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/irqflags_types.h>
  16 #include <linux/typecheck.h>
  17 #include <linux/cleanup.h>
  18 #include <asm/irqflags.h>
  19 #include <asm/percpu.h>
  20
  21 /* Currently lockdep_softirqs_on/off is used only by lockdep */
  22 #ifdef CONFIG_PROVE_LOCKING
  23   extern void lockdep_softirqs_on(unsigned long ip);
  24   extern void lockdep_softirqs_off(unsigned long ip);
  25   extern void lockdep_hardirqs_on_prepare(void);
  26   extern void lockdep_hardirqs_on(unsigned long ip);
  27   extern void lockdep_hardirqs_off(unsigned long ip);
  28 #else
  29   static inline void lockdep_softirqs_on(unsigned long ip) { }
  30   static inline void lockdep_softirqs_off(unsigned long ip) { }
  31   static inline void lockdep_hardirqs_on_prepare(void) { }
  32   static inline void lockdep_hardirqs_on(unsigned long ip) { }
  33   static inline void lockdep_hardirqs_off(unsigned long ip) { }
  34 #endif
  35
  36 #ifdef CONFIG_TRACE_IRQFLAGS
  37
  38 DECLARE_PER_CPU(int, hardirqs_enabled);
  39 DECLARE_PER_CPU(int, hardirq_context);
  40
  41 extern void trace_hardirqs_on_prepare(void);
  42 extern void trace_hardirqs_off_finish(void);
  43 extern void trace_hardirqs_on(void);
  44 extern void trace_hardirqs_off(void);
  45
  46 # define lockdep_hardirq_context()      (raw_cpu_read(hardirq_context))
  47 # define lockdep_softirq_context(p)     ((p)->softirq_context)
  48 # define lockdep_hardirqs_enabled()     (this_cpu_read(hardirqs_enabled))
  49 # define lockdep_softirqs_enabled(p)    ((p)->softirqs_enabled)
  50 # define lockdep_hardirq_enter()                        \
  51 do {                                                    \
  52         if (__this_cpu_inc_return(hardirq_context) == 1)\
  53                 current->hardirq_threaded = 0;          \
  54 } while (0)
  55 # define lockdep_hardirq_threaded()             \
  56 do {                                            \
  57         current->hardirq_threaded = 1;          \
  58 } while (0)
  59 # define lockdep_hardirq_exit()                 \
  60 do {                                            \
  61         __this_cpu_dec(hardirq_context);        \
  62 } while (0)
  63
  64 # define lockdep_hrtimer_enter(__hrtimer)               \
  65 ({                                                      \
  66         bool __expires_hardirq = true;                  \
  67                                                         \
  68         if (!__hrtimer->is_hard) {                      \
  69                 current->irq_config = 1;                \
  70                 __expires_hardirq = false;              \
  71         }                                               \
  72         __expires_hardirq;                              \
  73 })
  74
  75 # define lockdep_hrtimer_exit(__expires_hardirq)        \
  76         do {                                            \
  77                 if (!__expires_hardirq)                 \
  78                         current->irq_config = 0;        \
  79         } while (0)
  80
  81 # define lockdep_posixtimer_enter()                             \
  82           do {                                                  \
  83                   current->irq_config = 1;                      \
  84           } while (0)
  85
  86 # define lockdep_posixtimer_exit()                              \
  87           do {                                                  \
  88                   current->irq_config = 0;                      \
  89           } while (0)
  90
  91 # define lockdep_irq_work_enter(_flags)                                 \
  92           do {                                                          \
  93                   if (!((_flags) & IRQ_WORK_HARD_IRQ))                  \
  94                         current->irq_config = 1;                        \
  95           } while (0)
  96 # define lockdep_irq_work_exit(_flags)                                  \
  97           do {                                                          \
  98                   if (!((_flags) & IRQ_WORK_HARD_IRQ))                  \
  99                         current->irq_config = 0;                        \
 100           } while (0)
 101
 102 #else
 103 # define trace_hardirqs_on_prepare()            do { } while (0)
 104 # define trace_hardirqs_off_finish()            do { } while (0)
 105 # define trace_hardirqs_on()                    do { } while (0)
 106 # define trace_hardirqs_off()                   do { } while (0)
 107 # define lockdep_hardirq_context()              0
 108 # define lockdep_softirq_context(p)             0
 109 # define lockdep_hardirqs_enabled()             0
 110 # define lockdep_softirqs_enabled(p)            0
 111 # define lockdep_hardirq_enter()                do { } while (0)
 112 # define lockdep_hardirq_threaded()             do { } while (0)
 113 # define lockdep_hardirq_exit()                 do { } while (0)
 114 # define lockdep_softirq_enter()                do { } while (0)
 115 # define lockdep_softirq_exit()                 do { } while (0)
 116 # define lockdep_hrtimer_enter(__hrtimer)       false
 117 # define lockdep_hrtimer_exit(__context)        do { (void)(__context); } while (0)
 118 # define lockdep_posixtimer_enter()             do { } while (0)
 119 # define lockdep_posixtimer_exit()              do { } while (0)
 120 # define lockdep_irq_work_enter(__work)         do { } while (0)
 121 # define lockdep_irq_work_exit(__work)          do { } while (0)
 122 #endif
 123
 124 #if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT)
 125 # define lockdep_softirq_enter()                \
 126 do {                                            \
 127         current->softirq_context++;             \
 128 } while (0)
 129 # define lockdep_softirq_exit()                 \
 130 do {                                            \
 131         current->softirq_context--;             \
 132 } while (0)
 133
 134 #else
 135 # define lockdep_softirq_enter()                do { } while (0)
 136 # define lockdep_softirq_exit()                 do { } while (0)
 137 #endif
 138
 139 #if defined(CONFIG_IRQSOFF_TRACER) || \
 140         defined(CONFIG_PREEMPT_TRACER)
 141  extern void stop_critical_timings(void);
 142  extern void start_critical_timings(void);
 143 #else
 144 # define stop_critical_timings() do { } while (0)
 145 # define start_critical_timings() do { } while (0)
 146 #endif
 147
 148 #ifdef CONFIG_DEBUG_IRQFLAGS
 149 extern void warn_bogus_irq_restore(void);
 150 #define raw_check_bogus_irq_restore()                   \
 151         do {                                            \
 152                 if (unlikely(!arch_irqs_disabled()))    \
 153                         warn_bogus_irq_restore();       \
 154         } while (0)
 155 #else
 156 #define raw_check_bogus_irq_restore() do { } while (0)
 157 #endif
 158
 159 /*
 160  * Wrap the arch provided IRQ routines to provide appropriate checks.
 161  */
 162 #define raw_local_irq_disable()         arch_local_irq_disable()
 163 #define raw_local_irq_enable()          arch_local_irq_enable()
 164 #define raw_local_irq_save(flags)                       \
 165         do {                                            \
 166                 typecheck(unsigned long, flags);        \
 167                 flags = arch_local_irq_save();          \
 168         } while (0)
 169 #define raw_local_irq_restore(flags)                    \
 170         do {                                            \
 171                 typecheck(unsigned long, flags);        \
 172                 raw_check_bogus_irq_restore();          \
 173                 arch_local_irq_restore(flags);          \
 174         } while (0)
 175 #define raw_local_save_flags(flags)                     \
 176         do {                                            \
 177                 typecheck(unsigned long, flags);        \
 178                 flags = arch_local_save_flags();        \
 179         } while (0)
 180 #define raw_irqs_disabled_flags(flags)                  \
 181         ({                                              \
 182                 typecheck(unsigned long, flags);        \
 183                 arch_irqs_disabled_flags(flags);        \
 184         })
 185 #define raw_irqs_disabled()             (arch_irqs_disabled())
 186 #define raw_safe_halt()                 arch_safe_halt()
 187
 188 /*
 189  * The local_irq_*() APIs are equal to the raw_local_irq*()
 190  * if !TRACE_IRQFLAGS.
 191  */
 192 #ifdef CONFIG_TRACE_IRQFLAGS
 193
 194 #define local_irq_enable()                              \
 195         do {                                            \
 196                 trace_hardirqs_on();                    \
 197                 raw_local_irq_enable();                 \
 198         } while (0)
 199
 200 #define local_irq_disable()                             \
 201         do {                                            \
 202                 bool was_disabled = raw_irqs_disabled();\
 203                 raw_local_irq_disable();                \
 204                 if (!was_disabled)                      \
 205                         trace_hardirqs_off();           \
 206         } while (0)
 207
 208 #define local_irq_save(flags)                           \
 209         do {                                            \
 210                 raw_local_irq_save(flags);              \
 211                 if (!raw_irqs_disabled_flags(flags))    \
 212                         trace_hardirqs_off();           \
 213         } while (0)
 214
 215 #define local_irq_restore(flags)                        \
 216         do {                                            \
 217                 if (!raw_irqs_disabled_flags(flags))    \
 218                         trace_hardirqs_on();            \
 219                 raw_local_irq_restore(flags);           \
 220         } while (0)
 221
 222 #define safe_halt()                             \
 223         do {                                    \
 224                 trace_hardirqs_on();            \
 225                 raw_safe_halt();                \
 226         } while (0)
 227
 228
 229 #else /* !CONFIG_TRACE_IRQFLAGS */
 230
 231 #define local_irq_enable()      do { raw_local_irq_enable(); } while (0)
 232 #define local_irq_disable()     do { raw_local_irq_disable(); } while (0)
 233 #define local_irq_save(flags)   do { raw_local_irq_save(flags); } while (0)
 234 #define local_irq_restore(flags) do { raw_local_irq_restore(flags); } while (0)
 235 #define safe_halt()             do { raw_safe_halt(); } while (0)
 236
 237 #endif /* CONFIG_TRACE_IRQFLAGS */
 238
 239 #define local_save_flags(flags) raw_local_save_flags(flags)
 240
 241 /*
 242  * Some architectures don't define arch_irqs_disabled(), so even if either
 243  * definition would be fine we need to use different ones for the time being
 244  * to avoid build issues.
 245  */
 246 #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
 247 #define irqs_disabled()                                 \
 248         ({                                              \
 249                 unsigned long _flags;                   \
 250                 raw_local_save_flags(_flags);           \
 251                 raw_irqs_disabled_flags(_flags);        \
 252         })
 253 #else /* !CONFIG_TRACE_IRQFLAGS_SUPPORT */
 254 #define irqs_disabled() raw_irqs_disabled()
 255 #endif /* CONFIG_TRACE_IRQFLAGS_SUPPORT */
 256
 257 #define irqs_disabled_flags(flags) raw_irqs_disabled_flags(flags)
 258
 259 DEFINE_LOCK_GUARD_0(irq, local_irq_disable(), local_irq_enable())
 260 DEFINE_LOCK_GUARD_0(irqsave,
 261                     local_irq_save(_T->flags),
 262                     local_irq_restore(_T->flags),
 263                     unsigned long flags)
 264
 265 #endif