[SPARK-32111] Cleanup locks and docs in CoarseGrainedSchedulerBackend

• Type: Improvement
• Status: Open
• Priority: Trivial
• Resolution: Unresolved
• Affects Version/s: 3.1.0, 4.0.0
• Component/s: Spark Core
• Target Version/s: 4.0.0
• Assignee: Unassigned
• Reporter: Holden Karau
• Created: 26/Jun/20 20:20
• Updated: 07/Aug/23 17:25

Description

Our locking is inconsistent inside of CoarseGrainedSchedulerBackend. In production this doesn't matter because the methods in are called from inside of ThreadSafeRPC but it would be better to cleanup the locks and docs to be consistent especially since other schedulers inherit from CoarseGrainedSchedulerBackend.