bpf: Helper script for running BPF presubmit tests

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>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/bpf/20210204194544.3383814-2-kpsingh@kernel.org
This commit is contained in:
KP Singh 2021-02-04 19:45:43 +00:00 committed by Andrii Nakryiko
parent 4c5de12759
commit c9709f5238
1 changed files with 368 additions and 0 deletions

View File

@ -0,0 +1,368 @@
#!/bin/bash
# SPDX-License-Identifier: GPL-2.0
set -u
set -e
# This script currently only works for x86_64, as
# it is based on the VM image used by the BPF CI which is
# x86_64.
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"
KCONFIG_API_URL="https://api.github.com/repos/libbpf/libbpf/contents/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 [-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=<kernel_build_path> $0 -- ./test_progs -t test_lsm
or
KBUILD_OUTPUT=<kernel_build_path> $0 -- ./test_progs -t test_lsm
Options:
-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
}
download()
{
local file="$1"
if [[ ! -v URLS[$file] ]]; then
echo "$file not found" >&2
return 1
fi
echo "Downloading $file..." >&2
curl -Lsf "${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 ${init_script_dir} in the mounted image.
This likely indicates a bad rootfs image, Please download
a new image by passing "-i" to the script
EOF
exit 1
fi
sudo bash -c "cat >${init_script}" <<EOF
#!/bin/bash
{
cd /root/bpf
echo ${command}
stdbuf -oL -eL ${command}
} 2>&1 | tee /root/${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} != "/" ]]
}
update_kconfig()
{
local kconfig_file="$1"
local update_command="curl -sLf ${KCONFIG_URL} -o ${kconfig_file}"
# Github does not return the "last-modified" header when retrieving the
# raw contents of the file. Use the API call to get the last-modified
# time of the kernel config and only update the config if it has been
# updated after the previously cached config was created. This avoids
# unnecessarily compiling the kernel and selftests.
if [[ -f "${kconfig_file}" ]]; then
local last_modified_date="$(curl -sL -D - "${KCONFIG_API_URL}" -o /dev/null | \
grep "last-modified" | awk -F ': ' '{print $2}')"
local remote_modified_timestamp="$(date -d "${last_modified_date}" +"%s")"
local local_creation_timestamp="$(stat -c %Y "${kconfig_file}")"
if [[ "${remote_modified_timestamp}" -gt "${local_creation_timestamp}" ]]; then
${update_command}
fi
else
${update_command}
fi
}
main()
{
local script_dir="$(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 update_image="no"
while getopts 'hkid:j:' opt; do
case ${opt} in
i)
update_image="yes"
;;
d)
OUTPUT_DIR="$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 "${mount_dir}"
update_kconfig "${kconfig_file}"
recompile_kernel "${kernel_checkout}" "${make_command}"
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
# This is just a cleanup and the directory may
# have already been unmounted. So, don't let this
# clobber the error code we intend to return.
unmount_image || true
exit ${exit_code}
}
trap 'catch "$?"' EXIT
main "$@"