Hi Drew,
On Mon, Jan 13, 2025 at 04:11:06PM +0100, Andrew Jones wrote:
> On Fri, Jan 10, 2025 at 01:58:45PM +0000, Alexandru Elisei wrote:
> > The help text for the --processor option displays the architecture name as
> > the default processor type. But the default for arm is cortex-a15, and for
> > arm64 is cortex-a57. Teach configure to display the correct default
> > processor type for these two architectures.
> >
> > Signed-off-by: Alexandru Elisei <alexandru.elisei@xxxxxxx>
> > ---
> > configure | 30 ++++++++++++++++++++++--------
> > 1 file changed, 22 insertions(+), 8 deletions(-)
> >
> > diff --git a/configure b/configure
> > index 5b0a2d7f39c0..138840c3f76d 100755
> > --- a/configure
> > +++ b/configure
> > @@ -5,6 +5,24 @@ if [ -z "${BASH_VERSINFO[0]}" ] || [ "${BASH_VERSINFO[0]}" -lt 4 ] ; then
> > exit 1
> > fi
> >
> > +function get_default_processor()
> > +{
> > + local arch="$1"
> > +
> > + case "$arch" in
> > + "arm")
> > + default_processor="cortex-a15"
> > + ;;
> > + "arm64" | "aarch64")
> > + default_processor="cortex-a57"
> > + ;;
> > + *)
> > + default_processor=$arch
> > + esac
> > +
> > + echo "$default_processor"
> > +}
> > +
> > srcdir=$(cd "$(dirname "$0")"; pwd)
> > prefix=/usr/local
> > cc=gcc
> > @@ -33,6 +51,7 @@ page_size=
> > earlycon=
> > efi=
> > efi_direct=
> > +default_processor=$(get_default_processor $arch)
> >
> > # Enable -Werror by default for git repositories only (i.e. developer builds)
> > if [ -e "$srcdir"/.git ]; then
> > @@ -48,7 +67,7 @@ usage() {
> > Options include:
> > --arch=ARCH architecture to compile for ($arch). ARCH can be one of:
> > arm, arm64/aarch64, i386, ppc64, riscv32, riscv64, s390x, x86_64
> > - --processor=PROCESSOR processor to compile for ($arch)
> > + --processor=PROCESSOR processor to compile for ($default_processor)
> > --target=TARGET target platform that the tests will be running on (qemu or
> > kvmtool, default is qemu) (arm/arm64 only)
> > --cross-prefix=PREFIX cross compiler prefix
> > @@ -283,13 +302,8 @@ else
> > fi
> > fi
> >
> > -[ -z "$processor" ] && processor="$arch"
> > -
> > -if [ "$processor" = "arm64" ]; then
> > - processor="cortex-a57"
> > -elif [ "$processor" = "arm" ]; then
> > - processor="cortex-a15"
> > -fi
> > +# $arch will have changed when cross-compiling.
> > +[ -z "$processor" ] && processor=$(get_default_processor $arch)
>
> The fact that $arch and $processor are wrong until they've had a chance to
$processor is never wrong. $processor is unset until either the user sets it
with --processor, or until this line. This patch introduces $default_processor
only for the purpose of having an accurate help text, it doesn't change when and
how $processor is assigned.
> be converted might be another reason for the $do_help idea. But it'll
> always be fragile since another change that does some sort of conversion
> could end up getting added after the '[ $do_help ] && usage' someday.
configure needs to distinguish between:
1. The user not having specified --processor when doing ./configure.
2. The user having set --processor.
If 1, then kvm-unit-tests can use the default $processor value for $arch,
which could have also been specified by the user.
If 2, then kvm-unit-tests should not touch $processor because that's what the
user wants.
Do you see something wrong with that reasoning?
Also, I don't understand why you say it's fragile, since configure doesn't
touch $processor until this point (and unless the user sets it, of course).
Thanks,
Alex
