Lock stealing and non cmpxchg will always go into the slow path.
This patch detects the fact that we didn't go through the work of
blocking and will exit early.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>