test.yml

name: bpf-ci

on:
  pull_request:
  push:
    branches:
      - bpf_base
      - bpf-next_base

env:
  veristat_arch: x86_64
  veristat_toolchain: gcc

concurrency:
  group: ci-test-${{ github.ref_name }}
  cancel-in-progress: true

jobs:

  set-matrix:
    # FIXME: set-matrix is lightweight, run it on any self-hosted machines for kernel-patches org
    # so we do not wait for GH hosted runners when there potentially all are busy because of bpf-rc
    # repo for instance.
    # This could be somehow fixed long term by making this action/workflow re-usable and letting the called
    # specify what to run on.
    runs-on: ${{ github.repository_owner == 'kernel-patches' && 'x86_64' || 'ubuntu-latest' }}
    outputs:
      build-matrix: ${{ steps.set-matrix-impl.outputs.build_matrix }}
      test-matrix: ${{ steps.set-matrix-impl.outputs.test_matrix }}
      veristat-runs-on: ${{ steps.set-matrix-impl.outputs.veristat_runs_on }}
    steps:
      - id: set-matrix-impl
        shell: python3 -I {0}
        run: |
          from json import dumps
          from enum import Enum
          import os

          class Arch(Enum):
            """
            CPU architecture supported by CI.
            """
            aarch64 = "aarch64"
            s390x = "s390x"
            x86_64 = "x86_64"

          def set_output(name, value):
            """Write an output variable to the GitHub output file."""
            with open(os.getenv("GITHUB_OUTPUT"), "a") as f:
              f.write(f"{name}={value}\n")

          def generate_test_config(test):
            """Create the configuration for the provided test."""
            experimental = test.endswith("_parallel")
            config = {
              "test": test,
              "continue_on_error": experimental,
              # While in experimental mode, parallel jobs may get stuck
              # anywhere, including in user space where the kernel won't detect
              # a problem and panic. We add a second layer of (smaller) timeouts
              # here such that if we get stuck in a parallel run, we hit this
              # timeout and fail without affecting the overall job success (as
              # would be the case if we hit the job-wide timeout). For
              # non-experimental jobs, 360 is the default which will be
              # superseded by the overall workflow timeout (but we need to
              # specify something).
              "timeout_minutes": 30 if experimental else 360,
            }
            return config

          matrix = [
            {"kernel": "LATEST", "runs_on": [], "arch": Arch.x86_64.value, "toolchain": "gcc", "llvm-version": "16"},
            {"kernel": "LATEST", "runs_on": [], "arch": Arch.x86_64.value, "toolchain": "llvm", "llvm-version": "16"},
            {"kernel": "LATEST", "runs_on": [], "arch": Arch.aarch64.value, "toolchain": "gcc", "llvm-version": "17"},
            #{"kernel": "LATEST", "runs_on": [], "arch": Arch.aarch64.value, "toolchain": "llvm", "llvm-version": "17"},
            {"kernel": "LATEST", "runs_on": [], "arch": Arch.s390x.value, "toolchain": "gcc", "llvm-version": "16", "parallel_tests": False},
          ]
          self_hosted_repos = [
            "kernel-patches/bpf",
            "kernel-patches/vmtest",
          ]

          for idx in range(len(matrix) - 1, -1, -1):
            if matrix[idx]['toolchain'] == 'gcc':
              matrix[idx]['toolchain_full'] = 'gcc'
            else:
              matrix[idx]['toolchain_full'] = 'llvm-' + matrix[idx]['llvm-version']
          # Only a few repository within "kernel-patches" use self-hosted runners.
          if "${{ github.repository_owner }}" != "kernel-patches" or "${{ github.repository }}" not in self_hosted_repos:
            # Outside of those repositories, we only run on x86_64 GH hosted runners (ubuntu-latest)
            for idx in range(len(matrix) - 1, -1, -1):
              if matrix[idx]["arch"] != Arch.x86_64.value:
                del matrix[idx]
              else:
                matrix[idx]["runs_on"] = ["ubuntu-latest"]
          else:
            # Otherwise, run on (self-hosted, arch) runners
            for idx in range(len(matrix) - 1, -1, -1):
              matrix[idx]["runs_on"].extend(["self-hosted", matrix[idx]["arch"]])

          build_matrix = {"include": matrix}
          set_output("build_matrix", dumps(build_matrix))

          def get_tests(config):
            tests = [
              "test_progs",
              "test_progs_parallel",
              "test_progs_no_alu32",
              "test_progs_no_alu32_parallel",
              "test_maps",
              "test_verifier",
            ]
            if config.get("parallel_tests", True):
              return tests
            return [test for test in tests if not test.endswith("parallel") ]

          test_matrix = {"include": [{**config, **generate_test_config(test)}
                                      for config in matrix
                                      for test in get_tests(config)
                                    ]}
          set_output("test_matrix", dumps(test_matrix))

          veristat_runs_on = next(x['runs_on']
                                  for x in matrix
                                  if x['arch'] == "${{env.veristat_arch}}" and
                                     x['toolchain'] == "${{env.veristat_toolchain}}")
          set_output("veristat_runs_on", veristat_runs_on)
  build:
    name: build for ${{ matrix.arch }} with ${{ matrix.toolchain_full }}
    needs: set-matrix
    runs-on: ${{ matrix.runs_on }}
    timeout-minutes: 100
    strategy:
      fail-fast: false
      matrix: ${{ fromJSON(needs.set-matrix.outputs.build-matrix) }}
    env:
      KERNEL: ${{ matrix.kernel }}
      REPO_ROOT: ${{ github.workspace }}
      REPO_PATH: ""
      KBUILD_OUTPUT: kbuild-output/
    steps:
      - uses: actions/checkout@v3
        # We fetch an actual bit of history here to facilitate incremental
        # builds (which may check out some earlier upstream change).
        with:
          fetch-depth: 50
      - if: ${{ github.repository == 'kernel-patches/vmtest' }}
        name: Download bpf-next tree
        uses: libbpf/ci/get-linux-source@main
        with:
          dest: '.kernel'
      - if: ${{ github.repository == 'kernel-patches/vmtest' }}
        name: Move linux source in place
        shell: bash
        run: |
          rm -rf .kernel/.git
          cp -rf .kernel/. .
          rm -rf .kernel
      - name: Get commit meta-data
        id: get-commit-metadata
        shell: bash
        run: |
          if [ ${{ github.event_name }} = 'push' ]; then
            branch="${{ github.ref_name }}"
            echo "branch=${branch}" >> "${GITHUB_OUTPUT}"
          else
            branch="${{ github.base_ref }}"
            echo "branch=${branch}" >> "${GITHUB_OUTPUT}"
          fi

          upstream=$(echo "${branch}" | sed 's@_base$@@')
          commit="$(
            git rev-parse "origin/${upstream}" &> /dev/null \
              || (
                git fetch --quiet --prune --no-tags --depth=1 --no-recurse-submodules origin +refs/heads/${upstream}:refs/remotes/origin/${upstream} \
                  && git rev-parse "origin/${upstream}"
              )
          )"

          echo "timestamp=$(TZ=utc git show --format='%cd' --no-patch --date=iso-strict-local ${commit})" >> "${GITHUB_OUTPUT}"
          echo "commit=${commit}" >> "${GITHUB_OUTPUT}"
          echo "Most recent upstream commit is ${commit}"
      - name: Pull recent KBUILD_OUTPUT contents
        uses: actions/cache@v3
        with:
          path: ${{ env.KBUILD_OUTPUT }}
          key: kbuild-output-${{ matrix.arch }}-${{ matrix.toolchain_full }}-${{ steps.get-commit-metadata.outputs.branch }}-${{ steps.get-commit-metadata.outputs.timestamp }}-${{ steps.get-commit-metadata.outputs.commit }}
          restore-keys: |
            kbuild-output-${{ matrix.arch }}-${{ matrix.toolchain_full }}-${{ steps.get-commit-metadata.outputs.branch }}-${{ steps.get-commit-metadata.outputs.timestamp }}-
            kbuild-output-${{ matrix.arch }}-${{ matrix.toolchain_full }}-${{ steps.get-commit-metadata.outputs.branch }}-
            kbuild-output-${{ matrix.arch }}-${{ matrix.toolchain_full }}-
      - name: Prepare incremental build
        shell: bash
        run: |
          set -e -u

          # $1 - the SHA-1 to fetch and check out
          fetch_and_checkout() {
            local build_base_sha="${1}"

            # If cached artifacts became stale for one reason or another, we
            # may not have the build base SHA available. Fetch it and retry.
            git fetch origin "${build_base_sha}" && git checkout --quiet "${build_base_sha}"
          }

          # $1 - value of KBUILD_OUTPUT
          clear_cache_artifacts() {
            local kbuild_output="${1}"
            echo "Unable to find earlier upstream ref. Discarding KBUILD_OUTPUT contents..."
            rm --recursive --force "${kbuild_output}"
            mkdir "${kbuild_output}"
            false
          }

          # $1 - value of KBUILD_OUTPUT
          # $2 - current time in ISO 8601 format
          restore_source_code_times() {
            local kbuild_output="${1}"
            local current_time="${2}"
            local src_time="$(date --iso-8601=ns --date="${current_time} - 2 minutes")"
            local obj_time="$(date --iso-8601=ns --date="${current_time} - 1 minute")"

            git ls-files | xargs --max-args=10000 touch -m --no-create --date="${src_time}"
            find "${kbuild_output}" -type f | xargs --max-args=10000 touch -m --no-create --date="${obj_time}"
            git checkout --quiet -
            echo "Adjusted src and obj time stamps relative to system time"
          }

          mkdir --parents "${KBUILD_OUTPUT}"
          current_time="$(date --iso-8601=ns)"

          if [ -f "${KBUILD_OUTPUT}/.build-base-sha" ]; then
            build_base_sha="$(cat "${KBUILD_OUTPUT}/.build-base-sha")"
            echo "Setting up base build state for ${build_base_sha}"

            (
              git checkout --quiet "${build_base_sha}" \
                || fetch_and_checkout "${build_base_sha}" \
                || clear_cache_artifacts "${KBUILD_OUTPUT}"
            ) && restore_source_code_times "${KBUILD_OUTPUT}" "${current_time}"
          else
            echo "No previous build data found"
          fi

          echo -n "${{ steps.get-commit-metadata.outputs.commit }}" > "${KBUILD_OUTPUT}/.build-base-sha"
      - uses: libbpf/ci/patch-kernel@main
        with:
          patches-root: '${{ github.workspace }}/ci/diffs'
          repo-root: '${{ github.workspace }}'
      - name: Setup build environment
        uses: libbpf/ci/setup-build-env@main
        with:
          llvm-version: ${{ matrix.llvm-version }}
      - name: Build kernel image
        uses: libbpf/ci/build-linux@main
        with:
          arch: ${{ matrix.arch }}
          toolchain: ${{ matrix.toolchain }}
          kbuild-output: ${{ env.KBUILD_OUTPUT }}
          max-make-jobs: 32
          llvm-version: ${{ matrix.llvm-version }}
      - name: Build selftests
        uses: libbpf/ci/build-selftests@main
        with:
          toolchain: ${{ matrix.toolchain }}
          kbuild-output: ${{ env.KBUILD_OUTPUT }}
          max-make-jobs: 32
          llvm-version: ${{ matrix.llvm-version }}
      - if: ${{ github.event_name != 'push' }}
        name: Build samples
        uses: libbpf/ci/build-samples@main
        with:
          toolchain: ${{ matrix.toolchain }}
          kbuild-output: ${{ env.KBUILD_OUTPUT }}
          max-make-jobs: 32
          llvm-version: ${{ matrix.llvm-version }}
      - name: Tar artifacts
        run: |
          # Remove intermediate object files that we have no use for. Ideally
          # we'd just exclude them from tar below, but it does not provide
          # options to express the precise constraints.
          find selftests/ -name "*.o" -a ! -name "*.bpf.o" -print0 | \
            xargs --null --max-args=10000 rm

          # Strip debug information, which is excessively large (consuming
          # bandwidth) while not actually being used (the kernel does not use
          # DWARF to symbolize stacktraces).
          strip --strip-debug "${KBUILD_OUTPUT}"/vmlinux

          file_list=""
          if [ "${{ github.repository }}" == "kernel-patches/vmtest" ]; then
            # Package up a bunch of additional infrastructure to support running
            # 'make kernelrelease' and bpf tool checks later on.
            file_list="$(find . -iname Makefile | xargs) \
              scripts/ \
              tools/testing/selftests/bpf/ \
              tools/include/ \
              tools/bpf/bpftool/";
          fi
          # zstd is installed by default in the runner images.
          tar -cf - \
            "${KBUILD_OUTPUT}"/.config \
            "${KBUILD_OUTPUT}"/$(KBUILD_OUTPUT="${KBUILD_OUTPUT}" make -s image_name) \
            "${KBUILD_OUTPUT}"/include/config/auto.conf \
            "${KBUILD_OUTPUT}"/include/generated/autoconf.h \
            "${KBUILD_OUTPUT}"/vmlinux \
            ${file_list} \
            --exclude '*.cmd' \
            --exclude '*.d' \
            --exclude '*.h' \
            --exclude '*.output' \
            selftests/bpf/ | zstd -T0 -19 -o vmlinux-${{ matrix.arch }}-${{ matrix.toolchain_full }}.tar.zst
      - if: ${{ github.event_name != 'push' }}
        name: Remove KBUILD_OUTPUT contents
        shell: bash
        run: |
          # Remove $KBUILD_OUTPUT to prevent cache creation for pull requests.
          # Only on pushed changes are build artifacts actually cached, because
          # of github.com/actions/cache's cache isolation logic.
          rm -rf "${KBUILD_OUTPUT}"
      - uses: actions/upload-artifact@v3
        with:
          name: vmlinux-${{ matrix.arch }}-${{ matrix.toolchain_full }}
          if-no-files-found: error
          path: vmlinux-${{ matrix.arch }}-${{ matrix.toolchain_full }}.tar.zst
  test:
    if: ${{ github.event_name != 'push' }}
    name: ${{ matrix.test }} on ${{ matrix.arch }} with ${{ matrix.toolchain_full }}
    needs: [set-matrix, build]
    strategy:
      fail-fast: false
      matrix: ${{ fromJSON(needs.set-matrix.outputs.test-matrix) }}
    runs-on: ${{ matrix.runs_on }}
    timeout-minutes: 100
    env:
      KERNEL: ${{ matrix.kernel }}
      REPO_ROOT: ${{ github.workspace }}
      REPO_PATH: ""
      KBUILD_OUTPUT: kbuild-output/
    steps:
      - uses: actions/checkout@v3
      - uses: actions/download-artifact@v3
        with:
          name: vmlinux-${{ matrix.arch }}-${{ matrix.toolchain_full }}
          path: .
      - name: Untar artifacts
        # zstd is installed by default in the runner images.
        run: zstd -d -T0  vmlinux-${{ matrix.arch }}-${{ matrix.toolchain_full }}.tar.zst --stdout | tar -xf -
      - name: Prepare rootfs
        uses: libbpf/ci/prepare-rootfs@main
        with:
          project-name: 'libbpf'
          arch: ${{ matrix.arch }}
          kernel: ${{ matrix.kernel }}
          kernel-root: '.'
          kbuild-output: ${{ env.KBUILD_OUTPUT }}
          image-output: '/tmp/root.img'
          test: ${{ matrix.test }}
      - name: Run selftests
        uses: libbpf/ci/run-qemu@main
        continue-on-error: ${{ matrix.continue_on_error }}
        timeout-minutes: ${{ matrix.timeout_minutes }}
        with:
          arch: ${{ matrix.arch}}
          img: '/tmp/root.img'
          vmlinuz: '${{ github.workspace }}/vmlinuz'
          kernel-root: '.'
          max-cpu: 8
          kernel-test: ${{ matrix.test }}
  veristat:
    name: veristat
    needs: [set-matrix, build]
    runs-on: ${{ fromJSON(needs.set-matrix.outputs.veristat-runs-on) }}
    timeout-minutes: 100
    env:
      KERNEL: LATEST
      REPO_ROOT: ${{ github.workspace }}
      REPO_PATH: ""
      KBUILD_OUTPUT: kbuild-output/
    steps:
      - name: Setup environment variables
        run: |
            echo arch_and_tool=${{ env.veristat_arch }}-${{ env.veristat_toolchain }} > \
              ${GITHUB_ENV}
      - uses: actions/checkout@v3
      - uses: actions/download-artifact@v3
        with:
          name: vmlinux-${{ env.arch_and_tool }}
          path: .
      - name: Untar artifacts
        # zstd is installed by default in the runner images.
        run: zstd -d -T0  vmlinux-${{ env.arch_and_tool }}.tar.zst --stdout | tar -xf -

      - name: Prepare rootfs
        uses: libbpf/ci/prepare-rootfs@main
        with:
          project-name: 'libbpf'
          arch: x86_64
          kernel: LATEST
          kernel-root: '.'
          kbuild-output: ${{ env.KBUILD_OUTPUT }}
          image-output: '/tmp/root.img'
          test: run_veristat

      - name: Run veristat
        uses: libbpf/ci/run-qemu@main
        timeout-minutes: 10
        with:
          arch: x86_64
          img: '/tmp/root.img'
          vmlinuz: '${{ github.workspace }}/vmlinuz'
          kernel-root: '.'
          max-cpu: 8
          kernel-test: run_veristat
          output-dir: '${{ github.workspace }}'

      # veristat.csv is produced by run-qemu run_veristat action
      - uses: actions/upload-artifact@v3
        with:
          name: ${{ env.arch_and_tool }}-veristat-log
          if-no-files-found: error
          path: '${{ github.workspace }}/veristat.csv'

      # For pull request:
      # - get baseline log from cache
      # - compare it to current run
      - if: ${{ github.event_name == 'pull_request' }}
        uses: actions/cache/restore@v3
        with:
          key: ${{ env.arch_and_tool }}-veristat-baseline
          restore-keys: |
            ${{ env.arch_and_tool }}-veristat-baseline-
          path: '${{ github.workspace }}/veristat-baseline.csv'

      - if: ${{ github.event_name == 'pull_request' }}
        name: Show veristat comparison
        run: |
          cd ${{ github.workspace }}
          if [[ ! -f veristat-baseline.csv ]]; then
            echo "No veristat-baseline.csv available"
            echo "# No veristat-baseline.csv available" >> $GITHUB_STEP_SUMMARY
            exit
          fi
          selftests/bpf/veristat \
            --output-format csv \
            --emit file,prog,verdict,states \
            --compare veristat-baseline.csv veristat.csv > compare.csv
          python3 ./.github/scripts/veristat-compare.py compare.csv

      # For push: just put baseline log to cache
      - if: ${{ github.event_name == 'push' }}
        run: |
          mv '${{ github.workspace }}/veristat.csv' \
             '${{ github.workspace }}/veristat-baseline.csv'

      - if: ${{ github.event_name == 'push' }}
        uses: actions/cache/save@v3
        with:
          key: ${{ env.arch_and_tool }}-veristat-baseline-${{ github.run_id }}
          path: '${{ github.workspace }}/veristat-baseline.csv'