Hi Badari,
This can be handled similarly to the way I suggested re: the kmem_cache
issue.  In fact, there already is this in place to deal with
the original name
change from mm_struct.rss to mm_struct._rss:

        MEMBER_OFFSET_INIT(mm_struct_rss,
"mm_struct", "rss");
        if (!VALID_MEMBER(mm_struct_rss))

MEMBER_OFFSET_INIT(mm_struct_rss, "mm_struct", "_rss");

i.e., itt needs yet another qualifier:

       MEMBER_OFFSET_INIT(mm_struct_rss,
"mm_struct", "rss");
       if (!VALID_MEMBER(mm_struct_rss))

MEMBER_OFFSET_INIT(mm_struct_rss, "mm_struct", "_rss");
       if (!VALID_MEMBER(mm_struct_rss))

MEMBER_OFFSET_INIT(mm_struct_rss, "mm_struct", "_file_rss");

Can you check that out?  I'm also (maybe incorrectly) presuming
that you were looking into fixing the kmem_cache issue as well?
Is that true?

Dave