akpm@xxxxxxxxxxxxxxxxxxxx wrote: > There is a READ_ONCE() in the macro of compound_head(), which will prevent > compiler from optimizing the code when there are more than once calling of > it in a function. Remove the redundant calling of compound_head() from > page_to_index() and page_add_file_rmap() for better code generation. > > Link: https://lkml.kernel.org/r/20210811101431.83940-1-songmuchun@xxxxxxxxxxxxx > Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> > Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> > Cc: William Kucharski <william.kucharski@xxxxxxxxxx> > Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> > Cc: David Howells <dhowells@xxxxxxxxxx> > Cc: Johannes Weiner <hannes@xxxxxxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Seems reasonable, but will it conflict with Willy's folio patchset? Reviewed-by: David Howells <dhowells@xxxxxxxxxx>
