xref: /openbmc/linux/arch/parisc/include/asm/hardirq.h (revision 8569c914)
1 /* hardirq.h: PA-RISC hard IRQ support.
2  *
3  * Copyright (C) 2001 Matthew Wilcox <matthew@wil.cx>
4  *
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.
13  */
14 
15 #ifndef _PARISC_HARDIRQ_H
16 #define _PARISC_HARDIRQ_H
17 
18 #include <linux/threads.h>
19 #include <linux/irq.h>
20 
21 typedef struct {
22 	unsigned long __softirq_pending; /* set_bit is used on this */
23 } ____cacheline_aligned irq_cpustat_t;
24 
25 #include <linux/irq_cpustat.h>	/* Standard mappings for irq_cpustat_t above */
26 
27 void ack_bad_irq(unsigned int irq);
28 
29 #endif /* _PARISC_HARDIRQ_H */
30