1 /* hardirq.h: 32-bit Sparc hard IRQ support.
3 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
4 * Copyright (C) 1998-2000 Anton Blanchard (anton@samba.org)
7 #ifndef __SPARC_HARDIRQ_H
8 #define __SPARC_HARDIRQ_H
10 #include <linux/config.h>
11 #include <linux/threads.h>
12 #include <linux/spinlock.h>
13 #include <linux/cache.h>
15 /* entry.S is sensitive to the offsets of these fields */ /* XXX P3 Is it? */
17 unsigned int __softirq_pending;
18 } ____cacheline_aligned irq_cpustat_t;
20 #include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
23 * We put the hardirq and softirq counter into the preemption
24 * counter. The bitmask has the following meaning:
26 * - bits 0-7 are the preemption count (max preemption depth: 256)
27 * - bits 8-15 are the softirq count (max # of softirqs: 256)
28 * - bits 16-23 are the hardirq count (max # of hardirqs: 256)
30 * - ( bit 26 is the PREEMPT_ACTIVE flag. )
32 * PREEMPT_MASK: 0x000000ff
33 * SOFTIRQ_MASK: 0x0000ff00
34 * HARDIRQ_MASK: 0x00ff0000
37 #define PREEMPT_BITS 8
38 #define SOFTIRQ_BITS 8
39 #define HARDIRQ_BITS 8
41 #define PREEMPT_SHIFT 0
42 #define SOFTIRQ_SHIFT (PREEMPT_SHIFT + PREEMPT_BITS)
43 #define HARDIRQ_SHIFT (SOFTIRQ_SHIFT + SOFTIRQ_BITS)
45 #define __MASK(x) ((1UL << (x))-1)
47 #define PREEMPT_MASK (__MASK(PREEMPT_BITS) << PREEMPT_SHIFT)
48 #define HARDIRQ_MASK (__MASK(HARDIRQ_BITS) << HARDIRQ_SHIFT)
49 #define SOFTIRQ_MASK (__MASK(SOFTIRQ_BITS) << SOFTIRQ_SHIFT)
51 #define hardirq_count() (preempt_count() & HARDIRQ_MASK)
52 #define softirq_count() (preempt_count() & SOFTIRQ_MASK)
53 #define irq_count() (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK))
55 #define PREEMPT_OFFSET (1UL << PREEMPT_SHIFT)
56 #define SOFTIRQ_OFFSET (1UL << SOFTIRQ_SHIFT)
57 #define HARDIRQ_OFFSET (1UL << HARDIRQ_SHIFT)
60 * The hardirq mask has to be large enough to have
61 * space for potentially all IRQ sources in the system
62 * nesting on a single CPU:
64 #if (1 << HARDIRQ_BITS) < NR_IRQS
65 # error HARDIRQ_BITS is too low!
69 * Are we doing bottom half or hardware interrupt processing?
70 * Are we in a softirq context? Interrupt context?
72 #define in_irq() (hardirq_count())
73 #define in_softirq() (softirq_count())
74 #define in_interrupt() (irq_count())
77 #define hardirq_trylock() (!in_interrupt())
78 #define hardirq_endlock() do { } while (0)
80 #define irq_enter() (preempt_count() += HARDIRQ_OFFSET)
83 #include <linux/smp_lock.h>
84 # define in_atomic() ((preempt_count() & ~PREEMPT_ACTIVE) != kernel_locked())
85 # define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1)
87 # define in_atomic() (preempt_count() != 0)
88 # define IRQ_EXIT_OFFSET HARDIRQ_OFFSET
92 preempt_count() -= IRQ_EXIT_OFFSET; \
93 if (!in_interrupt() && softirq_pending(smp_processor_id())) \
95 preempt_enable_no_resched(); \
99 # define synchronize_irq(irq) barrier()
101 extern void synchronize_irq(unsigned int irq);
104 #endif /* __SPARC_HARDIRQ_H */