_THREAD_INFO(tsk) \
53{ \
54 .task = &tsk, \
55 .exec_domain = &default_exec_domain, \
56 .flags = 0, \
57 .cpu = 0, \
58 .preempt_count = INIT_PREEMPT_COUNT, \
59 .addr_limit = KERNEL_DS, \
60 .restart_block = { \
61 .fn = do_no_restart_syscall, \
62 }, \
63 .step_state = NULL, \
64 .align_ctl = 0, \
65}
66
67#define init_thread_info (init_thread_union.thread_info)
68#define init_stack (init_thread_union.stack)
69
70#endif /* !__ASSEMBLY__ */
71
72#if PAGE_SIZE < 8192
73#define THREAD_SIZE_ORDER (13 - PAGE_SHIFT)
74#else
75#define THREAD_SIZE_ORDER (0)
76#endif
77#define THREAD_SIZE_PAGES (1 << THREAD_SIZE_ORDER)
78
79#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
80#define LOG2_THREAD_SIZE (PAGE_SHIFT + THREAD_SIZE_ORDER)
81
82#define STACK_WARN (THREAD_SIZE/8)
83
84#ifndef __ASSEMBLY__
85
86void arch_release_thread_info(struct thread_info *info);
87
88/* How to get the thread information struct from C. */
89register unsigned long stack_pointer __asm__("sp");
90
91#define current_thread_info() \
92 ((struct thread_info *)(stack_pointer & -THREAD_SIZE))
93
94/* Sit on a nap instruction until interrupted. */
95extern void smp_nap(void);
96
97/* Enable interrupts racelessly and nap forever: helper for arch_cpu_idle(). */
98extern void _cpu_idle(void);
99
100#else /* __ASSEMBLY__ */
101
102/*
103 * How to get the thread information struct from assembly.
104 * Note that we use different macros since different architectures
105 * have different semantics in their "mm" instruction and we would
106 * like to guarantee that the macro expands to exactly one instruction.
107 */
108#ifdef __tilegx__
109#define EXTRACT_THREAD_INFO(reg) mm reg, zero, LOG2_THREAD_SIZE, 63
110#else
111#define GET_THREAD_INFO(reg) mm reg, sp, zero, LOG2_THREAD_SIZE, 31
112#endif
113
114#endif /* !__ASSEMBLY__ */
115
116/*
117 * Thread information flags that various assembly files may need to access.
118 * Keep flags accessed frequently in low bits, particular since it makes
119 * it easier to build constants in assembly.
120 */
121#define TIF_SIGPENDING 0 /* signal pending */
122#define TIF_NEED_RESCHED 1 /* rescheduling necessary */
123#define TIF_SINGLESTEP 2 /* restore singlestep on return to
124 user mode */
125#define TIF_ASYNC_TLB 3 /* got an async TLB fault in kernel */
126#define TIF_SYSCALL_TRACE 4 /* syscall trace active */
127#define TIF_SYSCALL_AUDIT 5 /* syscall auditing active */
128#define TIF_SECCOMP 6 /* secure computing */
129#define TIF_MEMDIE 7 /* OOM killer at work */
130#define TIF_NOTIFY_RESUME 8 /* callback before returning to user */
131#define TIF_SYSCALL_TRACEPOINT 9 /* syscall tracepoint instrumentation */
132#define TIF_POLLING_NRFLAG 10 /* idle is polling for TIF_NEED_RESCHED */
133
134#define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
135#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
136#define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
137#define _TIF_ASYNC_TLB (1<<TIF_ASYNC_TLB)
138#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
139#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
140#define _TIF_SECCOMP (1<<TIF_SECCOMP)
141#define _TIF_MEMDIE (1<<TIF_MEMDIE)
142#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
143#define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
144#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
145
146/* Work to do on any return to user space. */
147#define _TIF_ALLWORK_MASK \
148 (_TIF_SIGPENDING|_TIF_NEED_RESCHED|_TIF_SINGLESTEP|\
149 _TIF_ASYNC_TLB|_TIF_NOTIFY_RESUME)
150
151/* Work to do at syscall entry. */
152#define _TIF_SYSCALL_ENTRY_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT)
153
154/* Work to do at syscall exit. */
155#define _TIF_SYSCALL_EXIT_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT)
156
157/*
158 * Thread-synchronous status.
159 *
160 * This is different from the flags in that nobody else
161 * ever touches our thread-synchronous status, so we don't
162 * have to worry about atomic accesses.
163 */
164#ifdef __tilegx__
165#define TS_COMPAT 0x0001 /* 32-bit compatibility mode */
166#endif
167#define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal */
168
169#ifndef __ASSEMBLY__
170#define HAVE_SET_RESTORE_SIGMASK 1
171static inline void set_restore_sigmask(void)
172{
173 struct thread_info *ti = current_thread_info();
174 ti->status |= TS_RESTORE_SIGMASK;
175 WARN_ON(!test_bit(TIF_SIGPENDING, &ti->flags));
176}
177static inline void clear_restore_sigmask(void)
178{
179 current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
180}
181static inline bool test_restore_sigmask(void)
182{
183 return current_thread_info()->status & TS_RESTORE_SIGMASK;
184}
185static inline bool test_and_clear_restore_sigmask(void)
186{
187 struct thread_info *ti = current_thread_info();
188 if (!(ti->status & TS_RESTORE_SIGMASK))
189 return false;
190 ti->status &= ~TS_RESTORE_SIGMASK;
191 return true;
192}
193#endif /* !__ASSEMBLY__ */
194
195#endif /* _ASM_TILE_THREAD_INFO_H */