include/asm-mips64/hardirq.h

   1 /* $Id: hardirq.h,v 1.6 2000/03/07 15:45:42 ralf Exp $
   2  *
   3  * This file is subject to the terms and conditions of the GNU General Public
   4  * License.  See the file "COPYING" in the main directory of this archive
   5  * for more details.
   6  *
   7  * Copyright (C) 1997 - 2000 by Ralf Baechle
   8  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
   9  */
  10 #ifndef _ASM_HARDIRQ_H
  11 #define _ASM_HARDIRQ_H
  12
  13 #include <linux/config.h>
  14 #include <linux/threads.h>
  15 #include <linux/irq.h>
  16
  17 /* entry.S is sensitive to the offsets of these fields */
  18 typedef struct {
  19         unsigned int __softirq_active;
  20         unsigned int __softirq_mask;
  21         unsigned int __local_irq_count;
  22         unsigned int __local_bh_count;
  23         unsigned int __syscall_count;
  24 } ____cacheline_aligned irq_cpustat_t;
  25
  26 #include <linux/irq_cpustat.h>  /* Standard mappings for irq_cpustat_t above */
  27
  28 /*
  29  * Are we in an interrupt context? Either doing bottom half
  30  * or hardware interrupt processing?
  31  */
  32 #define in_interrupt() ({ int __cpu = smp_processor_id(); \
  33         (local_irq_count(__cpu) + local_bh_count(__cpu) != 0); })
  34 #define in_irq() (local_irq_count(smp_processor_id()) != 0)
  35
  36 #ifndef CONFIG_SMP
  37
  38 #define hardirq_trylock(cpu)    (local_irq_count(cpu) == 0)
  39 #define hardirq_endlock(cpu)    do { } while (0)
  40
  41 #define irq_enter(cpu, irq)     (local_irq_count(cpu)++)
  42 #define irq_exit(cpu, irq)      (local_irq_count(cpu)--)
  43
  44 #define synchronize_irq()       barrier();
  45
  46 #else
  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 int hardirq_trylock(int cpu)
  75 {
  76         return !local_irq_count(cpu) && !spin_is_locked(&global_irq_lock);
  77 }
  78
  79 #define hardirq_endlock(cpu)    do { } while (0)
  80
  81 static inline void irq_enter(int cpu, int irq)
  82 {
  83         ++local_irq_count(cpu);
  84
  85         while (spin_is_locked(&global_irq_lock))
  86                 barrier();
  87 }
  88
  89 static inline void irq_exit(int cpu, int irq)
  90 {
  91         --local_irq_count(cpu);
  92 }
  93
  94 extern void synchronize_irq(void);
  95
  96 #endif /* CONFIG_SMP */
  97
  98 #endif /* _ASM_HARDIRQ_H */