futex: distangle futex_requeue()

futex_requeue() is getting a bit long-winded, and will be getting more
so after the requeue_pi patch. Factor out the actual requeueing into a
nicely contained inline function to reduce function length and improve
legibility.

Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Darren Hart 2009-04-03 13:40:31 -07:00 committed by Thomas Gleixner
parent a72188d8a6
commit 9121e4783c

View File

@ -940,6 +940,34 @@ futex_wake_op(u32 __user *uaddr1, int fshared, u32 __user *uaddr2,
return ret;
}
/**
* requeue_futex() - Requeue a futex_q from one hb to another
* @q: the futex_q to requeue
* @hb1: the source hash_bucket
* @hb2: the target hash_bucket
* @key2: the new key for the requeued futex_q
*/
static inline
void requeue_futex(struct futex_q *q, struct futex_hash_bucket *hb1,
struct futex_hash_bucket *hb2, union futex_key *key2)
{
/*
* If key1 and key2 hash to the same bucket, no need to
* requeue.
*/
if (likely(&hb1->chain != &hb2->chain)) {
plist_del(&q->list, &hb1->chain);
plist_add(&q->list, &hb2->chain);
q->lock_ptr = &hb2->lock;
#ifdef CONFIG_DEBUG_PI_LIST
q->list.plist.lock = &hb2->lock;
#endif
}
get_futex_key_refs(key2);
q->key = *key2;
}
/*
* Requeue all waiters hashed on one physical page to another
* physical page.
@ -999,20 +1027,7 @@ static int futex_requeue(u32 __user *uaddr1, int fshared, u32 __user *uaddr2,
if (++ret <= nr_wake) {
wake_futex(this);
} else {
/*
* If key1 and key2 hash to the same bucket, no need to
* requeue.
*/
if (likely(head1 != &hb2->chain)) {
plist_del(&this->list, &hb1->chain);
plist_add(&this->list, &hb2->chain);
this->lock_ptr = &hb2->lock;
#ifdef CONFIG_DEBUG_PI_LIST
this->list.plist.lock = &hb2->lock;
#endif
}
this->key = key2;
get_futex_key_refs(&key2);
requeue_futex(this, hb1, hb2, &key2);
drop_count++;
if (ret - nr_wake >= nr_requeue)