pageflags: convert to the use of new macros
authorChristoph Lameter <clameter@sgi.com>
Mon, 28 Apr 2008 09:12:50 +0000 (02:12 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Mon, 28 Apr 2008 15:58:22 +0000 (08:58 -0700)
Replace explicit definitions of page flags through the use of macros.
Significantly reduces the size of the definitions and removes a lot of
opportunity for errors.  Additonal page flags can typically be generated with
a single line.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
include/linux/page-flags.h

index e5bddbfcf7aeef24845939110d3c8386024b26c1..ed7659adfaaf4bfc15ed053223389ec55cc342f9 100644 (file)
@@ -149,28 +149,58 @@ static inline int TestClearPage##uname(struct page *page)         \
 #define TESTSCFLAG(uname, lname)                                       \
        TESTSETFLAG(uname, lname) TESTCLEARFLAG(uname, lname)
 
+struct page;   /* forward declaration */
+
+PAGEFLAG(Locked, locked) TESTSCFLAG(Locked, locked)
+PAGEFLAG(Error, error)
+PAGEFLAG(Referenced, referenced) TESTCLEARFLAG(Referenced, referenced)
+PAGEFLAG(Dirty, dirty) TESTSCFLAG(Dirty, dirty) __CLEARPAGEFLAG(Dirty, dirty)
+PAGEFLAG(LRU, lru) __CLEARPAGEFLAG(LRU, lru)
+PAGEFLAG(Active, active) __CLEARPAGEFLAG(Active, active)
+__PAGEFLAG(Slab, slab)
+PAGEFLAG(Checked, checked)             /* Used by some filesystems */
+PAGEFLAG(Pinned, pinned)               /* Xen pinned pagetable */
+PAGEFLAG(Reserved, reserved) __CLEARPAGEFLAG(Reserved, reserved)
+PAGEFLAG(Private, private) __CLEARPAGEFLAG(Private, private)
+       __SETPAGEFLAG(Private, private)
+
+/*
+ * Only test-and-set exist for PG_writeback.  The unconditional operators are
+ * risky: they bypass page accounting.
+ */
+TESTPAGEFLAG(Writeback, writeback) TESTSCFLAG(Writeback, writeback)
+__PAGEFLAG(Buddy, buddy)
+PAGEFLAG(MappedToDisk, mappedtodisk)
+
+/* PG_readahead is only used for file reads; PG_reclaim is only for writes */
+PAGEFLAG(Reclaim, reclaim) TESTCLEARFLAG(Reclaim, reclaim)
+PAGEFLAG(Readahead, readahead)         /* Reminder to do async read-ahead */
+
+#ifdef CONFIG_HIGHMEM
 /*
- * Manipulation of page state flags
+ * Must use a macro here due to header dependency issues. page_zone() is not
+ * available at this point.
  */
-#define PageLocked(page)               \
-               test_bit(PG_locked, &(page)->flags)
-#define SetPageLocked(page)            \
-               set_bit(PG_locked, &(page)->flags)
-#define TestSetPageLocked(page)                \
-               test_and_set_bit(PG_locked, &(page)->flags)
-#define ClearPageLocked(page)          \
-               clear_bit(PG_locked, &(page)->flags)
-#define TestClearPageLocked(page)      \
-               test_and_clear_bit(PG_locked, &(page)->flags)
-
-#define PageError(page)                test_bit(PG_error, &(page)->flags)
-#define SetPageError(page)     set_bit(PG_error, &(page)->flags)
-#define ClearPageError(page)   clear_bit(PG_error, &(page)->flags)
-
-#define PageReferenced(page)   test_bit(PG_referenced, &(page)->flags)
-#define SetPageReferenced(page)        set_bit(PG_referenced, &(page)->flags)
-#define ClearPageReferenced(page)      clear_bit(PG_referenced, &(page)->flags)
-#define TestClearPageReferenced(page) test_and_clear_bit(PG_referenced, &(page)->flags)
+#define PageHighMem(__p) is_highmem(page_zone(page))
+#else
+static inline int PageHighMem(struct page *page)
+{
+       return 0;
+}
+#endif
+
+#ifdef CONFIG_SWAP
+PAGEFLAG(SwapCache, swapcache)
+#else
+static inline int PageSwapCache(struct page *page)
+{
+       return 0;
+}
+#endif
+
+#if (BITS_PER_LONG > 32)
+PAGEFLAG(Uncached, uncached)
+#endif
 
 static inline int PageUptodate(struct page *page)
 {
@@ -218,97 +248,37 @@ static inline void SetPageUptodate(struct page *page)
 #endif
 }
 
-#define ClearPageUptodate(page)        clear_bit(PG_uptodate, &(page)->flags)
-
-#define PageDirty(page)                test_bit(PG_dirty, &(page)->flags)
-#define SetPageDirty(page)     set_bit(PG_dirty, &(page)->flags)
-#define TestSetPageDirty(page) test_and_set_bit(PG_dirty, &(page)->flags)
-#define ClearPageDirty(page)   clear_bit(PG_dirty, &(page)->flags)
-#define __ClearPageDirty(page) __clear_bit(PG_dirty, &(page)->flags)
-#define TestClearPageDirty(page) test_and_clear_bit(PG_dirty, &(page)->flags)
-
-#define PageLRU(page)          test_bit(PG_lru, &(page)->flags)
-#define SetPageLRU(page)       set_bit(PG_lru, &(page)->flags)
-#define ClearPageLRU(page)     clear_bit(PG_lru, &(page)->flags)
-#define __ClearPageLRU(page)   __clear_bit(PG_lru, &(page)->flags)
-
-#define PageActive(page)       test_bit(PG_active, &(page)->flags)
-#define SetPageActive(page)    set_bit(PG_active, &(page)->flags)
-#define ClearPageActive(page)  clear_bit(PG_active, &(page)->flags)
-#define __ClearPageActive(page)        __clear_bit(PG_active, &(page)->flags)
-
-#define PageSlab(page)         test_bit(PG_slab, &(page)->flags)
-#define __SetPageSlab(page)    __set_bit(PG_slab, &(page)->flags)
-#define __ClearPageSlab(page)  __clear_bit(PG_slab, &(page)->flags)
-
-#ifdef CONFIG_HIGHMEM
-#define PageHighMem(page)      is_highmem(page_zone(page))
-#else
-#define PageHighMem(page)      0 /* needed to optimize away at compile time */
-#endif
-
-#define PageChecked(page)      test_bit(PG_checked, &(page)->flags)
-#define SetPageChecked(page)   set_bit(PG_checked, &(page)->flags)
-#define ClearPageChecked(page) clear_bit(PG_checked, &(page)->flags)
-
-#define PagePinned(page)       test_bit(PG_pinned, &(page)->flags)
-#define SetPagePinned(page)    set_bit(PG_pinned, &(page)->flags)
-#define ClearPagePinned(page)  clear_bit(PG_pinned, &(page)->flags)
-
-#define PageReserved(page)     test_bit(PG_reserved, &(page)->flags)
-#define SetPageReserved(page)  set_bit(PG_reserved, &(page)->flags)
-#define ClearPageReserved(page)        clear_bit(PG_reserved, &(page)->flags)
-#define __ClearPageReserved(page)      __clear_bit(PG_reserved, &(page)->flags)
-
-#define SetPagePrivate(page)   set_bit(PG_private, &(page)->flags)
-#define ClearPagePrivate(page) clear_bit(PG_private, &(page)->flags)
-#define PagePrivate(page)      test_bit(PG_private, &(page)->flags)
-#define __SetPagePrivate(page)  __set_bit(PG_private, &(page)->flags)
-#define __ClearPagePrivate(page) __clear_bit(PG_private, &(page)->flags)
+CLEARPAGEFLAG(Uptodate, uptodate)
 
-/*
- * Only test-and-set exist for PG_writeback.  The unconditional operators are
- * risky: they bypass page accounting.
- */
-#define PageWriteback(page)    test_bit(PG_writeback, &(page)->flags)
-#define TestSetPageWriteback(page) test_and_set_bit(PG_writeback,      \
-                                                       &(page)->flags)
-#define TestClearPageWriteback(page) test_and_clear_bit(PG_writeback,  \
-                                                       &(page)->flags)
-
-#define PageBuddy(page)                test_bit(PG_buddy, &(page)->flags)
-#define __SetPageBuddy(page)   __set_bit(PG_buddy, &(page)->flags)
-#define __ClearPageBuddy(page) __clear_bit(PG_buddy, &(page)->flags)
-
-#define PageMappedToDisk(page) test_bit(PG_mappedtodisk, &(page)->flags)
-#define SetPageMappedToDisk(page) set_bit(PG_mappedtodisk, &(page)->flags)
-#define ClearPageMappedToDisk(page) clear_bit(PG_mappedtodisk, &(page)->flags)
+extern void cancel_dirty_page(struct page *page, unsigned int account_size);
 
-#define PageReadahead(page)    test_bit(PG_readahead, &(page)->flags)
-#define SetPageReadahead(page) set_bit(PG_readahead, &(page)->flags)
-#define ClearPageReadahead(page) clear_bit(PG_readahead, &(page)->flags)
+int test_clear_page_writeback(struct page *page);
+int test_set_page_writeback(struct page *page);
 
-#define PageReclaim(page)      test_bit(PG_reclaim, &(page)->flags)
-#define SetPageReclaim(page)   set_bit(PG_reclaim, &(page)->flags)
-#define ClearPageReclaim(page) clear_bit(PG_reclaim, &(page)->flags)
-#define TestClearPageReclaim(page) test_and_clear_bit(PG_reclaim, &(page)->flags)
+static inline void set_page_writeback(struct page *page)
+{
+       test_set_page_writeback(page);
+}
 
-#define PageCompound(page)     test_bit(PG_compound, &(page)->flags)
-#define __SetPageCompound(page)        __set_bit(PG_compound, &(page)->flags)
-#define __ClearPageCompound(page) __clear_bit(PG_compound, &(page)->flags)
+TESTPAGEFLAG(Compound, compound)
+__PAGEFLAG(Head, compound)
 
 /*
  * PG_reclaim is used in combination with PG_compound to mark the
- * head and tail of a compound page
+ * head and tail of a compound page. This saves one page flag
+ * but makes it impossible to use compound pages for the page cache.
+ * The PG_reclaim bit would have to be used for reclaim or readahead
+ * if compound pages enter the page cache.
  *
  * PG_compound & PG_reclaim    => Tail page
  * PG_compound & ~PG_reclaim   => Head page
  */
-
 #define PG_head_tail_mask ((1L << PG_compound) | (1L << PG_reclaim))
 
-#define PageTail(page) (((page)->flags & PG_head_tail_mask)    \
-                               == PG_head_tail_mask)
+static inline int PageTail(struct page *page)
+{
+       return ((page->flags & PG_head_tail_mask) == PG_head_tail_mask);
+}
 
 static inline void __SetPageTail(struct page *page)
 {
@@ -320,34 +290,5 @@ static inline void __ClearPageTail(struct page *page)
        page->flags &= ~PG_head_tail_mask;
 }
 
-#define PageHead(page) (((page)->flags & PG_head_tail_mask)    \
-                               == (1L << PG_compound))
-#define __SetPageHead(page)    __SetPageCompound(page)
-#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)
-#else
-#define PageSwapCache(page)    0
-#endif
-
-#define PageUncached(page)     test_bit(PG_uncached, &(page)->flags)
-#define SetPageUncached(page)  set_bit(PG_uncached, &(page)->flags)
-#define ClearPageUncached(page)        clear_bit(PG_uncached, &(page)->flags)
-
-struct page;   /* forward declaration */
-
-extern void cancel_dirty_page(struct page *page, unsigned int account_size);
-
-int test_clear_page_writeback(struct page *page);
-int test_set_page_writeback(struct page *page);
-
-static inline void set_page_writeback(struct page *page)
-{
-       test_set_page_writeback(page);
-}
-
 #endif /* !__GENERATING_BOUNDS_H */
 #endif /* PAGE_FLAGS_H */