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				/* hardirq.h: 32-bit Sparc hard IRQ support.				 *				 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)				 * Copyright (C) 1998-2000 Anton Blanchard (anton@samba.org)				 */								#ifndef __SPARC_HARDIRQ_H				#define __SPARC_HARDIRQ_H								#include 				#include 				#include 				#include 								/* entry.S is sensitive to the offsets of these fields */				typedef struct {					unsigned int __softirq_pending;					unsigned int __unused_1;				#ifndef CONFIG_SMP					unsigned int __local_irq_count;				#else					unsigned int __unused_on_SMP;	/* DaveM says use brlock for SMP irq. KAO */				#endif					unsigned int __local_bh_count;					unsigned int __syscall_count;				        struct task_struct * __ksoftirqd_task;				} ____cacheline_aligned irq_cpustat_t;								#include 	/* Standard mappings for irq_cpustat_t above */				/* Note that local_irq_count() is replaced by sparc64 specific version for SMP */								#ifndef CONFIG_SMP				#define irq_enter(cpu, irq)	((void)(irq), local_irq_count(cpu)++)				#define irq_exit(cpu, irq)	((void)(irq), local_irq_count(cpu)--)				#else				#undef local_irq_count				#define local_irq_count(cpu)	(__brlock_array[cpu][BR_GLOBALIRQ_LOCK])				#define irq_enter(cpu, irq)	br_read_lock(BR_GLOBALIRQ_LOCK)				#define irq_exit(cpu, irq)	br_read_unlock(BR_GLOBALIRQ_LOCK)				#endif								/*				 * Are we in an interrupt context? Either doing bottom half				 * or hardware interrupt processing?				 */				#define in_interrupt() ((local_irq_count(smp_processor_id()) + \						         local_bh_count(smp_processor_id())) != 0)								/* This tests only the local processors hw IRQ context disposition.  */				#define in_irq() (local_irq_count(smp_processor_id()) != 0)								#ifndef CONFIG_SMP								#define hardirq_trylock(cpu)	((void)(cpu), local_irq_count(smp_processor_id()) == 0)				#define hardirq_endlock(cpu)	do { (void)(cpu); } while(0)								#define synchronize_irq()	barrier()								#else /* (CONFIG_SMP) */								static __inline__ int irqs_running(void)				{					int i;									for (i = 0; i < smp_num_cpus; i++)						if (local_irq_count(cpu_logical_map(i)))							return 1;					return 0;				}								extern unsigned char global_irq_holder;								static inline void release_irqlock(int cpu)				{					/* if we didn't own the irq lock, just ignore... */					if(global_irq_holder == (unsigned char) cpu) {						global_irq_holder = NO_PROC_ID;						br_write_unlock(BR_GLOBALIRQ_LOCK);					}				}								static inline int hardirq_trylock(int cpu)				{					spinlock_t *lock = &__br_write_locks[BR_GLOBALIRQ_LOCK].lock;									return (!local_irq_count(cpu) && !spin_is_locked(lock));				}								#define hardirq_endlock(cpu)	do { (void)(cpu); } while (0)								extern void synchronize_irq(void);								#endif /* CONFIG_SMP */								#endif /* __SPARC_HARDIRQ_H */