On Fri, Dec 08, 2017 at 06:13:43PM +0800, [email protected] wrote:
> From: Lihao Liang <[email protected]>
>
> This commit adds support of the qemu command qemu-system-aarch64
> to rcutorture. Use the following command to run:
>
> ./kvm.sh --qemu-cmd qemu-system-aarch64
>
> Signed-off-by: Lihao Liang <[email protected]>
Nice!!! Getting ARM support for rcutorture has been on my todo list
for some time!
A few questions and comments below.
Feedback from ARM experts also welcome!
Thanx, Paul
> ---
>
> The max CPUs supported by qemu machine 'virt' is 8 so the value of
> CONFIG_NR_CPUS in some test configuration files needs to be adjusted.
>
> tools/testing/selftests/rcutorture/bin/functions.sh | 18 +++++++++++++++++-
> 1 file changed, 17 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/rcutorture/bin/functions.sh
> b/tools/testing/selftests/rcutorture/bin/functions.sh
> index 07a1377..5ffe4fe 100644
> --- a/tools/testing/selftests/rcutorture/bin/functions.sh
> +++ b/tools/testing/selftests/rcutorture/bin/functions.sh
> @@ -136,6 +136,9 @@ identify_boot_image () {
> qemu-system-x86_64|qemu-system-i386)
> echo arch/x86/boot/bzImage
> ;;
> + qemu-system-aarch64)
> + echo arch/arm64/boot/Image
> + ;;
> *)
> echo vmlinux
> ;;
Is it possible to automatically select ARM based on the kernel binary?
See the identify_qemu function for how this is done for i386, x86_64,
and PowerPC. Can an "elif" be added for ARM?
> @@ -185,7 +188,14 @@ identify_qemu_append () {
> then
> echo root=/dev/sda
> else
> - echo console=ttyS0
> + case "$1" in
> + qemu-system-aarch64)
> + echo console=ttyAMA0
> + ;;
> + *)
> + echo console=ttyS0
> + ;;
> + esac
> fi
> }
This approach is going to result in very ugly nesting if support is
added for additional CPU families. How about something like this?
identify_qemu_append () {
local console=ttyS0
case "$1" in
qemu-system-x86_64|qemu-system-i386)
echo noapic selinux=0 initcall_debug debug
;;
qemu-system-aarch64)
console=ttyAMA0
;;
esac
if test -n "$TORTURE_QEMU_INTERACTIVE"
then
echo root=/dev/sda
else
echo console=$console
fi
}
> @@ -197,6 +207,9 @@ identify_qemu_args () {
> case "$1" in
> qemu-system-x86_64|qemu-system-i386)
> ;;
> + qemu-system-aarch64)
> + echo -M virt -cpu host
> + ;;
> qemu-system-ppc64)
> echo -enable-kvm -M pseries -nodefaults
> echo -device spapr-vscsi
> @@ -257,6 +270,9 @@ specify_qemu_cpus () {
> qemu-system-x86_64|qemu-system-i386)
How about the following instead, eliminating the need for an additional
case?
qemu-system-x86_64|qemu-system-i386!qemu-system-aarch64)
> echo $2 -smp $3
> ;;
> + qemu-system-aarch64)
> + echo $2 -smp $3
> + ;;
> qemu-system-ppc64)
> nt="`lscpu | grep '^NUMA node0' | sed -e
> 's/^[^,]*,\([0-9]*\),.*$/\1/'`"
> echo $2 -smp cores=`expr \( $3 + $nt - 1 \) /
> $nt`,threads=$nt
> --
> 2.7.4
>
