David Rientjes <rientjes@xxxxxxxxxx> writes: > On Wed, 11 Mar 2020, Huang, Ying wrote: > >> diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h >> index 6f2fef7b0784..01144dd02a5f 100644 >> --- a/include/linux/mm_inline.h >> +++ b/include/linux/mm_inline.h >> @@ -9,10 +9,11 @@ >> * page_is_file_cache - should the page be on a file LRU or anon LRU? >> * @page: the page to test >> * >> - * Returns 1 if @page is page cache page backed by a regular filesystem, >> - * or 0 if @page is anonymous, tmpfs or otherwise ram or swap backed. >> - * Used by functions that manipulate the LRU lists, to sort a page >> - * onto the right LRU list. >> + * Returns 1 if @page is page cache page backed by a regular filesystem or >> + * anonymous page lazily freed (e.g. via MADV_FREE). Returns 0 if @page is >> + * normal anonymous page, tmpfs or otherwise ram or swap backed. Used by >> + * functions that manipulate the LRU lists, to sort a page onto the right LRU >> + * list. > > The function name is misleading: anonymous pages that can be lazily freed > are not file cache. This returns 1 because of the question it is asking: > anonymous lazily freeable pages should be on the file lru, not the anon > lru. So before adjusting the comment I'd suggest renaming the function to > something like page_is_file_lru(). Yes. I think page_is_file_lru() is a better name too. And whether tmpfs pages are file cache pages is confusing too. But I think we can do that after this patch if others think this is a good idea too. Best Regards, Huang, Ying
