/*
Put pins back to a pinbox. Usually called via lf_alloc_put_pins() or
lf_hash_put_pins().
DESCRIPTION
empty the purgatory (XXX deadlock warning below!),
push LF_PINS structure to a stack
*/
void _lf_pinbox_put_pins(LF_PINS *pins)
{
LF_PINBOX *pinbox= pins->pinbox;
uint32 top_ver, nr;
nr= pins->link;
#ifndef DBUG_OFF
{
/* This thread should not hold any pin. */
int i;
for (i= 0; i < LF_PINBOX_PINS; i++)
DBUG_ASSERT(pins->pin[i] == 0);
}
#endif /* DBUG_OFF */
/*
XXX this will deadlock if other threads will wait for
the caller to do something after _lf_pinbox_put_pins(),
and they would have pinned addresses that the caller wants to free.
Thus: only free pins when all work is done and nobody can wait for you!!!
*/
while (pins->purgatory_count)
{
_lf_pinbox_real_free(pins);
if (pins->purgatory_count)
{
my_atomic_rwlock_wrunlock(&pins->pinbox->pinarray.lock);
pthread_yield();
my_atomic_rwlock_wrlock(&pins->pinbox->pinarray.lock);
}
}
top_ver= pinbox->pinstack_top_ver;
do
{
pins->link= top_ver % LF_PINBOX_MAX_PINS;
} while (!my_atomic_cas32((int32 volatile*) &pinbox->pinstack_top_ver,
(int32*) &top_ver,
top_ver-pins->link+nr+LF_PINBOX_MAX_PINS));
return;
}
/*
Free an object allocated via pinbox allocator
DESCRIPTION
add an object to purgatory. if necessary, call _lf_pinbox_real_free()
to actually free something.
*/
void _lf_pinbox_free(LF_PINS *pins, void *addr)
{
add_to_purgatory(pins, addr);
if (pins->purgatory_count % LF_PURGATORY_SIZE)
_lf_pinbox_real_free(pins);
}