Messages in this thread | | | Date | Mon, 18 May 2020 22:12:35 -0700 | From | Andrew Morton <> | Subject | Re: [PATCH 10/10] mm/migrate.c: call detach_page_private to cleanup code |
| |
On Sun, 17 May 2020 23:47:18 +0200 Guoqing Jiang <guoqing.jiang@cloud.ionos.com> wrote:
> We can cleanup code a little by call detach_page_private here. > > ... > > --- a/mm/migrate.c > +++ b/mm/migrate.c > @@ -804,10 +804,7 @@ static int __buffer_migrate_page(struct address_space *mapping, > if (rc != MIGRATEPAGE_SUCCESS) > goto unlock_buffers; > > - ClearPagePrivate(page); > - set_page_private(newpage, page_private(page)); > - set_page_private(page, 0); > - put_page(page); > + set_page_private(newpage, detach_page_private(page)); > get_page(newpage); > > bh = head;
mm/migrate.c: In function '__buffer_migrate_page': ./include/linux/mm_types.h:243:52: warning: assignment makes integer from pointer without a cast [-Wint-conversion] #define set_page_private(page, v) ((page)->private = (v)) ^ mm/migrate.c:800:2: note: in expansion of macro 'set_page_private' set_page_private(newpage, detach_page_private(page)); ^~~~~~~~~~~~~~~~
The fact that set_page_private(detach_page_private()) generates a type mismatch warning seems deeply wrong, surely.
Please let's get the types sorted out - either unsigned long or void *, not half-one and half-the other. Whatever needs the least typecasting at callsites, I suggest.
And can we please implement set_page_private() and page_private() with inlined C code? There is no need for these to be macros.
| |