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