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Subject[PATCH 4/10] x86 boot: simplify pageblock_bits enum declaration
From: Paul Jackson <pj@sgi.com>

The use of #defines with '##' pre-processor concatenation is a useful
way to form several symbol names with a common pattern. But when there
is just a single name obtained from that #define, it's just obfuscation.
Better to just write the plain symbol name, as is.

The following patch is a result of my wasting ten minutes looking through
the kernel to figure out what 'PB_migrate_end' meant, and forgetting what
I came to do, by the time I figured out that the #define PB_range macro
defined it.

Signed-off-by: Paul Jackson <pj@sgi.com>

---
include/linux/pageblock-flags.h | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
--- linux.orig/include/linux/pageblock-flags.h 2008-05-13 05:42:39.869811856 -0700
+++ linux/include/linux/pageblock-flags.h 2008-05-13 05:51:47.994829315 -0700
@@ -25,13 +25,11 @@

#include <linux/types.h>

-/* Macro to aid the definition of ranges of bits */
-#define PB_range(name, required_bits) \
- name, name ## _end = (name + required_bits) - 1
-
/* Bit indices that affect a whole block of pages */
enum pageblock_bits {
- PB_range(PB_migrate, 3), /* 3 bits required for migrate types */
+ PB_migrate,
+ PB_migrate_end = PB_migrate + 3 - 1,
+ /* 3 bits required for migrate types */
NR_PAGEBLOCK_BITS
};

--
I won't rest till it's the best ...
Programmer, Linux Scalability
Paul Jackson <pj@sgi.com> 1.650.933.1373


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