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/typecheck.h>
16#include <linux/cleanup.h>
17#include <asm/irqflags.h>
18#include <asm/percpu.h>
19
20/* Currently lockdep_softirqs_on/off is used only by lockdep */
21#ifdef CONFIG_PROVE_LOCKING
22 extern void lockdep_softirqs_on(unsigned long ip);
23 extern void lockdep_softirqs_off(unsigned long ip);
24 extern void lockdep_hardirqs_on_prepare(void);
25 extern void lockdep_hardirqs_on(unsigned long ip);
26 extern void lockdep_hardirqs_off(unsigned long ip);
27#else
28 static inline void lockdep_softirqs_on(unsigned long ip) { }
29 static inline void lockdep_softirqs_off(unsigned long ip) { }
30 static inline void lockdep_hardirqs_on_prepare(void) { }
31 static inline void lockdep_hardirqs_on(unsigned long ip) { }
32 static inline void lockdep_hardirqs_off(unsigned long ip) { }
33#endif
34
35#ifdef CONFIG_TRACE_IRQFLAGS
36
37/* Per-task IRQ trace events information. */
38struct irqtrace_events {
39 unsigned int irq_events;
40 unsigned long hardirq_enable_ip;
41 unsigned long hardirq_disable_ip;
42 unsigned int hardirq_enable_event;
43 unsigned int hardirq_disable_event;
44 unsigned long softirq_disable_ip;
45 unsigned long softirq_enable_ip;
46 unsigned int softirq_disable_event;
47 unsigned int softirq_enable_event;
48};
49
50DECLARE_PER_CPU(int, hardirqs_enabled);
51DECLARE_PER_CPU(int, hardirq_context);
52
53extern void trace_hardirqs_on_prepare(void);
54extern void trace_hardirqs_off_finish(void);
55extern void trace_hardirqs_on(void);
56extern void trace_hardirqs_off(void);
57
58# define lockdep_hardirq_context() (raw_cpu_read(hardirq_context))
59# define lockdep_softirq_context(p) ((p)->softirq_context)
60# define lockdep_hardirqs_enabled() (this_cpu_read(hardirqs_enabled))
61# define lockdep_softirqs_enabled(p) ((p)->softirqs_enabled)
62# define lockdep_hardirq_enter() \
63do { \
64 if (__this_cpu_inc_return(hardirq_context) == 1)\
65 current->hardirq_threaded = 0; \
66} while (0)
67# define lockdep_hardirq_threaded() \
68do { \
69 current->hardirq_threaded = 1; \
70} while (0)
71# define lockdep_hardirq_exit() \
72do { \
73 __this_cpu_dec(hardirq_context); \
74} while (0)
75
76# define lockdep_hrtimer_enter(__hrtimer) \
77({ \
78 bool __expires_hardirq = true; \
79 \
80 if (!__hrtimer->is_hard) { \
81 current->irq_config = 1; \
82 __expires_hardirq = false; \
83 } \
84 __expires_hardirq; \
85})
86
87# define lockdep_hrtimer_exit(__expires_hardirq) \
88 do { \
89 if (!__expires_hardirq) \
90 current->irq_config = 0; \
91 } while (0)
92
93# define lockdep_posixtimer_enter() \
94 do { \
95 current->irq_config = 1; \
96 } while (0)
97
98# define lockdep_posixtimer_exit() \
99 do { \
100 current->irq_config = 0; \
101 } while (0)
102
103# define lockdep_irq_work_enter(_flags) \
104 do { \
105 if (!((_flags) & IRQ_WORK_HARD_IRQ)) \
106 current->irq_config = 1; \
107 } while (0)
108# define lockdep_irq_work_exit(_flags) \
109 do { \
110 if (!((_flags) & IRQ_WORK_HARD_IRQ)) \
111 current->irq_config = 0; \
112 } while (0)
113
114#else
115# define trace_hardirqs_on_prepare() do { } while (0)
116# define trace_hardirqs_off_finish() do { } while (0)
117# define trace_hardirqs_on() do { } while (0)
118# define trace_hardirqs_off() do { } while (0)
119# define lockdep_hardirq_context() 0
120# define lockdep_softirq_context(p) 0
121# define lockdep_hardirqs_enabled() 0
122# define lockdep_softirqs_enabled(p) 0
123# define lockdep_hardirq_enter() do { } while (0)
124# define lockdep_hardirq_threaded() do { } while (0)
125# define lockdep_hardirq_exit() do { } while (0)
126# define lockdep_softirq_enter() do { } while (0)
127# define lockdep_softirq_exit() do { } while (0)
128# define lockdep_hrtimer_enter(__hrtimer) false
129# define lockdep_hrtimer_exit(__context) do { } while (0)
130# define lockdep_posixtimer_enter() do { } while (0)
131# define lockdep_posixtimer_exit() do { } while (0)
132# define lockdep_irq_work_enter(__work) do { } while (0)
133# define lockdep_irq_work_exit(__work) do { } while (0)
134#endif
135
136#if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT)
137# define lockdep_softirq_enter() \
138do { \
139 current->softirq_context++; \
140} while (0)
141# define lockdep_softirq_exit() \
142do { \
143 current->softirq_context--; \
144} while (0)
145
146#else
147# define lockdep_softirq_enter() do { } while (0)
148# define lockdep_softirq_exit() do { } while (0)
149#endif
150
151#if defined(CONFIG_IRQSOFF_TRACER) || \
152 defined(CONFIG_PREEMPT_TRACER)
153 extern void stop_critical_timings(void);
154 extern void start_critical_timings(void);
155#else
156# define stop_critical_timings() do { } while (0)
157# define start_critical_timings() do { } while (0)
158#endif
159
160#ifdef CONFIG_DEBUG_IRQFLAGS
161extern void warn_bogus_irq_restore(void);
162#define raw_check_bogus_irq_restore() \
163 do { \
164 if (unlikely(!arch_irqs_disabled())) \
165 warn_bogus_irq_restore(); \
166 } while (0)
167#else
168#define raw_check_bogus_irq_restore() do { } while (0)
169#endif
170
171/*
172 * Wrap the arch provided IRQ routines to provide appropriate checks.
173 */
174#define raw_local_irq_disable() arch_local_irq_disable()
175#define raw_local_irq_enable() arch_local_irq_enable()
176#define raw_local_irq_save(flags) \
177 do { \
178 typecheck(unsigned long, flags); \
179 flags = arch_local_irq_save(); \
180 } while (0)
181#define raw_local_irq_restore(flags) \
182 do { \
183 typecheck(unsigned long, flags); \
184 raw_check_bogus_irq_restore(); \
185 arch_local_irq_restore(flags); \
186 } while (0)
187#define raw_local_save_flags(flags) \
188 do { \
189 typecheck(unsigned long, flags); \
190 flags = arch_local_save_flags(); \
191 } while (0)
192#define raw_irqs_disabled_flags(flags) \
193 ({ \
194 typecheck(unsigned long, flags); \
195 arch_irqs_disabled_flags(flags); \
196 })
197#define raw_irqs_disabled() (arch_irqs_disabled())
198#define raw_safe_halt() arch_safe_halt()
199
200/*
201 * The local_irq_*() APIs are equal to the raw_local_irq*()
202 * if !TRACE_IRQFLAGS.
203 */
204#ifdef CONFIG_TRACE_IRQFLAGS
205
206#define local_irq_enable() \
207 do { \
208 trace_hardirqs_on(); \
209 raw_local_irq_enable(); \
210 } while (0)
211
212#define local_irq_disable() \
213 do { \
214 bool was_disabled = raw_irqs_disabled();\
215 raw_local_irq_disable(); \
216 if (!was_disabled) \
217 trace_hardirqs_off(); \
218 } while (0)
219
220#define local_irq_save(flags) \
221 do { \
222 raw_local_irq_save(flags); \
223 if (!raw_irqs_disabled_flags(flags)) \
224 trace_hardirqs_off(); \
225 } while (0)
226
227#define local_irq_restore(flags) \
228 do { \
229 if (!raw_irqs_disabled_flags(flags)) \
230 trace_hardirqs_on(); \
231 raw_local_irq_restore(flags); \
232 } while (0)
233
234#define safe_halt() \
235 do { \
236 trace_hardirqs_on(); \
237 raw_safe_halt(); \
238 } while (0)
239
240
241#else /* !CONFIG_TRACE_IRQFLAGS */
242
243#define local_irq_enable() do { raw_local_irq_enable(); } while (0)
244#define local_irq_disable() do { raw_local_irq_disable(); } while (0)
245#define local_irq_save(flags) do { raw_local_irq_save(flags); } while (0)
246#define local_irq_restore(flags) do { raw_local_irq_restore(flags); } while (0)
247#define safe_halt() do { raw_safe_halt(); } while (0)
248
249#endif /* CONFIG_TRACE_IRQFLAGS */
250
251#define local_save_flags(flags) raw_local_save_flags(flags)
252
253/*
254 * Some architectures don't define arch_irqs_disabled(), so even if either
255 * definition would be fine we need to use different ones for the time being
256 * to avoid build issues.
257 */
258#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
259#define irqs_disabled() \
260 ({ \
261 unsigned long _flags; \
262 raw_local_save_flags(_flags); \
263 raw_irqs_disabled_flags(_flags); \
264 })
265#else /* !CONFIG_TRACE_IRQFLAGS_SUPPORT */
266#define irqs_disabled() raw_irqs_disabled()
267#endif /* CONFIG_TRACE_IRQFLAGS_SUPPORT */
268
269#define irqs_disabled_flags(flags) raw_irqs_disabled_flags(flags)
270
271DEFINE_LOCK_GUARD_0(irq, local_irq_disable(), local_irq_enable())
272DEFINE_LOCK_GUARD_0(irqsave,
273 local_irq_save(_T->flags),
274 local_irq_restore(_T->flags),
275 unsigned long flags)
276
277#endif
278

source code of linux/include/linux/irqflags.h