include/asm-ia64/hardirq.h

   1 #ifndef _ASM_IA64_HARDIRQ_H
   2 #define _ASM_IA64_HARDIRQ_H
   3
   4 /*
   5  * Copyright (C) 1998-2000 Hewlett-Packard Co
   6  * Copyright (C) 1998-2000 David Mosberger-Tang <davidm@hpl.hp.com>
   7  */
   8
   9 #include <linux/config.h>
  10
  11 #include <linux/threads.h>
  12 #include <linux/irq.h>
  13
  14 /* entry.S is sensitive to the offsets of these fields */
  15 typedef struct {
  16         unsigned int __softirq_active;
  17         unsigned int __softirq_mask;
  18         unsigned int __local_irq_count;
  19         unsigned int __local_bh_count;
  20         unsigned int __syscall_count;
  21         unsigned int __nmi_count;       /* arch dependent */
  22 } ____cacheline_aligned irq_cpustat_t;
  23
  24 #include <linux/irq_cpustat.h>  /* Standard mappings for irq_cpustat_t above */
  25
  26 /*
  27  * Are we in an interrupt context? Either doing bottom half
  28  * or hardware interrupt processing?
  29  */
  30 #define in_interrupt()                                          \
  31 ({                                                              \
  32         int __cpu = smp_processor_id();                         \
  33         (local_irq_count(__cpu) + local_bh_count(__cpu)) != 0;  \
  34 })
  35
  36 #define in_irq() (local_irq_count(smp_processor_id()) != 0)
  37
  38 #ifndef CONFIG_SMP
  39 # define hardirq_trylock(cpu)           (local_irq_count(cpu) == 0)
  40 # define hardirq_endlock(cpu)           do { } while (0)
  41
  42 # define irq_enter(cpu, irq)            (local_irq_count(cpu)++)
  43 # define irq_exit(cpu, irq)             (local_irq_count(cpu)--)
  44
  45 # define synchronize_irq()              barrier()
  46 #else
  47
  48 #include <asm/atomic.h>
  49 #include <asm/smp.h>
  50
  51 extern unsigned int global_irq_holder;
  52 extern volatile unsigned long global_irq_lock;
  53
  54 static inline int irqs_running (void)
  55 {
  56         int i;
  57
  58         for (i = 0; i < smp_num_cpus; i++)
  59                 if (local_irq_count(i))
  60                         return 1;
  61         return 0;
  62 }
  63
  64 static inline void release_irqlock(int cpu)
  65 {
  66         /* if we didn't own the irq lock, just ignore.. */
  67         if (global_irq_holder == cpu) {
  68                 global_irq_holder = NO_PROC_ID;
  69                 clear_bit(0,&global_irq_lock);
  70         }
  71 }
  72
  73 static inline void irq_enter(int cpu, int irq)
  74 {
  75         local_irq_count(cpu)++;
  76
  77         while (test_bit(0,&global_irq_lock)) {
  78                 /* nothing */;
  79         }
  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) && !test_bit(0,&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 /* _ASM_IA64_HARDIRQ_H */