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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 cpu_bh_disable(cpu) do { local_bh_count[(cpu)]++; barrier(); } while (0)
#define cpu_bh_enable(cpu) do { barrier(); local_bh_count[(cpu)]--; } while (0)
#define cpu_bh_trylock(cpu) (local_bh_count[(cpu)] ? 0 : (local_bh_count[(cpu)] = 1))
#define cpu_bh_endlock(cpu) (local_bh_count[(cpu)] = 0)
#define local_bh_disable() cpu_bh_disable(smp_processor_id())
#define local_bh_enable() cpu_bh_enable(smp_processor_id())
#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;
atomic_set(&bh_mask_count[nr], 0);
bh_mask |= 1 << nr;
}
extern inline void remove_bh(int nr)
{
bh_mask &= ~(1 << nr);
mb();
bh_base[nr] = NULL;
}
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 (cpu_bh_trylock(cpu)) {
if (!test_and_set_bit(0,&global_bh_count)) {
if (atomic_read(&global_bh_lock) == 0)
return 1;
clear_bit(0,&global_bh_count);
}
cpu_bh_endlock(cpu);
}
return 0;
}
static inline void softirq_endlock(int cpu)
{
cpu_bh_enable(cpu);
clear_bit(0,&global_bh_count);
}
#else
extern inline void start_bh_atomic(void)
{
local_bh_disable();
barrier();
}
extern inline void end_bh_atomic(void)
{
barrier();
local_bh_enable();
}
/* These are for the irq's testing the lock */
#define softirq_trylock(cpu) (cpu_bh_trylock(cpu))
#define softirq_endlock(cpu) (cpu_bh_endlock(cpu))
#define synchronize_bh() barrier()
#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);
atomic_inc(&bh_mask_count[nr]);
synchronize_bh();
}
extern inline void enable_bh(int nr)
{
if (atomic_dec_and_test(&bh_mask_count[nr]))
bh_mask |= 1 << nr;
}
#endif /* __ASM_SOFTIRQ_H */
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