include/asm-alpha/hardirq.h

   1 #ifndef _ALPHA_HARDIRQ_H
   2 #define _ALPHA_HARDIRQ_H
   3
   4 #include <linux/config.h>
   5 #include <linux/threads.h>
   6
   7 /* entry.S is sensitive to the offsets of these fields */
   8 typedef struct {
   9         unsigned int __softirq_active;
  10         unsigned int __softirq_mask;
  11         unsigned int __local_irq_count;
  12         unsigned int __local_bh_count;
  13         unsigned int __syscall_count;
  14 } ____cacheline_aligned irq_cpustat_t;
  15
  16 #include <linux/irq_cpustat.h>  /* Standard mappings for irq_cpustat_t above */
  17
  18 /*
  19  * Are we in an interrupt context? Either doing bottom half
  20  * or hardware interrupt processing?
  21  */
  22
  23 #define in_interrupt()                                          \
  24 ({                                                              \
  25         int __cpu = smp_processor_id();                         \
  26         (local_irq_count(__cpu) + local_bh_count(__cpu)) != 0;  \
  27 })
  28
  29 #define in_irq() (local_irq_count(smp_processor_id()) != 0)
  30
  31 #ifndef CONFIG_SMP
  32
  33 extern unsigned long __irq_attempt[];
  34 #define irq_attempt(cpu, irq)  ((void)(cpu), __irq_attempt[irq])
  35
  36 #define hardirq_trylock(cpu)    (local_irq_count(cpu) == 0)
  37 #define hardirq_endlock(cpu)    ((void) 0)
  38
  39 #define irq_enter(cpu, irq)     (local_irq_count(cpu)++)
  40 #define irq_exit(cpu, irq)      (local_irq_count(cpu)--)
  41
  42 #define synchronize_irq()       barrier()
  43
  44 #else
  45
  46 #define irq_attempt(cpu, irq) (cpu_data[cpu].irq_attempt[irq])
  47
  48 #include <asm/atomic.h>
  49 #include <linux/spinlock.h>
  50 #include <asm/smp.h>
  51
  52 extern int global_irq_holder;
  53 extern spinlock_t global_irq_lock;
  54
  55 static inline int irqs_running (void)
  56 {
  57         int i;
  58
  59         for (i = 0; i < smp_num_cpus; i++)
  60                 if (local_irq_count(i))
  61                         return 1;
  62         return 0;
  63 }
  64
  65 static inline void release_irqlock(int cpu)
  66 {
  67         /* if we didn't own the irq lock, just ignore.. */
  68         if (global_irq_holder == cpu) {
  69                 global_irq_holder = NO_PROC_ID;
  70                 spin_unlock(&global_irq_lock);
  71         }
  72 }
  73
  74 static inline void irq_enter(int cpu, int irq)
  75 {
  76         ++local_irq_count(cpu);
  77
  78         while (spin_is_locked(&global_irq_lock))
  79                 barrier();
  80 }
  81
  82 static inline void irq_exit(int cpu, int irq)
  83 {
  84         --local_irq_count(cpu);
  85 }
  86
  87 static inline int hardirq_trylock(int cpu)
  88 {
  89         return !local_irq_count(cpu) && !spin_is_locked(&global_irq_lock);
  90 }
  91
  92 #define hardirq_endlock(cpu)    do { } while (0)
  93
  94 extern void synchronize_irq(void);
  95
  96 #endif /* CONFIG_SMP */
  97 #endif /* _ALPHA_HARDIRQ_H */