Re: [PATCH 01/11] ftrace: handle generic arch calls

[Adrian Bunk <bunk@kernel.org>]

On Wed, Oct 29, 2008 at 08:49:56PM +0100, Sam Ravnborg wrote:
> On Wed, Oct 29, 2008 at 03:24:19PM -0400, Steven Rostedt wrote:
> > 
> > On Wed, 29 Oct 2008, Sam Ravnborg wrote:
> > > >  
> > > > +if ($arch eq "x86") {
> > > > +    if ($bits == 64) {
> > > > +	$arch = "x86_64";
> > > > +    } else {
> > > > +	$arch = "i386";
> > > > +    }
> > > > +}
> > > > +
> > > >  if ($arch eq "x86_64") {
> > > >      $section_regex = "Disassembly of section";
> > > >      $function_regex = "^([0-9a-fA-F]+)\\s+<(.*?)>:";
> > > > 
> > > 
> > > This looks strange to my eyes.
> > > Why not do the more obvious:
> > > if ($arch eq "x86" && $bits == 64) {
> > > 
> > > The change above is like trying to stick to the old i386/x86_64
> > > notation.
> > 
> > Trying to fix it tells me my answer to why I did it his way ;-)
> > 
> > I have queued patches that will support other archs so x86 is not the
> > only arch that can be used here. But x86 is special, it seems to be the 
> > only arch (that I know of, correct me if I'm wrong) that can compile with
> > multiple archs defined: make ARCH=x86_64, make ARCH=i386, or
> > make ARCH=x86. All are legit.
> > 
> > Now how do we handle this. I've been fine for all my testing to do just 
> > x86_64 and i386 because a normal make of x86 will use automatically set
> > ARCH to i386 or x86_64 depending on the build.
> > 
> > But then Adrian Bunk pointed out that "make ARCH=x86" fails. Now I need to 
> > add a case for x86, but still allow for x86_64 or i386 being passed in.
> > 
> > Since x86 is the ambiguous case, I made it the one that would be converted 
> > to i386 or x86_64 since those could be passed in directly.
> The trick is usually to replace use of ARCH with SRCARCH.

That won't help - what he wants to know is whether he's on 32bit or
on 64bit.

> 	Sam

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed