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)  (__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 
irqs_running(void)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 
release_irqlock(int cpu)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 
irq_enter(int cpu,int irq)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 
irq_exit(int cpu,int irq)82 static inline void irq_exit(int cpu, int irq)
83 {
84         --local_irq_count(cpu);
85 }
86 
hardirq_trylock(int cpu)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