Messages in this thread | | | Date | Tue, 19 May 2015 07:00:32 +0300 | From | "Kirill A. Shutemov" <> | Subject | Re: [PATCHv5 20/28] mm: differentiate page_mapped() from page_mapcount() for compound pages |
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On Mon, May 18, 2015 at 05:35:16PM +0200, Vlastimil Babka wrote: > On 04/23/2015 11:03 PM, Kirill A. Shutemov wrote: > >Let's define page_mapped() to be true for compound pages if any > >sub-pages of the compound page is mapped (with PMD or PTE). > > > >On other hand page_mapcount() return mapcount for this particular small > >page. > > > >This will make cases like page_get_anon_vma() behave correctly once we > >allow huge pages to be mapped with PTE. > > > >Most users outside core-mm should use page_mapcount() instead of > >page_mapped(). > > Does "should" mean that they do that now, or just that you would like them > to?
I would like them to.
> Should there be a warning before the function then?
Ok.
> >Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> > >Tested-by: Sasha Levin <sasha.levin@oracle.com> > > >--- a/include/linux/mm.h > >+++ b/include/linux/mm.h > >@@ -909,7 +909,16 @@ static inline pgoff_t page_file_index(struct page *page) > > (not shown in the diff) > > * Return true if this page is mapped into pagetables. > > */ > > Expand the comment? Especially if you put compound_head() there.
Ok.
> > static inline int page_mapped(struct page *page) > > Convert to proper bool while at it?
Ok.
-- Kirill A. Shutemov
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