Mempolicy flags, as I implemented them in patch 2 in this series, are not
integer constants that are enumerated starting at 0. They are individual
bits that are shifted a pre-defined length and intersected with the
enumerated mode. This allows both the mode and the flags to be stored in
the same object.
Just because enum mempolicy_mode is the equivalent of passing an int in C
is irrelevant; its semantics are that the value is coming from enum
mempolicy_mode. That includes _only_ the mode itself:
enum mempolicy_mode {
MPOL_DEFAULT,
MPOL_BIND,
MPOL_PREFERRED,
MPOL_INTERLEAVE,
MPOL_MAX,
};
And changing the policy member of struct mempolicy to 'enum
mempolicy_mode' instead of 'unsigned short' would increase its size. Not
that it matters, since in the third patch I add a whole nodemask_t, but
it's simply unnecessary. Right now we have the capacity to store 256
individual mempolicy modes (we currently use four) and eight mempolicy
flags with unsigned short.
David
--
