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