Merge "SOONG: BPF: add libbpf_prog soong module" into main

android/androidmk.go

@@ -913,6 +913,7 @@ func translateAndroidModule(ctx SingletonContext, w io.Writer, moduleInfoJSONs *
 		case "*android_sdk.sdkRepoHost": // doesn't go through base_rules
 		case "*apex.apexBundle": // license properties written
 		case "*bpf.bpf": // license properties written (both for module and objs)
+		case "*libbpf_prog.libbpfProg": // license properties written (both for module and objs)
 		case "*genrule.Module": // writes non-custom before adding .phony
 		case "*java.SystemModules": // doesn't go through base_rules
 		case "*java.systemModulesImport": // doesn't go through base_rules

bpf/libbpf/Android.bp

@@ -0,0 +1,38 @@
+//
+// Copyright (C) 2024 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+bootstrap_go_package {
+    name: "soong-libbpf",
+    pkgPath: "android/soong/bpf/libbpf",
+    deps: [
+        "blueprint",
+        "blueprint-proptools",
+        "soong-android",
+        "soong-cc",
+        "soong-cc-config",
+    ],
+    srcs: [
+        "libbpf_prog.go",
+    ],
+    testSrcs: [
+        "libbpf_prog_test.go",
+    ],
+    pluginFor: ["soong_build"],
+}

bpf/libbpf/libbpf_prog.go

@@ -0,0 +1,278 @@
+// Copyright (C) 2024 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package libbpf_prog
+
+import (
+	"fmt"
+	"io"
+	"runtime"
+	"strings"
+
+	"android/soong/android"
+	"android/soong/cc"
+	"android/soong/genrule"
+
+	"github.com/google/blueprint"
+)
+
+type libbpfProgDepType struct {
+	blueprint.BaseDependencyTag
+}
+
+func init() {
+	registerLibbpfProgBuildComponents(android.InitRegistrationContext)
+	pctx.Import("android/soong/cc/config")
+	pctx.StaticVariable("relPwd", cc.PwdPrefix())
+}
+
+var (
+	pctx = android.NewPackageContext("android/soong/bpf/libbpf_prog")
+
+	libbpfProgCcRule = pctx.AndroidStaticRule("libbpfProgCcRule",
+		blueprint.RuleParams{
+			Depfile:     "${out}.d",
+			Deps:        blueprint.DepsGCC,
+			Command:     "$relPwd $ccCmd --target=bpf -c $cFlags -MD -MF ${out}.d -o $out $in",
+			CommandDeps: []string{"$ccCmd"},
+		},
+		"ccCmd", "cFlags")
+
+	libbpfProgStripRule = pctx.AndroidStaticRule("libbpfProgStripRule",
+		blueprint.RuleParams{
+			Command: `$stripCmd --strip-unneeded --remove-section=.rel.BTF ` +
+				`--remove-section=.rel.BTF.ext --remove-section=.BTF.ext $in -o $out`,
+			CommandDeps: []string{"$stripCmd"},
+		},
+		"stripCmd")
+
+	libbpfProgDepTag = libbpfProgDepType{}
+)
+
+func registerLibbpfProgBuildComponents(ctx android.RegistrationContext) {
+	ctx.RegisterModuleType("libbpf_prog", LibbpfProgFactory)
+}
+
+var PrepareForTestWithLibbpfProg = android.GroupFixturePreparers(
+	android.FixtureRegisterWithContext(registerLibbpfProgBuildComponents),
+	android.FixtureAddFile("libbpf_headers/Foo.h", nil),
+	android.FixtureAddFile("libbpf_headers/Android.bp", []byte(`
+		genrule {
+			name: "libbpf_headers",
+			out: ["foo.h",],
+		}
+	`)),
+	genrule.PrepareForTestWithGenRuleBuildComponents,
+)
+
+type LibbpfProgProperties struct {
+	// source paths to the files.
+	Srcs []string `android:"path"`
+
+	// additional cflags that should be used to build the libbpf variant of
+	// the C/C++ module.
+	Cflags []string `android:"arch_variant"`
+
+	// list of directories relative to the Blueprint file that will
+	// be added to the include path using -I
+	Local_include_dirs []string `android:"arch_variant"`
+
+	// optional subdirectory under which this module is installed into.
+	Relative_install_path string
+}
+
+type libbpfProg struct {
+	android.ModuleBase
+	properties LibbpfProgProperties
+	objs android.Paths
+}
+
+var _ android.ImageInterface = (*libbpfProg)(nil)
+
+func (libbpf *libbpfProg) ImageMutatorBegin(ctx android.BaseModuleContext) {}
+
+func (libbpf *libbpfProg) VendorVariantNeeded(ctx android.BaseModuleContext) bool {
+	return false
+}
+
+func (libbpf *libbpfProg) ProductVariantNeeded(ctx android.BaseModuleContext) bool {
+	return false
+}
+
+func (libbpf *libbpfProg) CoreVariantNeeded(ctx android.BaseModuleContext) bool {
+	return true
+}
+
+func (libbpf *libbpfProg) RamdiskVariantNeeded(ctx android.BaseModuleContext) bool {
+	return false
+}
+
+func (libbpf *libbpfProg) VendorRamdiskVariantNeeded(ctx android.BaseModuleContext) bool {
+	return false
+}
+
+func (libbpf *libbpfProg) DebugRamdiskVariantNeeded(ctx android.BaseModuleContext) bool {
+	return false
+}
+
+func (libbpf *libbpfProg) RecoveryVariantNeeded(ctx android.BaseModuleContext) bool {
+	return false
+}
+
+func (libbpf *libbpfProg) ExtraImageVariations(ctx android.BaseModuleContext) []string {
+	return nil
+}
+
+func (libbpf *libbpfProg) SetImageVariation(ctx android.BaseModuleContext, variation string) {
+}
+
+func (libbpf *libbpfProg) DepsMutator(ctx android.BottomUpMutatorContext) {
+	ctx.AddDependency(ctx.Module(), libbpfProgDepTag, "libbpf_headers")
+}
+
+func (libbpf *libbpfProg) GenerateAndroidBuildActions(ctx android.ModuleContext) {
+	var cFlagsDeps android.Paths
+	cflags := []string{
+		"-nostdlibinc",
+
+		// Make paths in deps files relative
+		"-no-canonical-prefixes",
+
+		"-O2",
+		"-Wall",
+		"-Werror",
+		"-Wextra",
+
+		"-isystem bionic/libc/include",
+		"-isystem bionic/libc/kernel/uapi",
+		// The architecture doesn't matter here, but asm/types.h is included by linux/types.h.
+		"-isystem bionic/libc/kernel/uapi/asm-arm64",
+		"-isystem bionic/libc/kernel/android/uapi",
+		"-I " + ctx.ModuleDir(),
+		"-g", //Libbpf builds require BTF data
+	}
+
+	if runtime.GOOS != "darwin" {
+		cflags = append(cflags, "-fdebug-prefix-map=/proc/self/cwd=")
+	}
+
+	ctx.VisitDirectDeps(func(dep android.Module) {
+		depTag := ctx.OtherModuleDependencyTag(dep)
+		if depTag == libbpfProgDepTag {
+			if genRule, ok := dep.(genrule.SourceFileGenerator); ok {
+				cFlagsDeps = append(cFlagsDeps, genRule.GeneratedDeps()...)
+				dirs := genRule.GeneratedHeaderDirs()
+				for _, dir := range dirs {
+					cflags = append(cflags, "-I "+dir.String())
+				}
+			} else {
+				depName := ctx.OtherModuleName(dep)
+				ctx.ModuleErrorf("module %q is not a genrule", depName)
+			}
+		}
+	})
+
+	for _, dir := range android.PathsForModuleSrc(ctx, libbpf.properties.Local_include_dirs) {
+		cflags = append(cflags, "-I "+dir.String())
+	}
+
+	cflags = append(cflags, libbpf.properties.Cflags...)
+
+	srcs := android.PathsForModuleSrc(ctx, libbpf.properties.Srcs)
+
+	for _, src := range srcs {
+		if strings.ContainsRune(src.Base(), '_') {
+			ctx.ModuleErrorf("invalid character '_' in source name")
+		}
+		obj := android.ObjPathWithExt(ctx, "unstripped", src, "o")
+
+		ctx.Build(pctx, android.BuildParams{
+			Rule:      libbpfProgCcRule,
+			Input:     src,
+			Implicits: cFlagsDeps,
+			Output:    obj,
+			Args: map[string]string{
+				"cFlags": strings.Join(cflags, " "),
+				"ccCmd":  "${config.ClangBin}/clang",
+			},
+		})
+
+		objStripped := android.ObjPathWithExt(ctx, "", src, "o")
+		ctx.Build(pctx, android.BuildParams{
+			Rule:   libbpfProgStripRule,
+			Input:  obj,
+			Output: objStripped,
+			Args: map[string]string{
+				"stripCmd": "${config.ClangBin}/llvm-strip",
+			},
+		})
+		libbpf.objs = append(libbpf.objs, objStripped.WithoutRel())
+	}
+
+	installDir := android.PathForModuleInstall(ctx, "etc", "bpf/libbpf")
+	if len(libbpf.properties.Relative_install_path) > 0 {
+		installDir = installDir.Join(ctx, libbpf.properties.Relative_install_path)
+	}
+	for _, obj := range libbpf.objs {
+		ctx.PackageFile(installDir, obj.Base(), obj)
+	}
+
+	android.SetProvider(ctx, blueprint.SrcsFileProviderKey, blueprint.SrcsFileProviderData{SrcPaths: srcs.Strings()})
+
+	ctx.SetOutputFiles(libbpf.objs, "")
+}
+
+func (libbpf *libbpfProg) AndroidMk() android.AndroidMkData {
+	return android.AndroidMkData{
+		Custom: func(w io.Writer, name, prefix, moduleDir string, data android.AndroidMkData) {
+			var names []string
+			fmt.Fprintln(w)
+			fmt.Fprintln(w, "LOCAL_PATH :=", moduleDir)
+			fmt.Fprintln(w)
+			var localModulePath string
+			localModulePath = "LOCAL_MODULE_PATH := $(TARGET_OUT_ETC)/bpf/libbpf"
+			if len(libbpf.properties.Relative_install_path) > 0 {
+				localModulePath += "/" + libbpf.properties.Relative_install_path
+			}
+			for _, obj := range libbpf.objs {
+				objName := name + "_" + obj.Base()
+				names = append(names, objName)
+				fmt.Fprintln(w, "include $(CLEAR_VARS)", " # libbpf.libbpf.obj")
+				fmt.Fprintln(w, "LOCAL_MODULE := ", objName)
+				fmt.Fprintln(w, "LOCAL_PREBUILT_MODULE_FILE :=", obj.String())
+				fmt.Fprintln(w, "LOCAL_MODULE_STEM :=", obj.Base())
+				fmt.Fprintln(w, "LOCAL_MODULE_CLASS := ETC")
+				fmt.Fprintln(w, localModulePath)
+				// AconfigUpdateAndroidMkData may have added elements to Extra.  Process them here.
+				for _, extra := range data.Extra {
+					extra(w, nil)
+				}
+				fmt.Fprintln(w, "include $(BUILD_PREBUILT)")
+				fmt.Fprintln(w)
+			}
+			fmt.Fprintln(w, "include $(CLEAR_VARS)", " # libbpf.libbpf")
+			fmt.Fprintln(w, "LOCAL_MODULE := ", name)
+			android.AndroidMkEmitAssignList(w, "LOCAL_REQUIRED_MODULES", names)
+			fmt.Fprintln(w, "include $(BUILD_PHONY_PACKAGE)")
+		},
+	}
+}
+
+func LibbpfProgFactory() android.Module {
+	module := &libbpfProg{}
+
+	module.AddProperties(&module.properties)
+	android.InitAndroidArchModule(module, android.DeviceSupported, android.MultilibFirst)
+	return module
+}

bpf/libbpf/libbpf_prog_test.go

@@ -0,0 +1,69 @@
+// Copyright 2024 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package libbpf_prog
+
+import (
+	"os"
+	"testing"
+
+	"android/soong/android"
+	"android/soong/cc"
+)
+
+func TestMain(m *testing.M) {
+	os.Exit(m.Run())
+}
+
+var prepareForLibbpfProgTest = android.GroupFixturePreparers(
+	cc.PrepareForTestWithCcDefaultModules,
+	android.FixtureMergeMockFs(
+		map[string][]byte{
+			"bpf.c":              nil,
+			"bpf_invalid_name.c": nil,
+			"BpfTest.cpp":        nil,
+		},
+	),
+	PrepareForTestWithLibbpfProg,
+)
+
+func TestLibbpfProgDataDependency(t *testing.T) {
+	bp := `
+		libbpf_prog {
+			name: "bpf.o",
+			srcs: ["bpf.c"],
+		}
+
+		cc_test {
+			name: "vts_test_binary_bpf_module",
+			srcs: ["BpfTest.cpp"],
+			data: [":bpf.o"],
+			gtest: false,
+		}
+	`
+
+	prepareForLibbpfProgTest.RunTestWithBp(t, bp)
+}
+
+func TestLibbpfProgSourceName(t *testing.T) {
+	bp := `
+		libbpf_prog {
+			name: "bpf_invalid_name.o",
+			srcs: ["bpf_invalid_name.c"],
+		}
+	`
+	prepareForLibbpfProgTest.ExtendWithErrorHandler(android.FixtureExpectsOneErrorPattern(
+		`invalid character '_' in source name`)).
+		RunTestWithBp(t, bp)
+}