futex: Clean up stale comments

The futex key reference mechanism is long gone. Clean up the stale comments
which still mention it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211305.249178312@linutronix.de
This commit is contained in:
Thomas Gleixner 2021-08-15 23:29:06 +02:00 committed by Ingo Molnar
parent dc7109aaa2
commit c363b7ed79

View file

@ -1354,7 +1354,7 @@ static int lock_pi_update_atomic(u32 __user *uaddr, u32 uval, u32 newval)
* - 1 - acquired the lock;
* - <0 - error
*
* The hb->lock and futex_key refs shall be held by the caller.
* The hb->lock must be held by the caller.
*
* @exiting is only set when the return value is -EBUSY. If so, this holds
* a refcount on the exiting task on return and the caller needs to drop it
@ -2621,8 +2621,7 @@ static void futex_wait_queue_me(struct futex_hash_bucket *hb, struct futex_q *q,
*
* Setup the futex_q and locate the hash_bucket. Get the futex value and
* compare it with the expected value. Handle atomic faults internally.
* Return with the hb lock held and a q.key reference on success, and unlocked
* with no q.key reference on failure.
* Return with the hb lock held on success, and unlocked on failure.
*
* Return:
* - 0 - uaddr contains val and hb has been locked;
@ -2700,8 +2699,8 @@ static int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val,
current->timer_slack_ns);
retry:
/*
* Prepare to wait on uaddr. On success, holds hb lock and increments
* q.key refs.
* Prepare to wait on uaddr. On success, it holds hb->lock and q
* is initialized.
*/
ret = futex_wait_setup(uaddr, val, flags, &q, &hb);
if (ret)
@ -2712,7 +2711,6 @@ static int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val,
/* If we were woken (and unqueued), we succeeded, whatever. */
ret = 0;
/* unqueue_me() drops q.key ref */
if (!unqueue_me(&q))
goto out;
ret = -ETIMEDOUT;
@ -3205,8 +3203,8 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
q.requeue_pi_key = &key2;
/*
* Prepare to wait on uaddr. On success, increments q.key (key1) ref
* count.
* Prepare to wait on uaddr. On success, it holds hb->lock and q
* is initialized.
*/
ret = futex_wait_setup(uaddr, val, flags, &q, &hb);
if (ret)
@ -3235,9 +3233,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
* In order for us to be here, we know our q.key == key2, and since
* we took the hb->lock above, we also know that futex_requeue() has
* completed and we no longer have to concern ourselves with a wakeup
* race with the atomic proxy lock acquisition by the requeue code. The
* futex_requeue dropped our key1 reference and incremented our key2
* reference count.
* race with the atomic proxy lock acquisition by the requeue code.
*/
/*