Subject: RE: Do LKMs work *at*all* on powerpc platforms?
To: None <>
From: Todd Vierling <>
List: port-powerpc
Date: 08/07/2000 21:15:13
On Mon, 7 Aug 2000, Bill Studenmund wrote:

: > > I think adding something like -mlong-call and __attribute__ ((short-call))
: > > would be the most efficient thing. :-)

(Note that I do have the ppc ref manuals, but I stepped into the thread
late; I subscribed to port-macppc a week ago.)

Exactly how much overhead are we looking at between longcall and shortcall
here?  I just want to know how many CPU cycles we're anticipating for the
difference in calling convention, and whether it could be worth doing
-mlong-call universally, or just as a documented prerequisite for
LKM-capable kernels.  You could have something like:

#options 	LKM			# loadable kernel modules
#makeoptions	COPTS="-mlong-call"	# required for LKMs to work

in the GENERIC config file, documenting the specific need.  Note that COPTS
here is only an example; you'd probably want to invent a new make variable
name (CALLTYPE?) specifically for this purpose.

-- Todd Vierling <>  *
-- Speed, stability, security, and support.  Wasabi NetBSD:  Run with it.