LXR linux/include/linux/hardirq.h

   1#ifndef LINUX_HARDIRQ_H
   2#define LINUX_HARDIRQ_H
   3
   4#include <linux/preempt.h>
   5#include <linux/lockdep.h>
   6#include <linux/ftrace_irq.h>
   7#include <linux/vtime.h>
   8#include <asm/hardirq.h>
   9
  10
  11extern void synchronize_irq(unsigned int irq);
  12extern bool synchronize_hardirq(unsigned int irq);
  13
  14#if defined(CONFIG_TINY_RCU)
  15
  16static inline void rcu_nmi_enter(void)
  17{
  18}
  19
  20static inline void rcu_nmi_exit(void)
  21{
  22}
  23
  24#else
  25extern void rcu_nmi_enter(void);
  26extern void rcu_nmi_exit(void);
  27#endif
  28
  29/*
  30 * It is safe to do non-atomic ops on ->hardirq_context,
  31 * because NMI handlers may not preempt and the ops are
  32 * always balanced, so the interrupted value of ->hardirq_context
  33 * will always be restored.
  34 */
  35#define __irq_enter()                                   \
  36        do {                                            \
  37                account_irq_enter_time(current);        \
  38                preempt_count_add(HARDIRQ_OFFSET);      \
  39                trace_hardirq_enter();                  \
  40        } while (0)
  41
  42/*
  43 * Enter irq context (on NO_HZ, update jiffies):
  44 */
  45extern void irq_enter(void);
  46
  47/*
  48 * Exit irq context without processing softirqs:
  49 */
  50#define __irq_exit()                                    \
  51        do {                                            \
  52                trace_hardirq_exit();                   \
  53                account_irq_exit_time(current);         \
  54                preempt_count_sub(HARDIRQ_OFFSET);      \
  55        } while (0)
  56
  57/*
  58 * Exit irq context and process softirqs if needed:
  59 */
  60extern void irq_exit(void);
  61
  62#define nmi_enter()                                             \
  63        do {                                                    \
  64                lockdep_off();                                  \
  65                ftrace_nmi_enter();                             \
  66                BUG_ON(in_nmi());                               \
  67                preempt_count_add(NMI_OFFSET + HARDIRQ_OFFSET); \
  68                rcu_nmi_enter();                                \
  69                trace_hardirq_enter();                          \
  70        } while (0)
  71
  72#define nmi_exit()                                              \
  73        do {                                                    \
  74                trace_hardirq_exit();                           \
  75                rcu_nmi_exit();                                 \
  76                BUG_ON(!in_nmi());                              \
  77                preempt_count_sub(NMI_OFFSET + HARDIRQ_OFFSET); \
  78                ftrace_nmi_exit();                              \
  79                lockdep_on();                                   \
  80        } while (0)
  81
  82#endif /* LINUX_HARDIRQ_H */
  83