linux/include/linux/irqflags.h
<<
>>
Prefs
   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()                  \
  39do {                                            \
  40        current->hardirq_context++;             \
  41} while (0)
  42# define trace_hardirq_exit()                   \
  43do {                                            \
  44        current->hardirq_context--;             \
  45} while (0)
  46# define lockdep_softirq_enter()                \
  47do {                                            \
  48        current->softirq_context++;             \
  49} while (0)
  50# define lockdep_softirq_exit()                 \
  51do {                                            \
  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
 172