Does an Object's TCriticalSection block calls from multiple threads to multiple locked methods?-CodePudding

I'm trying to track down an issue that I believe exists with an object's global TCriticalSection. Example code:

TMyObject = class
private
 FCS: TCriticalSection;
 FInternalObject: TSomeInternalObject;
public
 constructor Create;
 destructor Destroy; override;
 procedure WorkWithObjectA(Data: TDataTypeA);
 procedure WorkWithObjectB(Data: TDataTypeB);
end;

constructor TMyObject.Create;
begin
 FCS := TCriticalSection.Create;
 FInternalObject := TSomeInternalObject.Create;
end;

destructor TMyObject.Destroy;
begin
 FInternalObject.Free;
 FCS.Free;
 inherited;
end;

procedure TMyObject.WorkWithObjectA(Data: TDataTypeA);
begin
 FCS.Enter;
 try
  FInternalObject.DoProcessA(Data);
 finally
  FCS.Leave;
end;

procedure TMyObject.WorkWithObjectB(Data: TDataTypeB);
begin
 FCS.Enter;
 try
  FInternalObject.DoProcessB(Data);
 finally
  FCS.Leave;
end;

Question: If multiple threads are calling both procedures, will the TCriticalSection block WorkWithObjectB() if WorkWithObjectA() is blocking? This is a simplified version of a much more complex situation. The two procedures use greatly different structures, and thus cannot be easily combined into one blocking method... thoughts?

CodePudding user response：

Yes, if multiple threads are calling both procedures, the TCriticalSection will block both WorkWithObjectB() and WorkWithObjectA().

Note that in a complex situation, where WorkWithObjectB() will call WorkWithObjectA(), then there will be no deadlock. The lock occurs only when the call is in the context of a thread not already owning the lock.