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#ifndef __ASM_HARDIRQ_H
#define __ASM_HARDIRQ_H
#include <linux/config.h>
#include <linux/threads.h>
#include <linux/irq.h>
/* assembly code in softirq.h is sensitive to the offsets of these fields */
typedef struct {
unsigned int __softirq_pending;
unsigned int __local_irq_count;
unsigned int __local_bh_count;
unsigned int __syscall_count;
struct task_struct * __ksoftirqd_task; /* waitqueue is too large */
unsigned int __nmi_count; /* arch dependent */
} ____cacheline_aligned irq_cpustat_t;
#include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */
/*
* Are we in an interrupt context? Either doing bottom half
* or hardware interrupt processing?
*/
#define in_interrupt() ({ int __cpu = smp_processor_id(); \
(local_irq_count(__cpu) + local_bh_count(__cpu) != 0); })
#define in_irq() (local_irq_count(smp_processor_id()) != 0)
#ifndef CONFIG_SMP
#define hardirq_trylock(cpu) (local_irq_count(cpu) == 0)
#define hardirq_endlock(cpu) do { } while (0)
#define irq_enter(cpu, irq) (local_irq_count(cpu)++)
#define irq_exit(cpu, irq) (local_irq_count(cpu)--)
#define synchronize_irq() barrier()
#else
#include <asm/atomic.h>
#include <asm/smp.h>
extern unsigned char global_irq_holder;
extern unsigned volatile long global_irq_lock; /* long for set_bit -RR */
static inline int irqs_running (void)
{
int i;
for (i = 0; i < smp_num_cpus; i++)
if (local_irq_count(i))
return 1;
return 0;
}
static inline void release_irqlock(int cpu)
{
/* if we didn't own the irq lock, just ignore.. */
if (global_irq_holder == (unsigned char) cpu) {
global_irq_holder = NO_PROC_ID;
clear_bit(0,&global_irq_lock);
}
}
static inline void irq_enter(int cpu, int irq)
{
++local_irq_count(cpu);
while (test_bit(0,&global_irq_lock)) {
/* nothing */;
}
}
static inline void irq_exit(int cpu, int irq)
{
--local_irq_count(cpu);
}
static inline int hardirq_trylock(int cpu)
{
return !local_irq_count(cpu) && !test_bit(0,&global_irq_lock);
}
#define hardirq_endlock(cpu) do { } while (0)
extern void synchronize_irq(void);
#endif /* CONFIG_SMP */
#endif /* __ASM_HARDIRQ_H */
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