[PATCH-v2] sched: Prevent wakeup to enter critical section needlessly

Check the waitqueue task list to be non empty before entering the critical section. This prevents locking the spin lock needlessly in case the queue was empty, and therefor also prevent scheduling overhead on a PREEMPT_RT system. Signed-off-by: Ivo Sieben --- v2: - We don't need the "careful"

[PATCH-v2] sched: Prevent wakeup to enter critical section needlessly

Check the waitqueue task list to be non empty before entering the critical section. This prevents locking the spin lock needlessly in case the queue was empty, and therefor also prevent scheduling overhead on a PREEMPT_RT system. Signed-off-by: Ivo Sieben meltedpiano...@gmail.com --- v2: - We