1 /* hardirq.h: 64-bit Sparc hard IRQ support.
3 * Copyright (C) 1997, 1998 David S. Miller (davem@caip.rutgers.edu)
6 #ifndef __SPARC64_HARDIRQ_H
7 #define __SPARC64_HARDIRQ_H
9 #include <linux/config.h>
10 #include <linux/threads.h>
11 #include <linux/spinlock.h>
12 #include <linux/cache.h>
14 /* rtrap.S is sensitive to the offsets of these fields */
16 unsigned int __softirq_pending;
17 } ____cacheline_aligned irq_cpustat_t;
19 #include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
22 * We put the hardirq and softirq counter into the preemption
23 * counter. The bitmask has the following meaning:
25 * - bits 0-7 are the preemption count (max preemption depth: 256)
26 * - bits 8-15 are the softirq count (max # of softirqs: 256)
27 * - bits 16-23 are the hardirq count (max # of hardirqs: 256)
29 * - ( bit 26 is the PREEMPT_ACTIVE flag. )
31 * PREEMPT_MASK: 0x000000ff
32 * SOFTIRQ_MASK: 0x0000ff00
33 * HARDIRQ_MASK: 0x00ff0000
36 #define PREEMPT_BITS 8
37 #define SOFTIRQ_BITS 8
38 #define HARDIRQ_BITS 8
40 #define PREEMPT_SHIFT 0
41 #define SOFTIRQ_SHIFT (PREEMPT_SHIFT + PREEMPT_BITS)
42 #define HARDIRQ_SHIFT (SOFTIRQ_SHIFT + SOFTIRQ_BITS)
44 #define __MASK(x) ((1UL << (x))-1)
46 #define PREEMPT_MASK (__MASK(PREEMPT_BITS) << PREEMPT_SHIFT)
47 #define HARDIRQ_MASK (__MASK(HARDIRQ_BITS) << HARDIRQ_SHIFT)
48 #define SOFTIRQ_MASK (__MASK(SOFTIRQ_BITS) << SOFTIRQ_SHIFT)
50 #define hardirq_count() (preempt_count() & HARDIRQ_MASK)
51 #define softirq_count() (preempt_count() & SOFTIRQ_MASK)
52 #define irq_count() (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK))
54 #define PREEMPT_OFFSET (1UL << PREEMPT_SHIFT)
55 #define SOFTIRQ_OFFSET (1UL << SOFTIRQ_SHIFT)
56 #define HARDIRQ_OFFSET (1UL << HARDIRQ_SHIFT)
59 * The hardirq mask has to be large enough to have
60 * space for potentially all IRQ sources in the system
61 * nesting on a single CPU:
63 #if (1 << HARDIRQ_BITS) < NR_IRQS
64 # error HARDIRQ_BITS is too low!
68 * Are we doing bottom half or hardware interrupt processing?
69 * Are we in a softirq context? Interrupt context?
71 #define in_irq() (hardirq_count())
72 #define in_softirq() (softirq_count())
73 #define in_interrupt() (irq_count())
76 #define hardirq_trylock() (!in_interrupt())
77 #define hardirq_endlock() do { } while (0)
79 #define irq_enter() (preempt_count() += HARDIRQ_OFFSET)
82 # include <linux/smp_lock.h>
83 # define in_atomic() ((preempt_count() & ~PREEMPT_ACTIVE) != kernel_locked())
84 # define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1)
86 # define in_atomic() (preempt_count() != 0)
87 # define IRQ_EXIT_OFFSET HARDIRQ_OFFSET
91 preempt_count() -= IRQ_EXIT_OFFSET; \
92 if (!in_interrupt() && softirq_pending(smp_processor_id())) \
94 preempt_enable_no_resched(); \
98 # define synchronize_irq(irq) barrier()
100 extern void synchronize_irq(unsigned int irq);
101 #endif /* CONFIG_SMP */
103 #endif /* !(__SPARC64_HARDIRQ_H) */