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

Adrian Bunk
2008-10-29T20:24:25Z

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.
>...

The multiple ARCH settings with different semantics for them are an
x86 curiosity.

But the MIPS, PowerPC and s390 architectures also have unified
32bit/64bit architectures, so whatever you do will most likely
also be required on these architectures.

> -- Steve

cu
Adrian

--

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