On Wed, 19 Aug 2009 10:38:06 +0100
David Howells [off-list ref] wrote:

Thomas Gleixner [off-list ref] wrote:

quoted

quoted

which implies to me that spin_is_locked() will always return false.  Is this
expected behavior.

That's wrong. spin_is_locked should always return true on UP.

Surely it's not that simple?  Maybe spin_is_lock() should be undefined on UP.

That would lead to a lot of

#ifdef CONFIG_SMP

#endif

in drivers because there is driver code that uses spin_is_locked() in
fairly sensible fashion when dealing with locking.