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#ifndef _ALPHA_SOFTIRQ_H
#define _ALPHA_SOFTIRQ_H
#include <linux/stddef.h>
#include <asm/atomic.h>
#include <asm/hardirq.h>
/*
* This works but is wrong - on SMP it should disable only on the
* current CPU and shouldn't synchronize like the heavy global
* disable does. Oh, well.
*
* See the x86 version for an example.
*/
#define local_bh_enable() start_bh_atomic()
#define local_bh_disable() end_bh_atomic()
extern unsigned int local_bh_count[NR_CPUS];
#define get_active_bhs() (bh_mask & bh_active)
static inline void clear_active_bhs(unsigned long x)
{
unsigned long temp;
__asm__ __volatile__(
"1: ldq_l %0,%1\n"
" bic %0,%2,%0\n"
" stq_c %0,%1\n"
" beq %0,2f\n"
".section .text2,\"ax\"\n"
"2: br 1b\n"
".previous"
:"=&r" (temp), "=m" (bh_active)
:"Ir" (x), "m" (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_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 irq's 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);
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 /* _ALPHA_SOFTIRQ_H */
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