Frédéric LATOUR wrote
We are using the credentials defined at the data source level to pull out data from SharePoint. Therefore, if you configure your data source with Windows Authentication, ERSDE will use the credentials of the user running the report for retrieving SharePoint data.

You don’t have to anything special when designing the report.
Hope this clarifies.
Thank you very much and I think I am getting better idea. Let me describe what I understand for now and correct me anything you find:
With Kerberos, SharePoint user credential can be used to trim the report data returned from a Sharepoint list.
Without Kerberor, trusted account is required and this account has to be defined in the data source file in a report library. Since this account may have different user permission (or no permission to any SharePoint list if it's for database connection only), to the one who is running the report, the returned results are not trimmed with the permission who is running the report.
Is this correct? Or in both case, returned results are the same?
Thank you very much.