Remove locking in CursorReadingTask.getState()#5203
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CursorReadingTask used a single lock to guard both the lifecycle state and access to the underlying MongoCursor. As the cursor read happens through a long-polling tryNext() call that can block for up to maxAwaitTime, any concurrent getState() invocation (e.g. via Subscription.isActive()) had to wait for the in-flight poll to complete before it could obtain the lock, contradicting the non-blocking nature of the operation. We now hold the state in a volatile field and read it without acquiring the lock so that getState() returns immediately regardless of an ongoing cursor read. Lifecycle transitions remain guarded by the lock to keep state changes and cursor handling consistent. Closes #5201
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CursorReadingTaskused a single lock to guard both the lifecycle state and access to the underlyingMongoCursor.As the cursor read happens through a long-polling
tryNext()call that can block for up to maxAwaitTime, any concurrent getState() invocation (e.g. viaSubscription.isActive()) had to wait for the in-flight poll to complete before it could obtain the lock, contradicting the non-blocking nature of the operation.We now hold the state in a volatile field and read it without acquiring the lock so that getState() returns immediately regardless of an ongoing cursor read. Lifecycle transitions remain guarded by the lock to keep state changes and cursor handling consistent.
Closes #5201