mm: add Set,ClearPageSwapCache stubs (6d91add0) · Commits · 戴 / test

If we add NOOP stubs for SetPageSwapCache() and ClearPageSwapCache(), then we can remove the #ifdef CONFIG_SWAPs from mm/migrate.c. Signed-off-by:

Christoph Lameter <cl@linux-foundation.org> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by:

include/linux/page-flags.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -228,6 +228,7 @@ PAGEFLAG_FALSE(HighMem)
		PAGEFLAG(SwapCache, swapcache)
		#else
		PAGEFLAG_FALSE(SwapCache)
		SETPAGEFLAG_NOOP(SwapCache) CLEARPAGEFLAG_NOOP(SwapCache)
		#endif

		#ifdef CONFIG_UNEVICTABLE_LRU

+0 −4

Original line number	Diff line number	Diff line
		@@ -300,12 +300,10 @@ static int migrate_page_move_mapping(struct address_space *mapping,
		* Now we know that no one else is looking at the page.
		*/
		get_page(newpage); /* add cache reference */
		#ifdef CONFIG_SWAP
		if (PageSwapCache(page)) {
		SetPageSwapCache(newpage);
		set_page_private(newpage, page_private(page));
		}
		#endif

		radix_tree_replace_slot(pslot, newpage);

		@@ -373,9 +371,7 @@ static void migrate_page_copy(struct page newpage, struct page page)

		mlock_migrate_page(newpage, page);

		#ifdef CONFIG_SWAP
		ClearPageSwapCache(page);
		#endif
		ClearPagePrivate(page);
		set_page_private(page, 0);
		/* page->mapping contains a flag for PageAnon() */