Re: [PATCH bpf-next v2 1/2] bpf: Helper script for running BPF presubmit tests

[Jiri Olsa <jolsa@redhat.com>]

On Sat, Jan 23, 2021 at 12:44:44AM +0000, KP Singh wrote:
> The script runs the BPF selftests locally on the same kernel image
> as they would run post submit in the BPF continuous integration
> framework.
> 
> The goal of the script is to allow contributors to run selftests locally
> in the same environment to check if their changes would end up breaking
> the BPF CI and reduce the back-and-forth between the maintainers and the
> developers.
> 
> Signed-off-by: KP Singh <kpsingh@kernel.org>

great! thanks for this

Tested-by: Jiri Olsa <jolsa@redhat.com>

jirka

> ---
>  tools/testing/selftests/bpf/run_in_vm.sh | 353 +++++++++++++++++++++++
>  1 file changed, 353 insertions(+)
>  create mode 100755 tools/testing/selftests/bpf/run_in_vm.sh
> 
> diff --git a/tools/testing/selftests/bpf/run_in_vm.sh b/tools/testing/selftests/bpf/run_in_vm.sh
> new file mode 100755
> index 000000000000..09bb9705acb3
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/run_in_vm.sh
> @@ -0,0 +1,353 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +
> +set -u
> +set -e
> +
> +QEMU_BINARY="${QEMU_BINARY:="qemu-system-x86_64"}"
> +X86_BZIMAGE="arch/x86/boot/bzImage"
> +DEFAULT_COMMAND="./test_progs"
> +MOUNT_DIR="mnt"
> +ROOTFS_IMAGE="root.img"
> +OUTPUT_DIR="$HOME/.bpf_selftests"
> +KCONFIG_URL="https://raw.githubusercontent.com/libbpf/libbpf/master/travis-ci/vmtest/configs/latest.config"
> +INDEX_URL="https://raw.githubusercontent.com/libbpf/libbpf/master/travis-ci/vmtest/configs/INDEX"
> +NUM_COMPILE_JOBS="$(nproc)"
> +
> +usage()
> +{
> +	cat <<EOF
> +Usage: $0 [-k] [-i] [-d <output_dir>] -- [<command>]
> +
> +<command> is the command you would normally run when you are in
> +tools/testing/selftests/bpf. e.g:
> +
> +	$0 -- ./test_progs -t test_lsm
> +
> +If no command is specified, "${DEFAULT_COMMAND}" will be run by
> +default.
> +
> +If you build your kernel using KBUILD_OUTPUT= or O= options, these
> +can be passed as environment variables to the script:
> +
> +  O=<path_relative_to_cwd> $0 -- ./test_progs -t test_lsm
> +
> +or
> +
> +  KBUILD_OUTPUT=<path_relative_to_cwd> $0 -- ./test_progs -t test_lsm
> +
> +Options:
> +
> +	-k)		"Keep the kernel", i.e. don't recompile the kernel if it exists.
> +	-i)		Update the rootfs image with a newer version.
> +	-d)		Update the output directory (default: ${OUTPUT_DIR})
> +	-j)		Number of jobs for compilation, similar to -j in make
> +			(default: ${NUM_COMPILE_JOBS})
> +EOF
> +}
> +
> +unset URLS
> +populate_url_map()
> +{
> +	if ! declare -p URLS &> /dev/null; then
> +		# URLS contain the mapping from file names to URLs where
> +		# those files can be downloaded from.
> +		declare -gA URLS
> +		while IFS=$'\t' read -r name url; do
> +			URLS["$name"]="$url"
> +		done < <(curl -Lsf ${INDEX_URL})
> +	fi
> +	echo "${URLS[*]}"
> +}
> +
> +download()
> +{
> +	local file="$1"
> +
> +	if [[ ! -v URLS[$file] ]]; then
> +		echo "$file not found" >&2
> +		return 1
> +	fi
> +
> +	echo "Downloading $file..." >&2
> +	curl -Lf "${URLS[$file]}" "${@:2}"
> +}
> +
> +newest_rootfs_version()
> +{
> +	{
> +	for file in "${!URLS[@]}"; do
> +		if [[ $file =~ ^libbpf-vmtest-rootfs-(.*)\.tar\.zst$ ]]; then
> +			echo "${BASH_REMATCH[1]}"
> +		fi
> +	done
> +	} | sort -rV | head -1
> +}
> +
> +download_rootfs()
> +{
> +	local rootfsversion="$1"
> +	local dir="$2"
> +
> +	if ! which zstd &> /dev/null; then
> +		echo 'Could not find "zstd" on the system, please install zstd'
> +		exit 1
> +	fi
> +
> +	download "libbpf-vmtest-rootfs-$rootfsversion.tar.zst" |
> +		zstd -d | sudo tar -C "$dir" -x
> +}
> +
> +recompile_kernel()
> +{
> +	local kernel_checkout="$1"
> +	local make_command="$2"
> +
> +	cd "${kernel_checkout}"
> +
> +	${make_command} olddefconfig
> +	${make_command}
> +}
> +
> +mount_image()
> +{
> +	local rootfs_img="${OUTPUT_DIR}/${ROOTFS_IMAGE}"
> +	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"
> +
> +	sudo mount -o loop "${rootfs_img}" "${mount_dir}"
> +}
> +
> +unmount_image()
> +{
> +	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"
> +
> +	sudo umount "${mount_dir}" &> /dev/null
> +}
> +
> +update_selftests()
> +{
> +	local kernel_checkout="$1"
> +	local selftests_dir="${kernel_checkout}/tools/testing/selftests/bpf"
> +
> +	cd "${selftests_dir}"
> +	${make_command}
> +
> +	# Mount the image and copy the selftests to the image.
> +	mount_image
> +	sudo rm -rf "${mount_dir}/root/bpf"
> +	sudo cp -r "${selftests_dir}" "${mount_dir}/root"
> +	unmount_image
> +}
> +
> +update_init_script()
> +{
> +	local init_script_dir="${OUTPUT_DIR}/${MOUNT_DIR}/etc/rcS.d"
> +	local init_script="${init_script_dir}/S50-startup"
> +	local command="$1"
> +	local log_file="$2"
> +
> +	mount_image
> +
> +	if [[ ! -d "${init_script_dir}" ]]; then
> +		cat <<EOF
> +Could not find ${init_script_dir} in the mounted image.
> +This likely indicates a bad rootfs image, Please download
> +a new image by passing "-i" to the script
> +EOF
> +		exit 1
> +
> +	fi
> +
> +	cat <<EOF | sudo tee "${init_script}"
> +#!/bin/bash
> +
> +{
> +
> +	cd /root/bpf
> +	echo ${command}
> +	${command}
> +} 2>&1 | tee /root/${log_file}
> +poweroff -f
> +EOF
> +
> +	sudo chmod a+x "${init_script}"
> +	unmount_image
> +}
> +
> +create_vm_image()
> +{
> +	local rootfs_img="${OUTPUT_DIR}/${ROOTFS_IMAGE}"
> +	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"
> +
> +	rm -rf "${rootfs_img}"
> +	touch "${rootfs_img}"
> +	chattr +C "${rootfs_img}" >/dev/null 2>&1 || true
> +
> +	truncate -s 2G "${rootfs_img}"
> +	mkfs.ext4 -q "${rootfs_img}"
> +
> +	mount_image
> +	download_rootfs "$(newest_rootfs_version)" "${mount_dir}"
> +	unmount_image
> +}
> +
> +run_vm()
> +{
> +	local kernel_bzimage="$1"
> +	local rootfs_img="${OUTPUT_DIR}/${ROOTFS_IMAGE}"
> +
> +	if ! which "${QEMU_BINARY}" &> /dev/null; then
> +		cat <<EOF
> +Could not find ${QEMU_BINARY}
> +Please install qemu or set the QEMU_BINARY environment variable.
> +EOF
> +		exit 1
> +	fi
> +
> +	${QEMU_BINARY} \
> +		-nodefaults \
> +		-display none \
> +		-serial mon:stdio \
> +		-cpu kvm64 \
> +		-enable-kvm \
> +		-smp 4 \
> +		-m 2G \
> +		-drive file="${rootfs_img}",format=raw,index=1,media=disk,if=virtio,cache=none \
> +		-kernel "${kernel_bzimage}" \
> +		-append "root=/dev/vda rw console=ttyS0,115200"
> +}
> +
> +copy_logs()
> +{
> +	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"
> +	local log_file="${mount_dir}/root/$1"
> +
> +	mount_image
> +	sudo cp ${log_file} "${OUTPUT_DIR}"
> +	sudo rm -f ${log_file}
> +	unmount_image
> +}
> +
> +is_rel_path()
> +{
> +	local path="$1"
> +
> +	[[ ${path:0:1} != "/" ]]
> +}
> +
> +main()
> +{
> +	local script_dir="$(cd -P -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd -P)"
> +	local kernel_checkout=$(realpath "${script_dir}"/../../../../)
> +	local log_file="$(date +"bpf_selftests.%Y-%m-%d_%H-%M-%S.log")"
> +	# By default the script searches for the kernel in the checkout directory but
> +	# it also obeys environment variables O= and KBUILD_OUTPUT=
> +	local kernel_bzimage="${kernel_checkout}/${X86_BZIMAGE}"
> +	local command="${DEFAULT_COMMAND}"
> +	local kernel_recompile="yes"
> +	local update_image="no"
> +
> +	while getopts 'hkid:j:' opt; do
> +		case ${opt} in
> +		k)
> +			kernel_recompile="no"
> +			;;
> +		i)
> +			update_image="yes"
> +			;;
> +		d)
> +			OUTPUT_DIR="$OPTARG"
> +			;;
> +		j)
> +			NUM_COMPILE_JOBS="$OPTARG"
> +			;;
> +		h)
> +			usage
> +			exit 0
> +			;;
> +		\? )
> +			echo "Invalid Option: -$OPTARG"
> +			usage
> +			exit 1
> +			;;
> +      		: )
> +        		echo "Invalid Option: -$OPTARG requires an argument"
> +			usage
> +			exit 1
> +			;;
> +		esac
> +	done
> +	shift $((OPTIND -1))
> +
> +	if [[ $# -eq 0 ]]; then
> +		echo "No command specified, will run ${DEFAULT_COMMAND} in the vm"
> +	else
> +		command="$@"
> +	fi
> +
> +	local kconfig_file="${OUTPUT_DIR}/latest.config"
> +	local make_command="make -j ${NUM_COMPILE_JOBS} KCONFIG_CONFIG=${kconfig_file}"
> +
> +	# Figure out where the kernel is being built.
> +	# O takes precedence over KBUILD_OUTPUT.
> +	if [[ "${O:=""}" != "" ]]; then
> +		if is_rel_path "${O}"; then
> +			O="$(realpath "${PWD}/${O}")"
> +		fi
> +		kernel_bzimage="${O}/${X86_BZIMAGE}"
> +		make_command="${make_command} O=${O}"
> +	elif [[ "${KBUILD_OUTPUT:=""}" != "" ]]; then
> +		if is_rel_path "${KBUILD_OUTPUT}"; then
> +			KBUILD_OUTPUT="$(realpath "${PWD}/${KBUILD_OUTPUT}")"
> +		fi
> +		kernel_bzimage="${KBUILD_OUTPUT}/${X86_BZIMAGE}"
> +		make_command="${make_command} KBUILD_OUTPUT=${KBUILD_OUTPUT}"
> +	fi
> +
> +	populate_url_map
> +
> +	local rootfs_img="${OUTPUT_DIR}/${ROOTFS_IMAGE}"
> +	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"
> +
> +	echo "Output directory: ${OUTPUT_DIR}"
> +
> +	mkdir -p "${OUTPUT_DIR}"
> +	mkdir -p "${mount_dir}"
> +	curl -Lf "${KCONFIG_URL}" -o "${kconfig_file}"
> +
> +	if [[ "${kernel_recompile}" == "no" && ! -f "${kernel_bzimage}" ]]; then
> +		echo "Kernel image not found in ${kernel_bzimage}, kernel will be recompiled"
> +		kernel_recompile="yes"
> +	fi
> +
> +	if [[ "${kernel_recompile}" == "yes" ]]; then
> +		recompile_kernel "${kernel_checkout}" "${make_command}"
> +	fi
> +
> +	if [[ "${update_image}" == "no" && ! -f "${rootfs_img}" ]]; then
> +		echo "rootfs image not found in ${rootfs_img}"
> +		update_image="yes"
> +	fi
> +
> +	if [[ "${update_image}" == "yes" ]]; then
> +		create_vm_image
> +	fi
> +
> +	update_selftests "${kernel_checkout}" "${make_command}"
> +	update_init_script "${command}" "${log_file}"
> +	run_vm "${kernel_bzimage}"
> +	copy_logs "${log_file}"
> +	echo "Logs saved in ${OUTPUT_DIR}/${log_file}"
> +}
> +
> +catch()
> +{
> +	local exit_code=$1
> +
> +	unmount_image
> +	exit ${exit_code}
> +}
> +
> +trap 'catch "$?"' EXIT
> +
> +main "$@"
> -- 
> 2.30.0.280.ga3ce27912f-goog
>