[RFC] [PATCH 3/5] Dynamically allocated pageflags - PageSwapCache conversion.

[Nigel Cunningham <nigel@nigel.suspend2.net>]

Switch PageSwapCache flag to use dynamically allocated pageflags.

Signed-off-by: Nigel Cunningham <nigel@nigel.suspend2.net>

 include/linux/page-flags.h |    7 ++++---
 mm/dyn_pageflags.c         |    3 +++
 2 files changed, 7 insertions(+), 3 deletions(-)
diff -ruNp 921-page-swap-cache-pageflag.patch-old/include/linux/page-flags.h 921-page-swap-cache-pageflag.patch-new/include/linux/page-flags.h
--- 921-page-swap-cache-pageflag.patch-old/include/linux/page-flags.h	2007-07-23 22:13:16.000000000 +1000
+++ 921-page-swap-cache-pageflag.patch-new/include/linux/page-flags.h	2007-07-23 22:13:18.000000000 +1000
@@ -260,9 +260,10 @@ static inline void __ClearPageTail(struc
 #define __ClearPageHead(page)	__ClearPageCompound(page)
 
 #ifdef CONFIG_SWAP
-#define PageSwapCache(page)	test_bit(PG_swapcache, &(page)->flags)
-#define SetPageSwapCache(page)	set_bit(PG_swapcache, &(page)->flags)
-#define ClearPageSwapCache(page) clear_bit(PG_swapcache, &(page)->flags)
+extern struct dyn_pageflags dyn_SwapCache_map;
+#define PageSwapCache(page)	test_dynpageflag(&dyn_SwapCache_map, page)
+#define SetPageSwapCache(page)	set_dynpageflag(&dyn_SwapCache_map, page)
+#define ClearPageSwapCache(page)	clear_dynpageflag(&dyn_SwapCache_map, page)
 #else
 #define PageSwapCache(page)	0
 #endif
diff -ruNp 921-page-swap-cache-pageflag.patch-old/mm/dyn_pageflags.c 921-page-swap-cache-pageflag.patch-new/mm/dyn_pageflags.c
--- 921-page-swap-cache-pageflag.patch-old/mm/dyn_pageflags.c	2007-07-23 22:13:16.000000000 +1000
+++ 921-page-swap-cache-pageflag.patch-new/mm/dyn_pageflags.c	2007-07-23 22:13:18.000000000 +1000
@@ -114,6 +114,9 @@ static int dyn_pageflags_debug = 0;
 		for (zone_nr = 0; zone_nr < MAX_NR_ZONES; zone_nr++)
 
 DECLARE_DYN_PAGEFLAGS(dyn_MappedToDisk_map);
+#ifdef CONFIG_SWAP
+DECLARE_DYN_PAGEFLAGS(dyn_SwapCache_map);
+#endif
 
 /**
  * dump_pagemap: Display the contents of a bitmap for debugging purposes.