Hi Chao,
I noticed this while reviewing [1]. _bt_gettrueroot() performs the same metapage checks as _bt_getmeta(), so using _bt_getmeta() here removes the duplicated code.
It looks good to me. These two code snippets are exactly identical,
so removing the redundant code is reasonable.
As can be seen from the contextual comments, this is not a performance-critical path either,
so we don’t need to worry about the performance overhead caused by function calls.
I also checked the changes made in commit dd299df, which essentially does the same thing for the function _bt_getrootheight.