2008-03-01 04:07:46

by Christoph Lameter

[permalink] [raw]
Subject: [rfc 02/10] Pageflags: Introduce macros to generate page flag functions

Introduce a set of macros that generate functions to handle page flags.


A page flag function group typically starts with either

SETPAGEFLAG(<part of function name>,<part of PG_ flagname>)

to create a set of page flag operations that are atomic. Or

__SETPAGEFLAG(<part of function name>,<part of PG_ flagname)

to create a set of page flag operations that are not atomic.


Then additional operations can be added using the following macros

TESTSCFLAG Create additional atomic test-and-set and
test-and-clear functions

TESTSETFLAG Create additional test and set function
TESTCLEARFLAG Create additional test and clear function
TESTPAGEFLAG Create additional atomic set function
SETPAGEFLAG Create additional atomic clear function
__TESTPAGEFLAG Create additional atomic set function
__SETPAGEFLAG Create additional atomic clear function

Signed-off-by: Christoph Lameter <[email protected]>

---
include/linux/page-flags.h | 41 +++++++++++++++++++++++++++++++++++++++++
1 file changed, 41 insertions(+)

Index: linux-2.6/include/linux/page-flags.h
===================================================================
--- linux-2.6.orig/include/linux/page-flags.h 2008-02-29 19:14:30.000000000 -0800
+++ linux-2.6/include/linux/page-flags.h 2008-02-29 19:15:28.000000000 -0800
@@ -103,6 +103,47 @@ enum pageflags {
};

/*
+ * Macros to create function definitions for page flags
+ */
+#define TESTPAGEFLAG(uname, lname) \
+static inline int Page##uname(struct page *page) \
+ { return test_bit(PG_##lname, page); }
+
+#define SETPAGEFLAG(uname, lname) \
+static inline void SetPage##uname(struct page *page) \
+ { set_bit(PG_##lname, page); }
+
+#define CLEARPAGEFLAG(uname, lname) \
+static inline void ClearPage##uname(struct page *page) \
+ { clear_bit(PG_##lname, page); }
+
+#define __SETPAGEFLAG(uname, lname) \
+static inline void __SetPage##uname(struct page *page) \
+ { __set_bit(PG_##lname, page); }
+
+#define __CLEARPAGEFLAG(uname, lname) \
+static inline void __ClearPage##uname(struct page *page) \
+ { __clear_bit(PG_##lname, page); }
+
+#define TESTSETFLAG(uname, lname) \
+static inline int TestSetPage##uname(struct page *page) \
+ { return test_and_set_bit(PG_##lname, &page->flags); }
+
+#define TESTCLEARFLAG(uname, lname) \
+static inline int TestClearPage##uname(struct page *page) \
+ { return test_and_clear_bit(PG_##lname, &page->flags); }
+
+
+#define PAGEFLAG(uname, lname) TESTPAGEFLAG(uname, lname) \
+ SETPAGEFLAG(uname, lname) CLEARPAGEFLAG(uname, lname)
+
+#define __PAGEFLAG(uname, lname) TESTPAGEFLAG(uname, lname) \
+ __SETPAGEFLAG(uname, lname) __CLEARPAGEFLAG(uname, lname)
+
+#define TESTSCFLAG(uname, lname) \
+ TESTSETFLAG(uname, lname) TESTCLEARFLAG(uname, lname)
+
+/*
* Manipulation of page state flags
*/
#define PageLocked(page) \

--