include/linux/irqflags.h

   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 <asm/irqflags.h>
  17
  18 /* Currently trace_softirqs_on/off is used only by lockdep */
  19 #ifdef CONFIG_PROVE_LOCKING
  20   extern void trace_softirqs_on(unsigned long ip);
  21   extern void trace_softirqs_off(unsigned long ip);
  22   extern void lockdep_hardirqs_on(unsigned long ip);
  23   extern void lockdep_hardirqs_off(unsigned long ip);
  24 #else
  25   static inline void trace_softirqs_on(unsigned long ip) { }
  26   static inline void trace_softirqs_off(unsigned long ip) { }
  27   static inline void lockdep_hardirqs_on(unsigned long ip) { }
  28   static inline void lockdep_hardirqs_off(unsigned long ip) { }
  29 #endif
  30
  31 #ifdef CONFIG_TRACE_IRQFLAGS
  32   extern void trace_hardirqs_on(void);
  33   extern void trace_hardirqs_off(void);
  34 # define trace_hardirq_context(p)       ((p)->hardirq_context)
  35 # define trace_softirq_context(p)       ((p)->softirq_context)
  36 # define trace_hardirqs_enabled(p)      ((p)->hardirqs_enabled)
  37 # define trace_softirqs_enabled(p)      ((p)->softirqs_enabled)
  38 # define trace_hardirq_enter()                  \
  39 do {                                            \
  40         current->hardirq_context++;             \
  41 } while (0)
  42 # define trace_hardirq_exit()                   \
  43 do {                                            \
  44         current->hardirq_context--;             \
  45 } while (0)
  46 # define lockdep_softirq_enter()                \
  47 do {                                            \
  48         current->softirq_context++;             \
  49 } while (0)
  50 # define lockdep_softirq_exit()                 \
  51 do {                                            \
  52         current->softirq_context--;             \
  53 } while (0)
  54 #else
  55 # define trace_hardirqs_on()            do { } while (0)
  56 # define trace_hardirqs_off()           do { } while (0)
  57 # define trace_hardirq_context(p)       0
  58 # define trace_softirq_context(p)       0
  59 # define trace_hardirqs_enabled(p)      0
  60 # define trace_softirqs_enabled(p)      0
  61 # define trace_hardirq_enter()          do { } while (0)
  62 # define trace_hardirq_exit()           do { } while (0)
  63 # define lockdep_softirq_enter()        do { } while (0)
  64 # define lockdep_softirq_exit()         do { } while (0)
  65 #endif
  66
  67 #if defined(CONFIG_IRQSOFF_TRACER) || \
  68         defined(CONFIG_PREEMPT_TRACER)
  69  extern void stop_critical_timings(void);
  70  extern void start_critical_timings(void);
  71 #else
  72 # define stop_critical_timings() do { } while (0)
  73 # define start_critical_timings() do { } while (0)
  74 #endif
  75
  76 /*
  77  * Wrap the arch provided IRQ routines to provide appropriate checks.
  78  */
  79 #define raw_local_irq_disable()         arch_local_irq_disable()
  80 #define raw_local_irq_enable()          arch_local_irq_enable()
  81 #define raw_local_irq_save(flags)                       \
  82         do {                                            \
  83                 typecheck(unsigned long, flags);        \
  84                 flags = arch_local_irq_save();          \
  85         } while (0)
  86 #define raw_local_irq_restore(flags)                    \
  87         do {                                            \
  88                 typecheck(unsigned long, flags);        \
  89                 arch_local_irq_restore(flags);          \
  90         } while (0)
  91 #define raw_local_save_flags(flags)                     \
  92         do {                                            \
  93                 typecheck(unsigned long, flags);        \
  94                 flags = arch_local_save_flags();        \
  95         } while (0)
  96 #define raw_irqs_disabled_flags(flags)                  \
  97         ({                                              \
  98                 typecheck(unsigned long, flags);        \
  99                 arch_irqs_disabled_flags(flags);        \
 100         })
 101 #define raw_irqs_disabled()             (arch_irqs_disabled())
 102 #define raw_safe_halt()                 arch_safe_halt()
 103
 104 /*
 105  * The local_irq_*() APIs are equal to the raw_local_irq*()
 106  * if !TRACE_IRQFLAGS.
 107  */
 108 #ifdef CONFIG_TRACE_IRQFLAGS
 109 #define local_irq_enable() \
 110         do { trace_hardirqs_on(); raw_local_irq_enable(); } while (0)
 111 #define local_irq_disable() \
 112         do { raw_local_irq_disable(); trace_hardirqs_off(); } while (0)
 113 #define local_irq_save(flags)                           \
 114         do {                                            \
 115                 raw_local_irq_save(flags);              \
 116                 trace_hardirqs_off();                   \
 117         } while (0)
 118
 119
 120 #define local_irq_restore(flags)                        \
 121         do {                                            \
 122                 if (raw_irqs_disabled_flags(flags)) {   \
 123                         raw_local_irq_restore(flags);   \
 124                         trace_hardirqs_off();           \
 125                 } else {                                \
 126                         trace_hardirqs_on();            \
 127                         raw_local_irq_restore(flags);   \
 128                 }                                       \
 129         } while (0)
 130
 131 #define safe_halt()                             \
 132         do {                                    \
 133                 trace_hardirqs_on();            \
 134                 raw_safe_halt();                \
 135         } while (0)
 136
 137
 138 #else /* !CONFIG_TRACE_IRQFLAGS */
 139
 140 #define local_irq_enable()      do { raw_local_irq_enable(); } while (0)
 141 #define local_irq_disable()     do { raw_local_irq_disable(); } while (0)
 142 #define local_irq_save(flags)                                   \
 143         do {                                                    \
 144                 raw_local_irq_save(flags);                      \
 145         } while (0)
 146 #define local_irq_restore(flags) do { raw_local_irq_restore(flags); } while (0)
 147 #define safe_halt()             do { raw_safe_halt(); } while (0)
 148
 149 #endif /* CONFIG_TRACE_IRQFLAGS */
 150
 151 #define local_save_flags(flags) raw_local_save_flags(flags)
 152
 153 /*
 154  * Some architectures don't define arch_irqs_disabled(), so even if either
 155  * definition would be fine we need to use different ones for the time being
 156  * to avoid build issues.
 157  */
 158 #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
 159 #define irqs_disabled()                                 \
 160         ({                                              \
 161                 unsigned long _flags;                   \
 162                 raw_local_save_flags(_flags);           \
 163                 raw_irqs_disabled_flags(_flags);        \
 164         })
 165 #else /* !CONFIG_TRACE_IRQFLAGS_SUPPORT */
 166 #define irqs_disabled() raw_irqs_disabled()
 167 #endif /* CONFIG_TRACE_IRQFLAGS_SUPPORT */
 168
 169 #define irqs_disabled_flags(flags) raw_irqs_disabled_flags(flags)
 170
 171 #endif