include/linux/irqflags.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 /*
0003  * include/linux/irqflags.h
0004  *
0005  * IRQ flags tracing: follow the state of the hardirq and softirq flags and
0006  * provide callbacks for transitions between ON and OFF states.
0007  *
0008  * This file gets included from lowlevel asm headers too, to provide
0009  * wrapped versions of the local_irq_*() APIs, based on the
0010  * raw_local_irq_*() macros from the lowlevel headers.
0011  */
0012 #ifndef _LINUX_TRACE_IRQFLAGS_H
0013 #define _LINUX_TRACE_IRQFLAGS_H
0014
0015 #include <linux/typecheck.h>
0016 #include <asm/irqflags.h>
0017 #include <asm/percpu.h>
0018
0019 /* Currently lockdep_softirqs_on/off is used only by lockdep */
0020 #ifdef CONFIG_PROVE_LOCKING
0021   extern void lockdep_softirqs_on(unsigned long ip);
0022   extern void lockdep_softirqs_off(unsigned long ip);
0023   extern void lockdep_hardirqs_on_prepare(void);
0024   extern void lockdep_hardirqs_on(unsigned long ip);
0025   extern void lockdep_hardirqs_off(unsigned long ip);
0026 #else
0027   static inline void lockdep_softirqs_on(unsigned long ip) { }
0028   static inline void lockdep_softirqs_off(unsigned long ip) { }
0029   static inline void lockdep_hardirqs_on_prepare(void) { }
0030   static inline void lockdep_hardirqs_on(unsigned long ip) { }
0031   static inline void lockdep_hardirqs_off(unsigned long ip) { }
0032 #endif
0033
0034 #ifdef CONFIG_TRACE_IRQFLAGS
0035
0036 /* Per-task IRQ trace events information. */
0037 struct irqtrace_events {
0038     unsigned int    irq_events;
0039     unsigned long   hardirq_enable_ip;
0040     unsigned long   hardirq_disable_ip;
0041     unsigned int    hardirq_enable_event;
0042     unsigned int    hardirq_disable_event;
0043     unsigned long   softirq_disable_ip;
0044     unsigned long   softirq_enable_ip;
0045     unsigned int    softirq_disable_event;
0046     unsigned int    softirq_enable_event;
0047 };
0048
0049 DECLARE_PER_CPU(int, hardirqs_enabled);
0050 DECLARE_PER_CPU(int, hardirq_context);
0051
0052 extern void trace_hardirqs_on_prepare(void);
0053 extern void trace_hardirqs_off_finish(void);
0054 extern void trace_hardirqs_on(void);
0055 extern void trace_hardirqs_off(void);
0056
0057 # define lockdep_hardirq_context()  (raw_cpu_read(hardirq_context))
0058 # define lockdep_softirq_context(p) ((p)->softirq_context)
0059 # define lockdep_hardirqs_enabled() (this_cpu_read(hardirqs_enabled))
0060 # define lockdep_softirqs_enabled(p)    ((p)->softirqs_enabled)
0061 # define lockdep_hardirq_enter()            \
0062 do {                            \
0063     if (__this_cpu_inc_return(hardirq_context) == 1)\
0064         current->hardirq_threaded = 0;      \
0065 } while (0)
0066 # define lockdep_hardirq_threaded()     \
0067 do {                        \
0068     current->hardirq_threaded = 1;      \
0069 } while (0)
0070 # define lockdep_hardirq_exit()         \
0071 do {                        \
0072     __this_cpu_dec(hardirq_context);    \
0073 } while (0)
0074
0075 # define lockdep_hrtimer_enter(__hrtimer)       \
0076 ({                          \
0077     bool __expires_hardirq = true;          \
0078                             \
0079     if (!__hrtimer->is_hard) {          \
0080         current->irq_config = 1;        \
0081         __expires_hardirq = false;      \
0082     }                       \
0083     __expires_hardirq;              \
0084 })
0085
0086 # define lockdep_hrtimer_exit(__expires_hardirq)    \
0087     do {                        \
0088         if (!__expires_hardirq)         \
0089             current->irq_config = 0;    \
0090     } while (0)
0091
0092 # define lockdep_posixtimer_enter()             \
0093       do {                          \
0094           current->irq_config = 1;          \
0095       } while (0)
0096
0097 # define lockdep_posixtimer_exit()              \
0098       do {                          \
0099           current->irq_config = 0;          \
0100       } while (0)
0101
0102 # define lockdep_irq_work_enter(_flags)                 \
0103       do {                              \
0104           if (!((_flags) & IRQ_WORK_HARD_IRQ))          \
0105             current->irq_config = 1;            \
0106       } while (0)
0107 # define lockdep_irq_work_exit(_flags)                  \
0108       do {                              \
0109           if (!((_flags) & IRQ_WORK_HARD_IRQ))          \
0110             current->irq_config = 0;            \
0111       } while (0)
0112
0113 #else
0114 # define trace_hardirqs_on_prepare()        do { } while (0)
0115 # define trace_hardirqs_off_finish()        do { } while (0)
0116 # define trace_hardirqs_on()            do { } while (0)
0117 # define trace_hardirqs_off()           do { } while (0)
0118 # define lockdep_hardirq_context()      0
0119 # define lockdep_softirq_context(p)     0
0120 # define lockdep_hardirqs_enabled()     0
0121 # define lockdep_softirqs_enabled(p)        0
0122 # define lockdep_hardirq_enter()        do { } while (0)
0123 # define lockdep_hardirq_threaded()     do { } while (0)
0124 # define lockdep_hardirq_exit()         do { } while (0)
0125 # define lockdep_softirq_enter()        do { } while (0)
0126 # define lockdep_softirq_exit()         do { } while (0)
0127 # define lockdep_hrtimer_enter(__hrtimer)   false
0128 # define lockdep_hrtimer_exit(__context)    do { } while (0)
0129 # define lockdep_posixtimer_enter()     do { } while (0)
0130 # define lockdep_posixtimer_exit()      do { } while (0)
0131 # define lockdep_irq_work_enter(__work)     do { } while (0)
0132 # define lockdep_irq_work_exit(__work)      do { } while (0)
0133 #endif
0134
0135 #if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT)
0136 # define lockdep_softirq_enter()        \
0137 do {                        \
0138     current->softirq_context++;     \
0139 } while (0)
0140 # define lockdep_softirq_exit()         \
0141 do {                        \
0142     current->softirq_context--;     \
0143 } while (0)
0144
0145 #else
0146 # define lockdep_softirq_enter()        do { } while (0)
0147 # define lockdep_softirq_exit()         do { } while (0)
0148 #endif
0149
0150 #if defined(CONFIG_IRQSOFF_TRACER) || \
0151     defined(CONFIG_PREEMPT_TRACER)
0152  extern void stop_critical_timings(void);
0153  extern void start_critical_timings(void);
0154 #else
0155 # define stop_critical_timings() do { } while (0)
0156 # define start_critical_timings() do { } while (0)
0157 #endif
0158
0159 #ifdef CONFIG_DEBUG_IRQFLAGS
0160 extern void warn_bogus_irq_restore(void);
0161 #define raw_check_bogus_irq_restore()           \
0162     do {                        \
0163         if (unlikely(!arch_irqs_disabled()))    \
0164             warn_bogus_irq_restore();   \
0165     } while (0)
0166 #else
0167 #define raw_check_bogus_irq_restore() do { } while (0)
0168 #endif
0169
0170 /*
0171  * Wrap the arch provided IRQ routines to provide appropriate checks.
0172  */
0173 #define raw_local_irq_disable()     arch_local_irq_disable()
0174 #define raw_local_irq_enable()      arch_local_irq_enable()
0175 #define raw_local_irq_save(flags)           \
0176     do {                        \
0177         typecheck(unsigned long, flags);    \
0178         flags = arch_local_irq_save();      \
0179     } while (0)
0180 #define raw_local_irq_restore(flags)            \
0181     do {                        \
0182         typecheck(unsigned long, flags);    \
0183         raw_check_bogus_irq_restore();      \
0184         arch_local_irq_restore(flags);      \
0185     } while (0)
0186 #define raw_local_save_flags(flags)         \
0187     do {                        \
0188         typecheck(unsigned long, flags);    \
0189         flags = arch_local_save_flags();    \
0190     } while (0)
0191 #define raw_irqs_disabled_flags(flags)          \
0192     ({                      \
0193         typecheck(unsigned long, flags);    \
0194         arch_irqs_disabled_flags(flags);    \
0195     })
0196 #define raw_irqs_disabled()     (arch_irqs_disabled())
0197 #define raw_safe_halt()         arch_safe_halt()
0198
0199 /*
0200  * The local_irq_*() APIs are equal to the raw_local_irq*()
0201  * if !TRACE_IRQFLAGS.
0202  */
0203 #ifdef CONFIG_TRACE_IRQFLAGS
0204
0205 #define local_irq_enable()              \
0206     do {                        \
0207         trace_hardirqs_on();            \
0208         raw_local_irq_enable();         \
0209     } while (0)
0210
0211 #define local_irq_disable()             \
0212     do {                        \
0213         bool was_disabled = raw_irqs_disabled();\
0214         raw_local_irq_disable();        \
0215         if (!was_disabled)          \
0216             trace_hardirqs_off();       \
0217     } while (0)
0218
0219 #define local_irq_save(flags)               \
0220     do {                        \
0221         raw_local_irq_save(flags);      \
0222         if (!raw_irqs_disabled_flags(flags))    \
0223             trace_hardirqs_off();       \
0224     } while (0)
0225
0226 #define local_irq_restore(flags)            \
0227     do {                        \
0228         if (!raw_irqs_disabled_flags(flags))    \
0229             trace_hardirqs_on();        \
0230         raw_local_irq_restore(flags);       \
0231     } while (0)
0232
0233 #define safe_halt()             \
0234     do {                    \
0235         trace_hardirqs_on();        \
0236         raw_safe_halt();        \
0237     } while (0)
0238
0239
0240 #else /* !CONFIG_TRACE_IRQFLAGS */
0241
0242 #define local_irq_enable()  do { raw_local_irq_enable(); } while (0)
0243 #define local_irq_disable() do { raw_local_irq_disable(); } while (0)
0244 #define local_irq_save(flags)   do { raw_local_irq_save(flags); } while (0)
0245 #define local_irq_restore(flags) do { raw_local_irq_restore(flags); } while (0)
0246 #define safe_halt()     do { raw_safe_halt(); } while (0)
0247
0248 #endif /* CONFIG_TRACE_IRQFLAGS */
0249
0250 #define local_save_flags(flags) raw_local_save_flags(flags)
0251
0252 /*
0253  * Some architectures don't define arch_irqs_disabled(), so even if either
0254  * definition would be fine we need to use different ones for the time being
0255  * to avoid build issues.
0256  */
0257 #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
0258 #define irqs_disabled()                 \
0259     ({                      \
0260         unsigned long _flags;           \
0261         raw_local_save_flags(_flags);       \
0262         raw_irqs_disabled_flags(_flags);    \
0263     })
0264 #else /* !CONFIG_TRACE_IRQFLAGS_SUPPORT */
0265 #define irqs_disabled() raw_irqs_disabled()
0266 #endif /* CONFIG_TRACE_IRQFLAGS_SUPPORT */
0267
0268 #define irqs_disabled_flags(flags) raw_irqs_disabled_flags(flags)
0269
0270 #endif