#! stap -p2
# Per bz3016, this should get through the semantic pass without warnings.
probe kernel.function("do_mpage_readpage") {
    printf("\n page->mapping %p",$page->mapping)
    %( kernel_v >= "2.6.22" %?
       printf("\n page->first_page->mapping %p",$page->first_page->mapping)
    %)

}