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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 | #ifndef LINUX_HARDIRQ_H
#define LINUX_HARDIRQ_H
#include <linux/preempt.h>
#include <linux/smp_lock.h>
#include <linux/lockdep.h>
#include <asm/hardirq.h>
#include <asm/system.h>
/*
* We put the hardirq and softirq counter into the preemption
* counter. The bitmask has the following meaning:
*
* - bits 0-7 are the preemption count (max preemption depth: 256)
* - bits 8-15 are the softirq count (max # of softirqs: 256)
*
* The hardirq count can be overridden per architecture, the default is:
*
* - bits 16-27 are the hardirq count (max # of hardirqs: 4096)
* - ( bit 28 is the PREEMPT_ACTIVE flag. )
*
* PREEMPT_MASK: 0x000000ff
* SOFTIRQ_MASK: 0x0000ff00
* HARDIRQ_MASK: 0x0fff0000
*/
#define PREEMPT_BITS 8
#define SOFTIRQ_BITS 8
#ifndef HARDIRQ_BITS
#define HARDIRQ_BITS 12
#ifndef MAX_HARDIRQS_PER_CPU
#define MAX_HARDIRQS_PER_CPU NR_IRQS
#endif
/*
* The hardirq mask has to be large enough to have space for potentially
* all IRQ sources in the system nesting on a single CPU.
*/
#if (1 << HARDIRQ_BITS) < MAX_HARDIRQS_PER_CPU
# error HARDIRQ_BITS is too low!
#endif
#endif
#define PREEMPT_SHIFT 0
#define SOFTIRQ_SHIFT (PREEMPT_SHIFT + PREEMPT_BITS)
#define HARDIRQ_SHIFT (SOFTIRQ_SHIFT + SOFTIRQ_BITS)
#define __IRQ_MASK(x) ((1UL << (x))-1)
#define PREEMPT_MASK (__IRQ_MASK(PREEMPT_BITS) << PREEMPT_SHIFT)
#define SOFTIRQ_MASK (__IRQ_MASK(SOFTIRQ_BITS) << SOFTIRQ_SHIFT)
#define HARDIRQ_MASK (__IRQ_MASK(HARDIRQ_BITS) << HARDIRQ_SHIFT)
#define PREEMPT_OFFSET (1UL << PREEMPT_SHIFT)
#define SOFTIRQ_OFFSET (1UL << SOFTIRQ_SHIFT)
#define HARDIRQ_OFFSET (1UL << HARDIRQ_SHIFT)
#if PREEMPT_ACTIVE < (1 << (HARDIRQ_SHIFT + HARDIRQ_BITS))
#error PREEMPT_ACTIVE is too low!
#endif
#define hardirq_count() (preempt_count() & HARDIRQ_MASK)
#define softirq_count() (preempt_count() & SOFTIRQ_MASK)
#define irq_count() (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK))
/*
* Are we doing bottom half or hardware interrupt processing?
* Are we in a softirq context? Interrupt context?
*/
#define in_irq() (hardirq_count())
#define in_softirq() (softirq_count())
#define in_interrupt() (irq_count())
#if defined(CONFIG_PREEMPT) && !defined(CONFIG_PREEMPT_BKL)
# define in_atomic() ((preempt_count() & ~PREEMPT_ACTIVE) != kernel_locked())
#else
# define in_atomic() ((preempt_count() & ~PREEMPT_ACTIVE) != 0)
#endif
#ifdef CONFIG_PREEMPT
# define preemptible() (preempt_count() == 0 && !irqs_disabled())
# define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1)
#else
# define preemptible() 0
# define IRQ_EXIT_OFFSET HARDIRQ_OFFSET
#endif
#ifdef CONFIG_SMP
extern void synchronize_irq(unsigned int irq);
#else
# define synchronize_irq(irq) barrier()
#endif
struct task_struct;
#ifndef CONFIG_VIRT_CPU_ACCOUNTING
static inline void account_system_vtime(struct task_struct *tsk)
{
}
#endif
/*
* It is safe to do non-atomic ops on ->hardirq_context,
* because NMI handlers may not preempt and the ops are
* always balanced, so the interrupted value of ->hardirq_context
* will always be restored.
*/
#define irq_enter() \
do { \
account_system_vtime(current); \
add_preempt_count(HARDIRQ_OFFSET); \
trace_hardirq_enter(); \
} while (0)
/*
* Exit irq context without processing softirqs:
*/
#define __irq_exit() \
do { \
trace_hardirq_exit(); \
account_system_vtime(current); \
sub_preempt_count(HARDIRQ_OFFSET); \
} while (0)
/*
* Exit irq context and process softirqs if needed:
*/
extern void irq_exit(void);
#define nmi_enter() do { lockdep_off(); irq_enter(); } while (0)
#define nmi_exit() do { __irq_exit(); lockdep_on(); } while (0)
#endif /* LINUX_HARDIRQ_H */
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