LXR linux/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#include <asm/hardirq.h>
   9
  10
  11#if defined(CONFIG_SMP) || defined(CONFIG_GENERIC_HARDIRQS)
  12extern void synchronize_irq(unsigned int irq);
  13extern void synchronize_hardirq(unsigned int irq);
  14#else
  15# define synchronize_irq(irq)   barrier()
  16# define synchronize_hardirq(irq)       barrier()
  17#endif
  18
  19#if defined(CONFIG_TINY_RCU) || defined(CONFIG_TINY_PREEMPT_RCU)
  20
  21static inline void rcu_nmi_enter(void)
  22{
  23}
  24
  25static inline void rcu_nmi_exit(void)
  26{
  27}
  28
  29#else
  30extern void rcu_nmi_enter(void);
  31extern void rcu_nmi_exit(void);
  32#endif
  33
  34/*
  35 * It is safe to do non-atomic ops on ->hardirq_context,
  36 * because NMI handlers may not preempt and the ops are
  37 * always balanced, so the interrupted value of ->hardirq_context
  38 * will always be restored.
  39 */
  40#define __irq_enter()                                   \
  41        do {                                            \
  42                account_irq_enter_time(current);        \
  43                add_preempt_count(HARDIRQ_OFFSET);      \
  44                trace_hardirq_enter();                  \
  45        } while (0)
  46
  47/*
  48 * Enter irq context (on NO_HZ, update jiffies):
  49 */
  50extern void irq_enter(void);
  51
  52/*
  53 * Exit irq context without processing softirqs:
  54 */
  55#define __irq_exit()                                    \
  56        do {                                            \
  57                trace_hardirq_exit();                   \
  58                account_irq_exit_time(current);         \
  59                sub_preempt_count(HARDIRQ_OFFSET);      \
  60        } while (0)
  61
  62/*
  63 * Exit irq context and process softirqs if needed:
  64 */
  65extern void irq_exit(void);
  66
  67#define nmi_enter()                                             \
  68        do {                                                    \
  69                lockdep_off();                                  \
  70                ftrace_nmi_enter();                             \
  71                BUG_ON(in_nmi());                               \
  72                add_preempt_count(NMI_OFFSET + HARDIRQ_OFFSET); \
  73                rcu_nmi_enter();                                \
  74                trace_hardirq_enter();                          \
  75        } while (0)
  76
  77#define nmi_exit()                                              \
  78        do {                                                    \
  79                trace_hardirq_exit();                           \
  80                rcu_nmi_exit();                                 \
  81                BUG_ON(!in_nmi());                              \
  82                sub_preempt_count(NMI_OFFSET + HARDIRQ_OFFSET); \
  83                ftrace_nmi_exit();                              \
  84                lockdep_on();                                   \
  85        } while (0)
  86
  87#endif /* LINUX_HARDIRQ_H */
  88