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 <linux/cleanup.h>
  17 #include <asm/irqflags.h>
  18 #include <asm/percpu.h>
  19
  20 /* Currently lockdep_softirqs_on/off is used only by lockdep */
  21 #ifdef CONFIG_PROVE_LOCKING
  22   extern void lockdep_softirqs_on(unsigned long ip);
  23   extern void lockdep_softirqs_off(unsigned long ip);
  24   extern void lockdep_hardirqs_on_prepare(void);
  25   extern void lockdep_hardirqs_on(unsigned long ip);
  26   extern void lockdep_hardirqs_off(unsigned long ip);
  27 #else
  28   static inline void lockdep_softirqs_on(unsigned long ip) { }
  29   static inline void lockdep_softirqs_off(unsigned long ip) { }
  30   static inline void lockdep_hardirqs_on_prepare(void) { }
  31   static inline void lockdep_hardirqs_on(unsigned long ip) { }
  32   static inline void lockdep_hardirqs_off(unsigned long ip) { }
  33 #endif
  34
  35 #ifdef CONFIG_TRACE_IRQFLAGS
  36
  37 /* Per-task IRQ trace events information. */
  38 struct irqtrace_events {
  39         unsigned int    irq_events;
  40         unsigned long   hardirq_enable_ip;
  41         unsigned long   hardirq_disable_ip;
  42         unsigned int    hardirq_enable_event;
  43         unsigned int    hardirq_disable_event;
  44         unsigned long   softirq_disable_ip;
  45         unsigned long   softirq_enable_ip;
  46         unsigned int    softirq_disable_event;
  47         unsigned int    softirq_enable_event;
  48 };
  49
  50 DECLARE_PER_CPU(int, hardirqs_enabled);
  51 DECLARE_PER_CPU(int, hardirq_context);
  52
  53 extern void trace_hardirqs_on_prepare(void);
  54 extern void trace_hardirqs_off_finish(void);
  55 extern void trace_hardirqs_on(void);
  56 extern void trace_hardirqs_off(void);
  57
  58 # define lockdep_hardirq_context()      (raw_cpu_read(hardirq_context))
  59 # define lockdep_softirq_context(p)     ((p)->softirq_context)
  60 # define lockdep_hardirqs_enabled()     (this_cpu_read(hardirqs_enabled))
  61 # define lockdep_softirqs_enabled(p)    ((p)->softirqs_enabled)
  62 # define lockdep_hardirq_enter()                        \
  63 do {                                                    \
  64         if (__this_cpu_inc_return(hardirq_context) == 1)\
  65                 current->hardirq_threaded = 0;          \
  66 } while (0)
  67 # define lockdep_hardirq_threaded()             \
  68 do {                                            \
  69         current->hardirq_threaded = 1;          \
  70 } while (0)
  71 # define lockdep_hardirq_exit()                 \
  72 do {                                            \
  73         __this_cpu_dec(hardirq_context);        \
  74 } while (0)
  75
  76 # define lockdep_hrtimer_enter(__hrtimer)               \
  77 ({                                                      \
  78         bool __expires_hardirq = true;                  \
  79                                                         \
  80         if (!__hrtimer->is_hard) {                      \
  81                 current->irq_config = 1;                \
  82                 __expires_hardirq = false;              \
  83         }                                               \
  84         __expires_hardirq;                              \
  85 })
  86
  87 # define lockdep_hrtimer_exit(__expires_hardirq)        \
  88         do {                                            \
  89                 if (!__expires_hardirq)                 \
  90                         current->irq_config = 0;        \
  91         } while (0)
  92
  93 # define lockdep_posixtimer_enter()                             \
  94           do {                                                  \
  95                   current->irq_config = 1;                      \
  96           } while (0)
  97
  98 # define lockdep_posixtimer_exit()                              \
  99           do {                                                  \
 100                   current->irq_config = 0;                      \
 101           } while (0)
 102
 103 # define lockdep_irq_work_enter(_flags)                                 \
 104           do {                                                          \
 105                   if (!((_flags) & IRQ_WORK_HARD_IRQ))                  \
 106                         current->irq_config = 1;                        \
 107           } while (0)
 108 # define lockdep_irq_work_exit(_flags)                                  \
 109           do {                                                          \
 110                   if (!((_flags) & IRQ_WORK_HARD_IRQ))                  \
 111                         current->irq_config = 0;                        \
 112           } while (0)
 113
 114 #else
 115 # define trace_hardirqs_on_prepare()            do { } while (0)
 116 # define trace_hardirqs_off_finish()            do { } while (0)
 117 # define trace_hardirqs_on()                    do { } while (0)
 118 # define trace_hardirqs_off()                   do { } while (0)
 119 # define lockdep_hardirq_context()              0
 120 # define lockdep_softirq_context(p)             0
 121 # define lockdep_hardirqs_enabled()             0
 122 # define lockdep_softirqs_enabled(p)            0
 123 # define lockdep_hardirq_enter()                do { } while (0)
 124 # define lockdep_hardirq_threaded()             do { } while (0)
 125 # define lockdep_hardirq_exit()                 do { } while (0)
 126 # define lockdep_softirq_enter()                do { } while (0)
 127 # define lockdep_softirq_exit()                 do { } while (0)
 128 # define lockdep_hrtimer_enter(__hrtimer)       false
 129 # define lockdep_hrtimer_exit(__context)        do { } while (0)
 130 # define lockdep_posixtimer_enter()             do { } while (0)
 131 # define lockdep_posixtimer_exit()              do { } while (0)
 132 # define lockdep_irq_work_enter(__work)         do { } while (0)
 133 # define lockdep_irq_work_exit(__work)          do { } while (0)
 134 #endif
 135
 136 #if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT)
 137 # define lockdep_softirq_enter()                \
 138 do {                                            \
 139         current->softirq_context++;             \
 140 } while (0)
 141 # define lockdep_softirq_exit()                 \
 142 do {                                            \
 143         current->softirq_context--;             \
 144 } while (0)
 145
 146 #else
 147 # define lockdep_softirq_enter()                do { } while (0)
 148 # define lockdep_softirq_exit()                 do { } while (0)
 149 #endif
 150
 151 #if defined(CONFIG_IRQSOFF_TRACER) || \
 152         defined(CONFIG_PREEMPT_TRACER)
 153  extern void stop_critical_timings(void);
 154  extern void start_critical_timings(void);
 155 #else
 156 # define stop_critical_timings() do { } while (0)
 157 # define start_critical_timings() do { } while (0)
 158 #endif
 159
 160 #ifdef CONFIG_DEBUG_IRQFLAGS
 161 extern void warn_bogus_irq_restore(void);
 162 #define raw_check_bogus_irq_restore()                   \
 163         do {                                            \
 164                 if (unlikely(!arch_irqs_disabled()))    \
 165                         warn_bogus_irq_restore();       \
 166         } while (0)
 167 #else
 168 #define raw_check_bogus_irq_restore() do { } while (0)
 169 #endif
 170
 171 /*
 172  * Wrap the arch provided IRQ routines to provide appropriate checks.
 173  */
 174 #define raw_local_irq_disable()         arch_local_irq_disable()
 175 #define raw_local_irq_enable()          arch_local_irq_enable()
 176 #define raw_local_irq_save(flags)                       \
 177         do {                                            \
 178                 typecheck(unsigned long, flags);        \
 179                 flags = arch_local_irq_save();          \
 180         } while (0)
 181 #define raw_local_irq_restore(flags)                    \
 182         do {                                            \
 183                 typecheck(unsigned long, flags);        \
 184                 raw_check_bogus_irq_restore();          \
 185                 arch_local_irq_restore(flags);          \
 186         } while (0)
 187 #define raw_local_save_flags(flags)                     \
 188         do {                                            \
 189                 typecheck(unsigned long, flags);        \
 190                 flags = arch_local_save_flags();        \
 191         } while (0)
 192 #define raw_irqs_disabled_flags(flags)                  \
 193         ({                                              \
 194                 typecheck(unsigned long, flags);        \
 195                 arch_irqs_disabled_flags(flags);        \
 196         })
 197 #define raw_irqs_disabled()             (arch_irqs_disabled())
 198 #define raw_safe_halt()                 arch_safe_halt()
 199
 200 /*
 201  * The local_irq_*() APIs are equal to the raw_local_irq*()
 202  * if !TRACE_IRQFLAGS.
 203  */
 204 #ifdef CONFIG_TRACE_IRQFLAGS
 205
 206 #define local_irq_enable()                              \
 207         do {                                            \
 208                 trace_hardirqs_on();                    \
 209                 raw_local_irq_enable();                 \
 210         } while (0)
 211
 212 #define local_irq_disable()                             \
 213         do {                                            \
 214                 bool was_disabled = raw_irqs_disabled();\
 215                 raw_local_irq_disable();                \
 216                 if (!was_disabled)                      \
 217                         trace_hardirqs_off();           \
 218         } while (0)
 219
 220 #define local_irq_save(flags)                           \
 221         do {                                            \
 222                 raw_local_irq_save(flags);              \
 223                 if (!raw_irqs_disabled_flags(flags))    \
 224                         trace_hardirqs_off();           \
 225         } while (0)
 226
 227 #define local_irq_restore(flags)                        \
 228         do {                                            \
 229                 if (!raw_irqs_disabled_flags(flags))    \
 230                         trace_hardirqs_on();            \
 231                 raw_local_irq_restore(flags);           \
 232         } while (0)
 233
 234 #define safe_halt()                             \
 235         do {                                    \
 236                 trace_hardirqs_on();            \
 237                 raw_safe_halt();                \
 238         } while (0)
 239
 240
 241 #else /* !CONFIG_TRACE_IRQFLAGS */
 242
 243 #define local_irq_enable()      do { raw_local_irq_enable(); } while (0)
 244 #define local_irq_disable()     do { raw_local_irq_disable(); } while (0)
 245 #define local_irq_save(flags)   do { raw_local_irq_save(flags); } while (0)
 246 #define local_irq_restore(flags) do { raw_local_irq_restore(flags); } while (0)
 247 #define safe_halt()             do { raw_safe_halt(); } while (0)
 248
 249 #endif /* CONFIG_TRACE_IRQFLAGS */
 250
 251 #define local_save_flags(flags) raw_local_save_flags(flags)
 252
 253 /*
 254  * Some architectures don't define arch_irqs_disabled(), so even if either
 255  * definition would be fine we need to use different ones for the time being
 256  * to avoid build issues.
 257  */
 258 #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
 259 #define irqs_disabled()                                 \
 260         ({                                              \
 261                 unsigned long _flags;                   \
 262                 raw_local_save_flags(_flags);           \
 263                 raw_irqs_disabled_flags(_flags);        \
 264         })
 265 #else /* !CONFIG_TRACE_IRQFLAGS_SUPPORT */
 266 #define irqs_disabled() raw_irqs_disabled()
 267 #endif /* CONFIG_TRACE_IRQFLAGS_SUPPORT */
 268
 269 #define irqs_disabled_flags(flags) raw_irqs_disabled_flags(flags)
 270
 271 DEFINE_LOCK_GUARD_0(irq, local_irq_disable(), local_irq_enable())
 272 DEFINE_LOCK_GUARD_0(irqsave,
 273                     local_irq_save(_T->flags),
 274                     local_irq_restore(_T->flags),
 275                     unsigned long flags)
 276
 277 #endif