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
  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()                        \
  62 do {                                                    \
  63         if (__this_cpu_inc_return(hardirq_context) == 1)\
  64                 current->hardirq_threaded = 0;          \
  65 } while (0)
  66 # define lockdep_hardirq_threaded()             \
  67 do {                                            \
  68         current->hardirq_threaded = 1;          \
  69 } while (0)
  70 # define lockdep_hardirq_exit()                 \
  71 do {                                            \
  72         __this_cpu_dec(hardirq_context);        \
  73 } while (0)
  74 # define lockdep_softirq_enter()                \
  75 do {                                            \
  76         current->softirq_context++;             \
  77 } while (0)
  78 # define lockdep_softirq_exit()                 \
  79 do {                                            \
  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
 153 extern 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