1/* hardirq.h: 32-bit Sparc hard IRQ support. 2 * 3 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu) 4 * Copyright (C) 1998-2000 Anton Blanchard (anton@samba.org) 5 */ 6 7#ifndef __SPARC_HARDIRQ_H 8#define __SPARC_HARDIRQ_H 9 10#include <linux/config.h> 11#include <linux/threads.h> 12#include <linux/brlock.h> 13#include <linux/spinlock.h> 14 15/* entry.S is sensitive to the offsets of these fields */ 16typedef struct { 17 unsigned int __softirq_pending; 18 unsigned int __unused_1; 19#ifndef CONFIG_SMP 20 unsigned int __local_irq_count; 21#else 22 unsigned int __unused_on_SMP; /* DaveM says use brlock for SMP irq. KAO */ 23#endif 24 unsigned int __local_bh_count; 25 unsigned int __syscall_count; 26 struct task_struct * __ksoftirqd_task; 27} ____cacheline_aligned irq_cpustat_t; 28 29#include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */ 30/* Note that local_irq_count() is replaced by sparc64 specific version for SMP */ 31 32#ifndef CONFIG_SMP 33#define irq_enter(cpu, irq) ((void)(irq), local_irq_count(cpu)++) 34#define irq_exit(cpu, irq) ((void)(irq), local_irq_count(cpu)--) 35#else 36#undef local_irq_count 37#define local_irq_count(cpu) (__brlock_array[cpu][BR_GLOBALIRQ_LOCK]) 38#define irq_enter(cpu, irq) br_read_lock(BR_GLOBALIRQ_LOCK) 39#define irq_exit(cpu, irq) br_read_unlock(BR_GLOBALIRQ_LOCK) 40#endif 41 42/* 43 * Are we in an interrupt context? Either doing bottom half 44 * or hardware interrupt processing? 45 */ 46#define in_interrupt() ((local_irq_count(smp_processor_id()) + \ 47 local_bh_count(smp_processor_id())) != 0) 48 49/* This tests only the local processors hw IRQ context disposition. */ 50#define in_irq() (local_irq_count(smp_processor_id()) != 0) 51 52#ifndef CONFIG_SMP 53 54#define hardirq_trylock(cpu) ((void)(cpu), local_irq_count(smp_processor_id()) == 0) 55#define hardirq_endlock(cpu) do { (void)(cpu); } while(0) 56 57#define synchronize_irq() barrier() 58 59#else /* (CONFIG_SMP) */ 60 61static __inline__ int irqs_running(void) 62{ 63 int i; 64 65 for (i = 0; i < smp_num_cpus; i++) 66 if (local_irq_count(cpu_logical_map(i))) 67 return 1; 68 return 0; 69} 70 71extern unsigned char global_irq_holder; 72 73static inline void release_irqlock(int cpu) 74{ 75 /* if we didn't own the irq lock, just ignore... */ 76 if(global_irq_holder == (unsigned char) cpu) { 77 global_irq_holder = NO_PROC_ID; 78 br_write_unlock(BR_GLOBALIRQ_LOCK); 79 } 80} 81 82static inline int hardirq_trylock(int cpu) 83{ 84 spinlock_t *lock = &__br_write_locks[BR_GLOBALIRQ_LOCK].lock; 85 86 return (!local_irq_count(cpu) && !spin_is_locked(lock)); 87} 88 89#define hardirq_endlock(cpu) do { (void)(cpu); } while (0) 90 91extern void synchronize_irq(void); 92 93#endif /* CONFIG_SMP */ 94 95#endif /* __SPARC_HARDIRQ_H */ 96