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    SubjectRe: memory waste in fs/devices.c/kdevname()
    	From: Riley Williams <>

    My analysis goes like this: kdev_t is a bitfield


    kdev_t is the kernel device type.

    It is (on some machines, like mine) a pointer to a structure
    with certain fields
    [like int major, minor; a bit indicating char/block device;
    values for size, blocksize, hardsect_size, read_ahead;
    a routine that produces a name, etc.]
    On certain more old-fashioned machines it may be an integral type.

    No part of the kernel today is supposed to know anything
    about this type - it is completely opaque - except for kdev_t.h .

    Unfortunately, not everybody keeps the distinction between
    dev_t and kdev_t. In Jan or Feb this year I submitted some patches
    to make the kernel ready for switching to a pointer kdev_t type
    and most were applied, but not the last one.
    (Maybe rightly so - the other patches were clear improvements
    of the code; the last patch was just the introduction of a layer
    of defines to hide the NFS problems behind.)
    Will try one of these days to see how kdev_t cleanliness has
    survived the past year.


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      Last update: 2005-03-22 13:46    [W:0.017 / U:189.168 seconds]
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