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>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
#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
};