include/linux/hardirq.h

   1 #ifndef LINUX_HARDIRQ_H
   2 #define LINUX_HARDIRQ_H
   3
   4 #include <linux/preempt_mask.h>
   5 #include <linux/lockdep.h>
   6 #include <linux/ftrace_irq.h>
   7 #include <linux/vtime.h>
   8
   9
  10 extern void synchronize_irq(unsigned int irq);
  11
  12 #if defined(CONFIG_TINY_RCU)
  13
  14 static inline void rcu_nmi_enter(void)
  15 {
  16 }
  17
  18 static inline void rcu_nmi_exit(void)
  19 {
  20 }
  21
  22 #else
  23 extern void rcu_nmi_enter(void);
  24 extern void rcu_nmi_exit(void);
  25 #endif
  26
  27 /*
  28  * It is safe to do non-atomic ops on ->hardirq_context,
  29  * because NMI handlers may not preempt and the ops are
  30  * always balanced, so the interrupted value of ->hardirq_context
  31  * will always be restored.
  32  */
  33 #define __irq_enter()                                   \
  34         do {                                            \
  35                 account_irq_enter_time(current);        \
  36                 preempt_count_add(HARDIRQ_OFFSET);      \
  37                 trace_hardirq_enter();                  \
  38         } while (0)
  39
  40 /*
  41  * Enter irq context (on NO_HZ, update jiffies):
  42  */
  43 extern void irq_enter(void);
  44
  45 /*
  46  * Exit irq context without processing softirqs:
  47  */
  48 #define __irq_exit()                                    \
  49         do {                                            \
  50                 trace_hardirq_exit();                   \
  51                 account_irq_exit_time(current);         \
  52                 preempt_count_sub(HARDIRQ_OFFSET);      \
  53         } while (0)
  54
  55 /*
  56  * Exit irq context and process softirqs if needed:
  57  */
  58 extern void irq_exit(void);
  59
  60 #define nmi_enter()                                             \
  61         do {                                                    \
  62                 lockdep_off();                                  \
  63                 ftrace_nmi_enter();                             \
  64                 BUG_ON(in_nmi());                               \
  65                 preempt_count_add(NMI_OFFSET + HARDIRQ_OFFSET); \
  66                 rcu_nmi_enter();                                \
  67                 trace_hardirq_enter();                          \
  68         } while (0)
  69
  70 #define nmi_exit()                                              \
  71         do {                                                    \
  72                 trace_hardirq_exit();                           \
  73                 rcu_nmi_exit();                                 \
  74                 BUG_ON(!in_nmi());                              \
  75                 preempt_count_sub(NMI_OFFSET + HARDIRQ_OFFSET); \
  76                 ftrace_nmi_exit();                              \
  77                 lockdep_on();                                   \
  78         } while (0)
  79
  80 #endif /* LINUX_HARDIRQ_H */