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#ifndef __ASM_SOFTIRQ_H
#define __ASM_SOFTIRQ_H
#include <asm/atomic.h>
#include <asm/hardirq.h>
extern unsigned int local_bh_count[NR_CPUS];
#define get_active_bhs() (bh_mask & bh_active)
#define clear_active_bhs(x) atomic_clear_mask((x),&bh_active)
extern inline void init_bh(int nr, void (*routine)(void))
{
bh_base[nr] = routine;
bh_mask_count[nr] = 0;
bh_mask |= 1 << nr;
}
extern inline void remove_bh(int nr)
{
bh_base[nr] = NULL;
bh_mask &= ~(1 << nr);
}
extern inline void mark_bh(int nr)
{
set_bit(nr, &bh_active);
}
#ifdef __SMP__
/*
* The locking mechanism for base handlers, to prevent re-entrancy,
* is entirely private to an implementation, it should not be
* referenced at all outside of this file.
*/
extern atomic_t global_bh_lock;
extern atomic_t global_bh_count;
extern void synchronize_bh(void);
static inline void start_bh_atomic(void)
{
atomic_inc(&global_bh_lock);
synchronize_bh();
}
static inline void end_bh_atomic(void)
{
atomic_dec(&global_bh_lock);
}
/* These are for the IRQs testing the lock */
static inline int softirq_trylock(int cpu)
{
if (!test_and_set_bit(0,&global_bh_count)) {
if (atomic_read(&global_bh_lock) == 0) {
++local_bh_count[cpu];
return 1;
}
clear_bit(0,&global_bh_count);
}
return 0;
}
static inline void softirq_endlock(int cpu)
{
local_bh_count[cpu]--;
clear_bit(0,&global_bh_count);
}
#else
extern inline void start_bh_atomic(void)
{
local_bh_count[smp_processor_id()]++;
barrier();
}
extern inline void end_bh_atomic(void)
{
barrier();
local_bh_count[smp_processor_id()]--;
}
/* These are for the irq's testing the lock */
#define softirq_trylock(cpu) (local_bh_count[cpu] ? 0 : (local_bh_count[cpu]=1))
#define softirq_endlock(cpu) (local_bh_count[cpu] = 0)
#define synchronize_bh() do { } while (0)
#endif /* SMP */
/*
* These use a mask count to correctly handle
* nested disable/enable calls
*/
extern inline void disable_bh(int nr)
{
bh_mask &= ~(1 << nr);
bh_mask_count[nr]++;
synchronize_bh();
}
extern inline void enable_bh(int nr)
{
if (!--bh_mask_count[nr])
bh_mask |= 1 << nr;
}
#endif /* __ASM_SOFTIRQ_H */
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