File: /usr/src/linux/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 long __softirq_pending;
10     	unsigned int __local_irq_count;
11     	unsigned int __local_bh_count;
12     	unsigned int __syscall_count;
13     	struct task_struct * __ksoftirqd_task;
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 */
98