Commit 5ed59af8 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull core/locking changes for v3.4 from Ingo Molnar

* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  futex: Simplify return logic
  futex: Cover all PI opcodes with cmpxchg enabled check
parents b7f077d7 81b40539

kernel/futex.c

+23 −28
Original line number Diff line number Diff line
@@ -2628,7 +2628,7 @@ void exit_robust_list(struct task_struct *curr) 
long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,

		u32 __user *uaddr2, u32 val2, u32 val3)

{

	int ret = -ENOSYS, cmd = op & FUTEX_CMD_MASK;

	int cmd = op & FUTEX_CMD_MASK;

	unsigned int flags = 0;



	if (!(op & FUTEX_PRIVATE_FLAG))
@@ -2640,50 +2640,45 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, 
			return -ENOSYS;

	}



	switch (cmd) {

	case FUTEX_LOCK_PI:

	case FUTEX_UNLOCK_PI:

	case FUTEX_TRYLOCK_PI:

	case FUTEX_WAIT_REQUEUE_PI:

	case FUTEX_CMP_REQUEUE_PI:

		if (!futex_cmpxchg_enabled)

			return -ENOSYS;

	}



	switch (cmd) {

	case FUTEX_WAIT:

		val3 = FUTEX_BITSET_MATCH_ANY;

	case FUTEX_WAIT_BITSET:

		ret = futex_wait(uaddr, flags, val, timeout, val3);

		break;

		return futex_wait(uaddr, flags, val, timeout, val3);

	case FUTEX_WAKE:

		val3 = FUTEX_BITSET_MATCH_ANY;

	case FUTEX_WAKE_BITSET:

		ret = futex_wake(uaddr, flags, val, val3);

		break;

		return futex_wake(uaddr, flags, val, val3);

	case FUTEX_REQUEUE:

		ret = futex_requeue(uaddr, flags, uaddr2, val, val2, NULL, 0);

		break;

		return futex_requeue(uaddr, flags, uaddr2, val, val2, NULL, 0);

	case FUTEX_CMP_REQUEUE:

		ret = futex_requeue(uaddr, flags, uaddr2, val, val2, &val3, 0);

		break;

		return futex_requeue(uaddr, flags, uaddr2, val, val2, &val3, 0);

	case FUTEX_WAKE_OP:

		ret = futex_wake_op(uaddr, flags, uaddr2, val, val2, val3);

		break;

		return futex_wake_op(uaddr, flags, uaddr2, val, val2, val3);

	case FUTEX_LOCK_PI:

		if (futex_cmpxchg_enabled)

			ret = futex_lock_pi(uaddr, flags, val, timeout, 0);

		break;

		return futex_lock_pi(uaddr, flags, val, timeout, 0);

	case FUTEX_UNLOCK_PI:

		if (futex_cmpxchg_enabled)

			ret = futex_unlock_pi(uaddr, flags);

		break;

		return futex_unlock_pi(uaddr, flags);

	case FUTEX_TRYLOCK_PI:

		if (futex_cmpxchg_enabled)

			ret = futex_lock_pi(uaddr, flags, 0, timeout, 1);

		break;

		return futex_lock_pi(uaddr, flags, 0, timeout, 1);

	case FUTEX_WAIT_REQUEUE_PI:

		val3 = FUTEX_BITSET_MATCH_ANY;

		ret = futex_wait_requeue_pi(uaddr, flags, val, timeout, val3,

		return futex_wait_requeue_pi(uaddr, flags, val, timeout, val3,

					     uaddr2);

		break;

	case FUTEX_CMP_REQUEUE_PI:

		ret = futex_requeue(uaddr, flags, uaddr2, val, val2, &val3, 1);

		break;

	default:

		ret = -ENOSYS;

		return futex_requeue(uaddr, flags, uaddr2, val, val2, &val3, 1);

	}

	return ret;

	return -ENOSYS;

}