__setup_param(), unique_id and vdso_setup

["Robert P. J. Day" <rpjday@crashcourse.ca>]

  just going through my outstanding list of kernel cleanup pedantry,
and i was reminded of this from include/linux/init.h:

=====
...
#define __setup(str, fn)                                        \
        __setup_param(str, fn, fn, 0)

/* NOTE: fn is as per module_param, not __setup!  Emits warning if fn
 * returns non-zero. */
#define early_param(str, fn)                                    \
        __setup_param(str, fn, fn, 1)
...
=====

  in short, both invocations of __setup_param() use identical second
and third parameters, and a tree-wide grep shows:

$ grep -rw __setup_param *
arch/x86/vdso/vdso32-setup.c:__setup_param("vdso=", vdso32_setup, vdso_setup, 0);
include/linux/init.h:#define __setup_param(str, unique_id, fn, early)                   \
include/linux/init.h:   __setup_param(str, fn, fn, 0)
include/linux/init.h:   __setup_param(str, fn, fn, 1)
include/linux/init.h:#define __setup_param(str, unique_id, fn)  /* nothing */
$

  so apart from that single exception involving "vdso", that macro
could be simplified to just get rid of that third parameter.  is there
something special about the vdso boot-time parm that *requires* it to
be the only boot-time parm in the entire kernel to have a different
unique id?  just curious.  or does that have to be preserved for
out-of-tree builds?

rday
--

========================================================================
Robert P. J. Day                               Waterloo, Ontario, CANADA

        Linux Consulting, Training and Annoying Kernel Pedantry.

Web page:                                          http://crashcourse.ca
Linked In:                             http://www.linkedin.com/in/rpjday
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