Linux kernel mirror (for testing)
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2/* thread_info.h: common low-level thread information accessors
3 *
4 * Copyright (C) 2002 David Howells (dhowells@redhat.com)
5 * - Incorporating suggestions made by Linus Torvalds
6 */
7
8#ifndef _LINUX_THREAD_INFO_H
9#define _LINUX_THREAD_INFO_H
10
11#include <linux/types.h>
12#include <linux/limits.h>
13#include <linux/bug.h>
14#include <linux/restart_block.h>
15#include <linux/errno.h>
16
17#ifdef CONFIG_THREAD_INFO_IN_TASK
18/*
19 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
20 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
21 * including <asm/current.h> can cause a circular dependency on some platforms.
22 */
23#include <asm/current.h>
24#define current_thread_info() ((struct thread_info *)current)
25#endif
26
27#include <linux/bitops.h>
28
29/*
30 * For per-arch arch_within_stack_frames() implementations, defined in
31 * asm/thread_info.h.
32 */
33enum {
34 BAD_STACK = -1,
35 NOT_STACK = 0,
36 GOOD_FRAME,
37 GOOD_STACK,
38};
39
40#ifdef CONFIG_GENERIC_ENTRY
41enum syscall_work_bit {
42 SYSCALL_WORK_BIT_SECCOMP,
43 SYSCALL_WORK_BIT_SYSCALL_TRACEPOINT,
44 SYSCALL_WORK_BIT_SYSCALL_TRACE,
45 SYSCALL_WORK_BIT_SYSCALL_EMU,
46 SYSCALL_WORK_BIT_SYSCALL_AUDIT,
47 SYSCALL_WORK_BIT_SYSCALL_USER_DISPATCH,
48 SYSCALL_WORK_BIT_SYSCALL_EXIT_TRAP,
49 SYSCALL_WORK_BIT_SYSCALL_RSEQ_SLICE,
50};
51
52#define SYSCALL_WORK_SECCOMP BIT(SYSCALL_WORK_BIT_SECCOMP)
53#define SYSCALL_WORK_SYSCALL_TRACEPOINT BIT(SYSCALL_WORK_BIT_SYSCALL_TRACEPOINT)
54#define SYSCALL_WORK_SYSCALL_TRACE BIT(SYSCALL_WORK_BIT_SYSCALL_TRACE)
55#define SYSCALL_WORK_SYSCALL_EMU BIT(SYSCALL_WORK_BIT_SYSCALL_EMU)
56#define SYSCALL_WORK_SYSCALL_AUDIT BIT(SYSCALL_WORK_BIT_SYSCALL_AUDIT)
57#define SYSCALL_WORK_SYSCALL_USER_DISPATCH BIT(SYSCALL_WORK_BIT_SYSCALL_USER_DISPATCH)
58#define SYSCALL_WORK_SYSCALL_EXIT_TRAP BIT(SYSCALL_WORK_BIT_SYSCALL_EXIT_TRAP)
59#define SYSCALL_WORK_SYSCALL_RSEQ_SLICE BIT(SYSCALL_WORK_BIT_SYSCALL_RSEQ_SLICE)
60#endif
61
62#include <asm/thread_info.h>
63
64#ifndef TIF_NEED_RESCHED_LAZY
65#ifdef CONFIG_ARCH_HAS_PREEMPT_LAZY
66#error Inconsistent PREEMPT_LAZY
67#endif
68#define TIF_NEED_RESCHED_LAZY TIF_NEED_RESCHED
69#define _TIF_NEED_RESCHED_LAZY _TIF_NEED_RESCHED
70#endif
71
72#ifndef TIF_RSEQ
73# define TIF_RSEQ TIF_NOTIFY_RESUME
74# define _TIF_RSEQ _TIF_NOTIFY_RESUME
75#endif
76
77#ifdef __KERNEL__
78
79#ifndef arch_set_restart_data
80#define arch_set_restart_data(restart) do { } while (0)
81#endif
82
83static inline long set_restart_fn(struct restart_block *restart,
84 long (*fn)(struct restart_block *))
85{
86 restart->fn = fn;
87 arch_set_restart_data(restart);
88 return -ERESTART_RESTARTBLOCK;
89}
90
91#ifndef THREAD_ALIGN
92#define THREAD_ALIGN THREAD_SIZE
93#endif
94
95#define THREADINFO_GFP (GFP_KERNEL_ACCOUNT | __GFP_ZERO)
96
97/*
98 * flag set/clear/test wrappers
99 * - pass TIF_xxxx constants to these functions
100 */
101
102static inline void set_ti_thread_flag(struct thread_info *ti, int flag)
103{
104 set_bit(flag, (unsigned long *)&ti->flags);
105}
106
107static inline void clear_ti_thread_flag(struct thread_info *ti, int flag)
108{
109 clear_bit(flag, (unsigned long *)&ti->flags);
110}
111
112static inline void update_ti_thread_flag(struct thread_info *ti, int flag,
113 bool value)
114{
115 if (value)
116 set_ti_thread_flag(ti, flag);
117 else
118 clear_ti_thread_flag(ti, flag);
119}
120
121static inline int test_and_set_ti_thread_flag(struct thread_info *ti, int flag)
122{
123 return test_and_set_bit(flag, (unsigned long *)&ti->flags);
124}
125
126static inline int test_and_clear_ti_thread_flag(struct thread_info *ti, int flag)
127{
128 return test_and_clear_bit(flag, (unsigned long *)&ti->flags);
129}
130
131static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
132{
133 return test_bit(flag, (unsigned long *)&ti->flags);
134}
135
136/*
137 * This may be used in noinstr code, and needs to be __always_inline to prevent
138 * inadvertent instrumentation.
139 */
140static __always_inline unsigned long read_ti_thread_flags(struct thread_info *ti)
141{
142 return READ_ONCE(ti->flags);
143}
144
145#define set_thread_flag(flag) \
146 set_ti_thread_flag(current_thread_info(), flag)
147#define clear_thread_flag(flag) \
148 clear_ti_thread_flag(current_thread_info(), flag)
149#define update_thread_flag(flag, value) \
150 update_ti_thread_flag(current_thread_info(), flag, value)
151#define test_and_set_thread_flag(flag) \
152 test_and_set_ti_thread_flag(current_thread_info(), flag)
153#define test_and_clear_thread_flag(flag) \
154 test_and_clear_ti_thread_flag(current_thread_info(), flag)
155#define test_thread_flag(flag) \
156 test_ti_thread_flag(current_thread_info(), flag)
157#define read_thread_flags() \
158 read_ti_thread_flags(current_thread_info())
159
160#define read_task_thread_flags(t) \
161 read_ti_thread_flags(task_thread_info(t))
162
163#ifdef CONFIG_GENERIC_ENTRY
164#define set_syscall_work(fl) \
165 set_bit(SYSCALL_WORK_BIT_##fl, ¤t_thread_info()->syscall_work)
166#define test_syscall_work(fl) \
167 test_bit(SYSCALL_WORK_BIT_##fl, ¤t_thread_info()->syscall_work)
168#define clear_syscall_work(fl) \
169 clear_bit(SYSCALL_WORK_BIT_##fl, ¤t_thread_info()->syscall_work)
170
171#define set_task_syscall_work(t, fl) \
172 set_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work)
173#define test_task_syscall_work(t, fl) \
174 test_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work)
175#define clear_task_syscall_work(t, fl) \
176 clear_bit(SYSCALL_WORK_BIT_##fl, &task_thread_info(t)->syscall_work)
177
178#else /* CONFIG_GENERIC_ENTRY */
179
180#define set_syscall_work(fl) \
181 set_ti_thread_flag(current_thread_info(), TIF_##fl)
182#define test_syscall_work(fl) \
183 test_ti_thread_flag(current_thread_info(), TIF_##fl)
184#define clear_syscall_work(fl) \
185 clear_ti_thread_flag(current_thread_info(), TIF_##fl)
186
187#define set_task_syscall_work(t, fl) \
188 set_ti_thread_flag(task_thread_info(t), TIF_##fl)
189#define test_task_syscall_work(t, fl) \
190 test_ti_thread_flag(task_thread_info(t), TIF_##fl)
191#define clear_task_syscall_work(t, fl) \
192 clear_ti_thread_flag(task_thread_info(t), TIF_##fl)
193#endif /* !CONFIG_GENERIC_ENTRY */
194
195#ifdef _ASM_GENERIC_BITOPS_INSTRUMENTED_NON_ATOMIC_H
196
197static __always_inline bool tif_test_bit(int bit)
198{
199 return arch_test_bit(bit,
200 (unsigned long *)(¤t_thread_info()->flags));
201}
202
203#else
204
205static __always_inline bool tif_test_bit(int bit)
206{
207 return test_bit(bit,
208 (unsigned long *)(¤t_thread_info()->flags));
209}
210
211#endif /* _ASM_GENERIC_BITOPS_INSTRUMENTED_NON_ATOMIC_H */
212
213static __always_inline bool tif_need_resched(void)
214{
215 return tif_test_bit(TIF_NEED_RESCHED);
216}
217
218#ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES
219static inline int arch_within_stack_frames(const void * const stack,
220 const void * const stackend,
221 const void *obj, unsigned long len)
222{
223 return 0;
224}
225#endif
226
227#ifndef arch_setup_new_exec
228static inline void arch_setup_new_exec(void) { }
229#endif
230
231void arch_task_cache_init(void); /* for CONFIG_SH */
232void arch_release_task_struct(struct task_struct *tsk);
233int arch_dup_task_struct(struct task_struct *dst,
234 struct task_struct *src);
235
236#endif /* __KERNEL__ */
237
238#endif /* _LINUX_THREAD_INFO_H */