1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * include/linux/irqflags.h
4 *
5 * IRQ flags tracing: follow the state of the hardirq and softirq flags and
6 * provide callbacks for transitions between ON and OFF states.
7 *
8 * This file gets included from lowlevel asm headers too, to provide
9 * wrapped versions of the local_irq_*() APIs, based on the
10 * raw_local_irq_*() macros from the lowlevel headers.
11 */
12#ifndef _LINUX_TRACE_IRQFLAGS_H
13#define _LINUX_TRACE_IRQFLAGS_H
14
15#include <linux/irqflags_types.h>
16#include <linux/typecheck.h>
17#include <linux/cleanup.h>
18#include <asm/irqflags.h>
19#include <asm/percpu.h>
20
21struct task_struct;
22
23/* Currently lockdep_softirqs_on/off is used only by lockdep */
24#ifdef CONFIG_PROVE_LOCKING
25 extern void lockdep_softirqs_on(unsigned long ip);
26 extern void lockdep_softirqs_off(unsigned long ip);
27 extern void lockdep_hardirqs_on_prepare(void);
28 extern void lockdep_hardirqs_on(unsigned long ip);
29 extern void lockdep_hardirqs_off(unsigned long ip);
30 extern void lockdep_cleanup_dead_cpu(unsigned int cpu,
31 struct task_struct *idle);
32#else
33 static inline void lockdep_softirqs_on(unsigned long ip) { }
34 static inline void lockdep_softirqs_off(unsigned long ip) { }
35 static inline void lockdep_hardirqs_on_prepare(void) { }
36 static inline void lockdep_hardirqs_on(unsigned long ip) { }
37 static inline void lockdep_hardirqs_off(unsigned long ip) { }
38 static inline void lockdep_cleanup_dead_cpu(unsigned int cpu,
39 struct task_struct *idle) {}
40#endif
41
42#ifdef CONFIG_TRACE_IRQFLAGS
43
44DECLARE_PER_CPU(int, hardirqs_enabled);
45DECLARE_PER_CPU(int, hardirq_context);
46
47extern void trace_hardirqs_on_prepare(void);
48extern void trace_hardirqs_off_finish(void);
49extern void trace_hardirqs_on(void);
50extern void trace_hardirqs_off(void);
51
52# define lockdep_hardirq_context() (raw_cpu_read(hardirq_context))
53# define lockdep_softirq_context(p) ((p)->softirq_context)
54# define lockdep_hardirqs_enabled() (this_cpu_read(hardirqs_enabled))
55# define lockdep_softirqs_enabled(p) ((p)->softirqs_enabled)
56# define lockdep_hardirq_enter() \
57do { \
58 if (__this_cpu_inc_return(hardirq_context) == 1)\
59 current->hardirq_threaded = 0; \
60} while (0)
61# define lockdep_hardirq_threaded() \
62do { \
63 current->hardirq_threaded = 1; \
64} while (0)
65# define lockdep_hardirq_exit() \
66do { \
67 __this_cpu_dec(hardirq_context); \
68} while (0)
69
70# define lockdep_hrtimer_enter(__hrtimer) \
71({ \
72 bool __expires_hardirq = true; \
73 \
74 if (!__hrtimer->is_hard) { \
75 current->irq_config = 1; \
76 __expires_hardirq = false; \
77 } \
78 __expires_hardirq; \
79})
80
81# define lockdep_hrtimer_exit(__expires_hardirq) \
82 do { \
83 if (!__expires_hardirq) \
84 current->irq_config = 0; \
85 } while (0)
86
87# define lockdep_posixtimer_enter() \
88 do { \
89 current->irq_config = 1; \
90 } while (0)
91
92# define lockdep_posixtimer_exit() \
93 do { \
94 current->irq_config = 0; \
95 } while (0)
96
97# define lockdep_irq_work_enter(_flags) \
98 do { \
99 if (!((_flags) & IRQ_WORK_HARD_IRQ)) \
100 current->irq_config = 1; \
101 } while (0)
102# define lockdep_irq_work_exit(_flags) \
103 do { \
104 if (!((_flags) & IRQ_WORK_HARD_IRQ)) \
105 current->irq_config = 0; \
106 } while (0)
107
108#else
109# define trace_hardirqs_on_prepare() do { } while (0)
110# define trace_hardirqs_off_finish() do { } while (0)
111# define trace_hardirqs_on() do { } while (0)
112# define trace_hardirqs_off() do { } while (0)
113# define lockdep_hardirq_context() 0
114# define lockdep_softirq_context(p) 0
115# define lockdep_hardirqs_enabled() 0
116# define lockdep_softirqs_enabled(p) 0
117# define lockdep_hardirq_enter() do { } while (0)
118# define lockdep_hardirq_threaded() do { } while (0)
119# define lockdep_hardirq_exit() do { } while (0)
120# define lockdep_softirq_enter() do { } while (0)
121# define lockdep_softirq_exit() do { } while (0)
122# define lockdep_hrtimer_enter(__hrtimer) false
123# define lockdep_hrtimer_exit(__context) do { (void)(__context); } while (0)
124# define lockdep_posixtimer_enter() do { } while (0)
125# define lockdep_posixtimer_exit() do { } while (0)
126# define lockdep_irq_work_enter(__work) do { } while (0)
127# define lockdep_irq_work_exit(__work) do { } while (0)
128#endif
129
130#if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT)
131# define lockdep_softirq_enter() \
132do { \
133 current->softirq_context++; \
134} while (0)
135# define lockdep_softirq_exit() \
136do { \
137 current->softirq_context--; \
138} while (0)
139
140#else
141# define lockdep_softirq_enter() do { } while (0)
142# define lockdep_softirq_exit() do { } while (0)
143#endif
144
145#if defined(CONFIG_IRQSOFF_TRACER) || \
146 defined(CONFIG_PREEMPT_TRACER)
147 extern void stop_critical_timings(void);
148 extern void start_critical_timings(void);
149#else
150# define stop_critical_timings() do { } while (0)
151# define start_critical_timings() do { } while (0)
152#endif
153
154#ifdef CONFIG_DEBUG_IRQFLAGS
155extern void warn_bogus_irq_restore(void);
156#define raw_check_bogus_irq_restore() \
157 do { \
158 if (unlikely(!arch_irqs_disabled())) \
159 warn_bogus_irq_restore(); \
160 } while (0)
161#else
162#define raw_check_bogus_irq_restore() do { } while (0)
163#endif
164
165/*
166 * Wrap the arch provided IRQ routines to provide appropriate checks.
167 */
168#define raw_local_irq_disable() arch_local_irq_disable()
169#define raw_local_irq_enable() arch_local_irq_enable()
170#define raw_local_irq_save(flags) \
171 do { \
172 typecheck(unsigned long, flags); \
173 flags = arch_local_irq_save(); \
174 } while (0)
175#define raw_local_irq_restore(flags) \
176 do { \
177 typecheck(unsigned long, flags); \
178 raw_check_bogus_irq_restore(); \
179 arch_local_irq_restore(flags); \
180 } while (0)
181#define raw_local_save_flags(flags) \
182 do { \
183 typecheck(unsigned long, flags); \
184 flags = arch_local_save_flags(); \
185 } while (0)
186#define raw_irqs_disabled_flags(flags) \
187 ({ \
188 typecheck(unsigned long, flags); \
189 arch_irqs_disabled_flags(flags); \
190 })
191#define raw_irqs_disabled() (arch_irqs_disabled())
192#define raw_safe_halt() arch_safe_halt()
193
194/*
195 * The local_irq_*() APIs are equal to the raw_local_irq*()
196 * if !TRACE_IRQFLAGS.
197 */
198#ifdef CONFIG_TRACE_IRQFLAGS
199
200#define local_irq_enable() \
201 do { \
202 trace_hardirqs_on(); \
203 raw_local_irq_enable(); \
204 } while (0)
205
206#define local_irq_disable() \
207 do { \
208 bool was_disabled = raw_irqs_disabled();\
209 raw_local_irq_disable(); \
210 if (!was_disabled) \
211 trace_hardirqs_off(); \
212 } while (0)
213
214#define local_irq_save(flags) \
215 do { \
216 raw_local_irq_save(flags); \
217 if (!raw_irqs_disabled_flags(flags)) \
218 trace_hardirqs_off(); \
219 } while (0)
220
221#define local_irq_restore(flags) \
222 do { \
223 if (!raw_irqs_disabled_flags(flags)) \
224 trace_hardirqs_on(); \
225 raw_local_irq_restore(flags); \
226 } while (0)
227
228#define safe_halt() \
229 do { \
230 trace_hardirqs_on(); \
231 raw_safe_halt(); \
232 } while (0)
233
234
235#else /* !CONFIG_TRACE_IRQFLAGS */
236
237#define local_irq_enable() do { raw_local_irq_enable(); } while (0)
238#define local_irq_disable() do { raw_local_irq_disable(); } while (0)
239#define local_irq_save(flags) do { raw_local_irq_save(flags); } while (0)
240#define local_irq_restore(flags) do { raw_local_irq_restore(flags); } while (0)
241#define safe_halt() do { raw_safe_halt(); } while (0)
242
243#endif /* CONFIG_TRACE_IRQFLAGS */
244
245#define local_save_flags(flags) raw_local_save_flags(flags)
246
247/*
248 * Some architectures don't define arch_irqs_disabled(), so even if either
249 * definition would be fine we need to use different ones for the time being
250 * to avoid build issues.
251 */
252#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
253#define irqs_disabled() \
254 ({ \
255 unsigned long _flags; \
256 raw_local_save_flags(_flags); \
257 raw_irqs_disabled_flags(_flags); \
258 })
259#else /* !CONFIG_TRACE_IRQFLAGS_SUPPORT */
260#define irqs_disabled() raw_irqs_disabled()
261#endif /* CONFIG_TRACE_IRQFLAGS_SUPPORT */
262
263#define irqs_disabled_flags(flags) raw_irqs_disabled_flags(flags)
264
265DEFINE_LOCK_GUARD_0(irq, local_irq_disable(), local_irq_enable())
266DEFINE_LOCK_GUARD_0(irqsave,
267 local_irq_save(_T->flags),
268 local_irq_restore(_T->flags),
269 unsigned long flags)
270
271#endif
272