build-selftests: change action inputs to those actually required

.github/workflows/kernel-build.yml

@@ -115,17 +115,15 @@ jobs:
           llvm-version: ${{ inputs.llvm-version }}
       - name: Build selftests/bpf
         uses: ./build-selftests
+        env:
+          MAX_MAKE_JOBS: 32
+          RELEASE: ${{ inputs.release && '1' || '' }}
         with:
           arch: ${{ inputs.arch }}
-          toolchain: ${{ inputs.toolchain }}
-          kbuild-output: ${{ env.KBUILD_OUTPUT }}
-          max-make-jobs: 32
+          kernel-root: ${{ env.KERNEL_ROOT }}
           llvm-version: ${{ inputs.llvm-version }}
-        env:
-          # RELEASE= disables all optimizaions
-          # RELEASE=0 adds -O0 make flag
-          # RELEASE=1 adds -O2 make flag
-          RELEASE: ${{ inputs.release && '1' || '' }}
+          toolchain: ${{ inputs.toolchain }}
+
       - if: ${{ env.BUILD_SCHED_EXT_SELFTESTS }}
         name: Build selftests/sched_ext
         uses: ./build-scx-selftests

build-selftests/action.yml

@@ -1,34 +1,27 @@
 name: 'build selftests'
 description: 'Build BPF selftests'
 inputs:
-  kernel:
-    description: 'kernel version'
-    default: 'LATEST'
-  toolchain:
-    description: 'what toolchain to use'
-    default: 'gcc'
-  kbuild-output:
-    description: 'relative or absolute path to use for storing build artifacts'
+  arch:
+    description: 'arch'
+    required: true
+  kernel-root:
+    description: 'Path to the root of the kernel source tree'
     required: true
-  max-make-jobs:
-    description: 'Maximum number of jobs to use when running make (e.g argument to -j). Default: 4*nproc'
-    default: ''
   llvm-version:
     description: 'llvm version'
     required: false
-    default: '16'
-  arch:
-    description: 'arch'
-    required: true
+    default: '18'
+  toolchain:
+    description: 'gcc or llvm'
+    default: 'gcc'
 
 runs:
   using: "composite"
   steps:
     - name: build selftests
       shell: bash
-      run: |
-        kbuild_output="$(realpath ${{ inputs.kbuild-output }})"
-        export LLVM_VERSION=${{ inputs.llvm-version }}
-        ${GITHUB_ACTION_PATH}/build_selftests.sh "${{ inputs.arch }}" "${{ inputs.kernel }}" "${{ inputs.toolchain }}" "${kbuild_output}"
       env:
-        MAX_MAKE_JOBS: ${{ inputs.max-make-jobs }}
+        LLVM_VERSION: ${{ inputs.llvm-version }}
+      run: |
+        ${GITHUB_ACTION_PATH}/build_selftests.sh "${{ inputs.arch }}" "${{ inputs.toolchain }}" "${{ inputs.kernel-root }}"
+

build-selftests/build_selftests.sh

@@ -5,10 +5,12 @@ set -euo pipefail
 source "${GITHUB_ACTION_PATH}/../helpers.sh"
 
 TARGET_ARCH="$1"
-KERNEL="$2"
-TOOLCHAIN="$3"
-export KBUILD_OUTPUT="$4"
-VMLINUX_H=${VMLINUX_H:-}
+TOOLCHAIN="$2"
+KERNEL_ROOT="$(realpath $3)"
+
+export KBUILD_OUTPUT="${KBUILD_OUTPUT:-${KERNEL_ROOT}}"
+export VMLINUX_BTF="${VMLINUX_BTF:-${KBUILD_OUTPUT}/vmlinux}"
+export VMLINUX_H="${VMLINUX_H:-}"
 
 ARCH="$(platform_to_kernel_arch ${TARGET_ARCH})"
 CROSS_COMPILE=""
@@ -25,11 +27,6 @@ fi
 
 foldable start build_selftests "Building selftests with $TOOLCHAIN"
 
-PREPARE_SELFTESTS_SCRIPT=$(find $GITHUB_WORKSPACE -name prepare_selftests-${KERNEL}.sh)
-if [ -f "${PREPARE_SELFTESTS_SCRIPT}" ]; then
-	(cd "${KERNEL_ROOT}/tools/testing/selftests/bpf" && ${PREPARE_SELFTESTS_SCRIPT})
-fi
-
 MAKE_OPTS=$(cat <<EOF
 	ARCH=${ARCH}
 	CROSS_COMPILE=${CROSS_COMPILE}