1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
4 *
5 * Vineetg: Oct 2009
6 * No need for ARC specific thread_info allocator (kmalloc/free). This is
7 * anyways one page allocation, thus slab alloc can be short-circuited and
8 * the generic version (get_free_page) would be loads better.
9 *
10 * Sameer Dhavale: Codito Technologies 2004
11 */
12
13 #ifndef _ASM_THREAD_INFO_H
14 #define _ASM_THREAD_INFO_H
15
16 #include <asm/page.h>
17
18 #ifdef CONFIG_16KSTACKS
19 #define THREAD_SIZE_ORDER 1
20 #else
21 #define THREAD_SIZE_ORDER 0
22 #endif
23
24 #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
25 #define THREAD_SHIFT (PAGE_SHIFT << THREAD_SIZE_ORDER)
26
27 #ifndef __ASSEMBLY__
28
29 #include <linux/thread_info.h>
30 #include <asm/segment.h>
31
32 /*
33 * low level task data that entry.S needs immediate access to
34 * - this struct should fit entirely inside of one cache line
35 * - this struct shares the supervisor stack pages
36 * - if the contents of this structure are changed, the assembly constants
37 * must also be changed
38 */
39 struct thread_info {
40 unsigned long flags; /* low level flags */
41 int preempt_count; /* 0 => preemptable, <0 => BUG */
42 struct task_struct *task; /* main task structure */
43 mm_segment_t addr_limit; /* thread address space */
44 __u32 cpu; /* current CPU */
45 unsigned long thr_ptr; /* TLS ptr */
46 };
47
48 /*
49 * macros/functions for gaining access to the thread information structure
50 *
51 * preempt_count needs to be 1 initially, until the scheduler is functional.
52 */
53 #define INIT_THREAD_INFO(tsk) \
54 { \
55 .task = &tsk, \
56 .flags = 0, \
57 .cpu = 0, \
58 .preempt_count = INIT_PREEMPT_COUNT, \
59 .addr_limit = KERNEL_DS, \
60 }
61
62 static inline __attribute_const__ struct thread_info *current_thread_info(void)
63 {
64 register unsigned long sp asm("sp");
65 return (struct thread_info *)(sp & ~(THREAD_SIZE - 1));
66 }
67
68 #endif /* !__ASSEMBLY__ */
69
70 /*
71 * thread information flags
72 * - these are process state flags that various assembly files may need to
73 * access
74 * - pending work-to-be-done flags are in LSW
75 * - other flags in MSW
76 */
77 #define TIF_RESTORE_SIGMASK 0 /* restore sig mask in do_signal() */
78 #define TIF_NOTIFY_RESUME 1 /* resumption notification requested */
79 #define TIF_SIGPENDING 2 /* signal pending */
80 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */
81 #define TIF_SYSCALL_AUDIT 4 /* syscall auditing active */
82 #define TIF_SYSCALL_TRACE 15 /* syscall trace active */
83
84 /* true if poll_idle() is polling TIF_NEED_RESCHED */
85 #define TIF_MEMDIE 16
86
87 #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
88 #define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
89 #define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
90 #define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
91 #define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
92 #define _TIF_MEMDIE (1<<TIF_MEMDIE)
93
94 /* work to do on interrupt/exception return */
95 #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
96 _TIF_NOTIFY_RESUME)
97
98 /*
99 * _TIF_ALLWORK_MASK includes SYSCALL_TRACE, but we don't need it.
100 * SYSCALL_TRACE is anyway seperately/unconditionally tested right after a
101 * syscall, so all that reamins to be tested is _TIF_WORK_MASK
102 */
103
104 #endif /* _ASM_THREAD_INFO_H */