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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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