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 struct task_struct;
  22
  23 /* Currently lockdep_softirqs_on/off is used only by lockdep */
  24 #ifdef CONFIG_PROVE_LOCKING
  25   extern void lockdep_softirqs_on(unsigned long ip);
  26   extern void lockdep_softirqs_off(unsigned long ip);
  27   extern void lockdep_hardirqs_on_prepare(void);
  28   extern void lockdep_hardirqs_on(unsigned long ip);
  29   extern void lockdep_hardirqs_off(unsigned long ip);
  30   extern void lockdep_cleanup_dead_cpu(unsigned int cpu,
  31                                        struct task_struct *idle);
  32 #else
  33   static inline void lockdep_softirqs_on(unsigned long ip) { }
  34   static inline void lockdep_softirqs_off(unsigned long ip) { }
  35   static inline void lockdep_hardirqs_on_prepare(void) { }
  36   static inline void lockdep_hardirqs_on(unsigned long ip) { }
  37   static inline void lockdep_hardirqs_off(unsigned long ip) { }
  38   static inline void lockdep_cleanup_dead_cpu(unsigned int cpu,
  39                                               struct task_struct *idle) {}
  40 #endif
  41
  42 #ifdef CONFIG_TRACE_IRQFLAGS
  43
  44 DECLARE_PER_CPU(int, hardirqs_enabled);
  45 DECLARE_PER_CPU(int, hardirq_context);
  46
  47 extern void trace_hardirqs_on_prepare(void);
  48 extern void trace_hardirqs_off_finish(void);
  49 extern void trace_hardirqs_on(void);
  50 extern void trace_hardirqs_off(void);
  51
  52 # define lockdep_hardirq_context()      (raw_cpu_read(hardirq_context))
  53 # define lockdep_softirq_context(p)     ((p)->softirq_context)
  54 # define lockdep_hardirqs_enabled()     (this_cpu_read(hardirqs_enabled))
  55 # define lockdep_softirqs_enabled(p)    ((p)->softirqs_enabled)
  56 # define lockdep_hardirq_enter()                        \
  57 do {                                                    \
  58         if (__this_cpu_inc_return(hardirq_context) == 1)\
  59                 current->hardirq_threaded = 0;          \
  60 } while (0)
  61 # define lockdep_hardirq_threaded()             \
  62 do {                                            \
  63         current->hardirq_threaded = 1;          \
  64 } while (0)
  65 # define lockdep_hardirq_exit()                 \
  66 do {                                            \
  67         __this_cpu_dec(hardirq_context);        \
  68 } while (0)
  69
  70 # define lockdep_hrtimer_enter(__hrtimer)               \
  71 ({                                                      \
  72         bool __expires_hardirq = true;                  \
  73                                                         \
  74         if (!__hrtimer->is_hard) {                      \
  75                 current->irq_config = 1;                \
  76                 __expires_hardirq = false;              \
  77         }                                               \
  78         __expires_hardirq;                              \
  79 })
  80
  81 # define lockdep_hrtimer_exit(__expires_hardirq)        \
  82         do {                                            \
  83                 if (!__expires_hardirq)                 \
  84                         current->irq_config = 0;        \
  85         } while (0)
  86
  87 # define lockdep_posixtimer_enter()                             \
  88           do {                                                  \
  89                   current->irq_config = 1;                      \
  90           } while (0)
  91
  92 # define lockdep_posixtimer_exit()                              \
  93           do {                                                  \
  94                   current->irq_config = 0;                      \
  95           } while (0)
  96
  97 # define lockdep_irq_work_enter(_flags)                                 \
  98           do {                                                          \
  99                   if (!((_flags) & IRQ_WORK_HARD_IRQ))                  \
 100                         current->irq_config = 1;                        \
 101           } while (0)
 102 # define lockdep_irq_work_exit(_flags)                                  \
 103           do {                                                          \
 104                   if (!((_flags) & IRQ_WORK_HARD_IRQ))                  \
 105                         current->irq_config = 0;                        \
 106           } while (0)
 107
 108 #else
 109 # define trace_hardirqs_on_prepare()            do { } while (0)
 110 # define trace_hardirqs_off_finish()            do { } while (0)
 111 # define trace_hardirqs_on()                    do { } while (0)
 112 # define trace_hardirqs_off()                   do { } while (0)
 113 # define lockdep_hardirq_context()              0
 114 # define lockdep_softirq_context(p)             0
 115 # define lockdep_hardirqs_enabled()             0
 116 # define lockdep_softirqs_enabled(p)            0
 117 # define lockdep_hardirq_enter()                do { } while (0)
 118 # define lockdep_hardirq_threaded()             do { } while (0)
 119 # define lockdep_hardirq_exit()                 do { } while (0)
 120 # define lockdep_softirq_enter()                do { } while (0)
 121 # define lockdep_softirq_exit()                 do { } while (0)
 122 # define lockdep_hrtimer_enter(__hrtimer)       false
 123 # define lockdep_hrtimer_exit(__context)        do { (void)(__context); } while (0)
 124 # define lockdep_posixtimer_enter()             do { } while (0)
 125 # define lockdep_posixtimer_exit()              do { } while (0)
 126 # define lockdep_irq_work_enter(__work)         do { } while (0)
 127 # define lockdep_irq_work_exit(__work)          do { } while (0)
 128 #endif
 129
 130 #if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT)
 131 # define lockdep_softirq_enter()                \
 132 do {                                            \
 133         current->softirq_context++;             \
 134 } while (0)
 135 # define lockdep_softirq_exit()                 \
 136 do {                                            \
 137         current->softirq_context--;             \
 138 } while (0)
 139
 140 #else
 141 # define lockdep_softirq_enter()                do { } while (0)
 142 # define lockdep_softirq_exit()                 do { } while (0)
 143 #endif
 144
 145 #if defined(CONFIG_IRQSOFF_TRACER) || \
 146         defined(CONFIG_PREEMPT_TRACER)
 147  extern void stop_critical_timings(void);
 148  extern void start_critical_timings(void);
 149 #else
 150 # define stop_critical_timings() do { } while (0)
 151 # define start_critical_timings() do { } while (0)
 152 #endif
 153
 154 #ifdef CONFIG_DEBUG_IRQFLAGS
 155 extern void warn_bogus_irq_restore(void);
 156 #define raw_check_bogus_irq_restore()                   \
 157         do {                                            \
 158                 if (unlikely(!arch_irqs_disabled()))    \
 159                         warn_bogus_irq_restore();       \
 160         } while (0)
 161 #else
 162 #define raw_check_bogus_irq_restore() do { } while (0)
 163 #endif
 164
 165 /*
 166  * Wrap the arch provided IRQ routines to provide appropriate checks.
 167  */
 168 #define raw_local_irq_disable()         arch_local_irq_disable()
 169 #define raw_local_irq_enable()          arch_local_irq_enable()
 170 #define raw_local_irq_save(flags)                       \
 171         do {                                            \
 172                 typecheck(unsigned long, flags);        \
 173                 flags = arch_local_irq_save();          \
 174         } while (0)
 175 #define raw_local_irq_restore(flags)                    \
 176         do {                                            \
 177                 typecheck(unsigned long, flags);        \
 178                 raw_check_bogus_irq_restore();          \
 179                 arch_local_irq_restore(flags);          \
 180         } while (0)
 181 #define raw_local_save_flags(flags)                     \
 182         do {                                            \
 183                 typecheck(unsigned long, flags);        \
 184                 flags = arch_local_save_flags();        \
 185         } while (0)
 186 #define raw_irqs_disabled_flags(flags)                  \
 187         ({                                              \
 188                 typecheck(unsigned long, flags);        \
 189                 arch_irqs_disabled_flags(flags);        \
 190         })
 191 #define raw_irqs_disabled()             (arch_irqs_disabled())
 192 #define raw_safe_halt()                 arch_safe_halt()
 193
 194 /*
 195  * The local_irq_*() APIs are equal to the raw_local_irq*()
 196  * if !TRACE_IRQFLAGS.
 197  */
 198 #ifdef CONFIG_TRACE_IRQFLAGS
 199
 200 #define local_irq_enable()                              \
 201         do {                                            \
 202                 trace_hardirqs_on();                    \
 203                 raw_local_irq_enable();                 \
 204         } while (0)
 205
 206 #define local_irq_disable()                             \
 207         do {                                            \
 208                 bool was_disabled = raw_irqs_disabled();\
 209                 raw_local_irq_disable();                \
 210                 if (!was_disabled)                      \
 211                         trace_hardirqs_off();           \
 212         } while (0)
 213
 214 #define local_irq_save(flags)                           \
 215         do {                                            \
 216                 raw_local_irq_save(flags);              \
 217                 if (!raw_irqs_disabled_flags(flags))    \
 218                         trace_hardirqs_off();           \
 219         } while (0)
 220
 221 #define local_irq_restore(flags)                        \
 222         do {                                            \
 223                 if (!raw_irqs_disabled_flags(flags))    \
 224                         trace_hardirqs_on();            \
 225                 raw_local_irq_restore(flags);           \
 226         } while (0)
 227
 228 #define safe_halt()                             \
 229         do {                                    \
 230                 trace_hardirqs_on();            \
 231                 raw_safe_halt();                \
 232         } while (0)
 233
 234
 235 #else /* !CONFIG_TRACE_IRQFLAGS */
 236
 237 #define local_irq_enable()      do { raw_local_irq_enable(); } while (0)
 238 #define local_irq_disable()     do { raw_local_irq_disable(); } while (0)
 239 #define local_irq_save(flags)   do { raw_local_irq_save(flags); } while (0)
 240 #define local_irq_restore(flags) do { raw_local_irq_restore(flags); } while (0)
 241 #define safe_halt()             do { raw_safe_halt(); } while (0)
 242
 243 #endif /* CONFIG_TRACE_IRQFLAGS */
 244
 245 #define local_save_flags(flags) raw_local_save_flags(flags)
 246
 247 /*
 248  * Some architectures don't define arch_irqs_disabled(), so even if either
 249  * definition would be fine we need to use different ones for the time being
 250  * to avoid build issues.
 251  */
 252 #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
 253 #define irqs_disabled()                                 \
 254         ({                                              \
 255                 unsigned long _flags;                   \
 256                 raw_local_save_flags(_flags);           \
 257                 raw_irqs_disabled_flags(_flags);        \
 258         })
 259 #else /* !CONFIG_TRACE_IRQFLAGS_SUPPORT */
 260 #define irqs_disabled() raw_irqs_disabled()
 261 #endif /* CONFIG_TRACE_IRQFLAGS_SUPPORT */
 262
 263 #define irqs_disabled_flags(flags) raw_irqs_disabled_flags(flags)
 264
 265 DEFINE_LOCK_GUARD_0(irq, local_irq_disable(), local_irq_enable())
 266 DEFINE_LOCK_GUARD_0(irqsave,
 267                     local_irq_save(_T->flags),
 268                     local_irq_restore(_T->flags),
 269                     unsigned long flags)
 270
 271 #endif