Include/asm-i386/hardirq.h
10721 #ifndef __ASM_HARDIRQ_H 10722 #define __ASM_HARDIRQ_H 10723 10724 #include <linux/tasks.h> 10725 10726 extern unsigned int local_irq_count[NR_CPUS]; 10727 10728 /* Are we in an interrupt context? Either doing bottom 10729 * half or hardware interrupt processing? */ 10730 #define in_interrupt() \ 10731 ({ int __cpu = smp_processor_id(); \ 10732 (local_irq_count[__cpu] + local_bh_count[__cpu] != 0); }) 10733 10734 #ifndef __SMP__ 10735 10736 #define hardirq_trylock(cpu) (local_irq_count[cpu] == 0) 10737 #define hardirq_endlock(cpu) do { } while (0) 10738 10739 #define hardirq_enter(cpu) (local_irq_count[cpu]++) 10740 #define hardirq_exit(cpu) (local_irq_count[cpu]--) 10741 10742 #define synchronize_irq() barrier() 10743 10744 #else 10745 10746 #include <asm/atomic.h> 10747 10748 extern unsigned char global_irq_holder; 10749 extern unsigned volatile int global_irq_lock; 10750 extern atomic_t global_irq_count; 10751 10752 static inline void release_irqlock(int cpu) 10753 { 10754 /* if we didn't own the irq lock, just ignore.. */ 10755 if (global_irq_holder == (unsigned char) cpu) { 10756 global_irq_holder = NO_PROC_ID; 10757 clear_bit(0,&global_irq_lock); 10758 } 10759 } 10760 10761 static inline void hardirq_enter(int cpu) 10762 { 10763 ++local_irq_count[cpu]; 10764 atomic_inc(&global_irq_count); 10765 } 10766 10767 static inline void hardirq_exit(int cpu) 10768 { 10769 atomic_dec(&global_irq_count); 10770 --local_irq_count[cpu]; 10771 } 10772 10773 static inline int hardirq_trylock(int cpu) 10774 { 10775 return !atomic_read(&global_irq_count) && 10776 !test_bit(0,&global_irq_lock); 10777 } 10778 10779 #define hardirq_endlock(cpu) do { } while (0) 10780 10781 extern void synchronize_irq(void); 10782 10783 #endif /* __SMP__ */ 10784 10785 #endif /* __ASM_HARDIRQ_H */
