1 /* hardirq.h: PA-RISC hard IRQ support.
3 * Copyright (C) 2001 Matthew Wilcox <matthew@wil.cx>
5 * The locking is really quite interesting. There's a cpu-local
6 * count of how many interrupts are being handled, and a global
7 * lock. An interrupt can only be serviced if the global lock
8 * is free. You can't be sure no more interrupts are being
9 * serviced until you've acquired the lock and then checked
10 * all the per-cpu interrupt counts are all zero. It's a specialised
11 * br_lock, and that's exactly how Sparc does it. We don't because
12 * it's more locking for us. This way is lock-free in the interrupt path.
15 #ifndef _PARISC_HARDIRQ_H
16 #define _PARISC_HARDIRQ_H
18 #include <linux/config.h>
19 #include <linux/threads.h>
20 #include <linux/cache.h>
21 #include <linux/irq.h>
24 unsigned long __softirq_pending; /* set_bit is used on this */
25 } ____cacheline_aligned irq_cpustat_t;
27 #include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
29 #define HARDIRQ_BITS 16
32 * The hardirq mask has to be large enough to have space for potentially all
33 * IRQ sources in the system nesting on a single CPU:
35 #if (1 << HARDIRQ_BITS) < NR_IRQS
36 # error HARDIRQ_BITS is too low!
39 void ack_bad_irq(unsigned int irq);
41 #endif /* _PARISC_HARDIRQ_H */