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