Move to 22

.github/workflows/ci.yml

@@ -17,10 +17,10 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Setup Java 21
+      - name: Setup Java 22
         uses: actions/setup-java@v4
         with:
-          java-version: '21'
+          java-version: '22'
           distribution: 'adopt'
 
       - name: Cache Maven
@@ -58,7 +58,7 @@ jobs:
       - name: Set up Java
         uses: actions/setup-java@v4
         with:
-          java-version: '21'
+          java-version: '22'
           distribution: 'adopt'
 
       - run: sudo pip3 install https://github.com/amluto/virtme/archive/beb85146cd91de37ae455eccb6ab67c393e6e290.zip

.github/workflows/early-access.yml

@@ -5,7 +5,7 @@ on:
     branches: [ main ]
 
 env:
-  JAVA_VERSION: '21'
+  JAVA_VERSION: '22'
   JAVA_DISTRO: 'adopt'
 
 jobs:

.github/workflows/release.yml

@@ -8,7 +8,7 @@ on:
         required: true
 
 env:
-  JAVA_VERSION: '21'
+  JAVA_VERSION: '22'
   JAVA_DISTRO: 'adopt'
 
 jobs:

.gitignore

@@ -403,4 +403,5 @@ hello-ebpf.iml
 *.zst
 *.c
 kprobe*
-vmlinux*
+vmlinux*
+**/jextract-*

README.md

@@ -56,19 +56,19 @@ These might change in the future, but for now, you need the following:
 Either a Linux machine with the following:
 
 - Linux 64-bit (or a VM)
-- Java 21 (exactly this version, as we need [Project Panama](https://openjdk.org/projects/panama/) with is a preview
-  feature), we'll switch to Java 22 as soon as it is released
+- Java 22 or later
 - libbcc (see [bcc installation instructions](https://github.com/iovisor/bcc/blob/master/INSTALL.md), be sure to install the libbpfcc-dev package)
   - e.g. `apt install bpfcc-tools libbpfcc-dev linux-tools-common linux-tools-$(uname -r)` on Ubuntu
 - root privileges (for eBPF programs)
 On Mac OS, you can use the [Lima VM](https://lima-vm.io/) (or use the `hello-ebpf.yaml` file as a guide to install the prerequisites):
 
 ```sh
-limactl start hello-ebpf.yaml
+limactl start hello-ebpf.yaml --mount-writable
+limactl shell hello-ebpf sudo bin/install.sh
 limactl shell hello-ebpf
 
 # You'll need to be root for most of the examples
-sudo -s
+sudo -s PATH=$PATH
 ```
 
 Build
@@ -81,10 +81,10 @@ To build the project, make sure you have all prerequisites installed, then just
 
 Running the examples
 --------------------
-Be sure to run the following in a shell with root privileges that uses JDK 21:
+Be sure to run the following in a shell with root privileges that uses JDK 22:
 
 ```shell
-java --enable-preview -cp bcc/target/bcc.jar --enable-native-access=ALL-UNNAMED me.bechberger.ebpf.samples.EXAMPLE_NAME
+java -cp bcc/target/bcc.jar --enable-native-access=ALL-UNNAMED me.bechberger.ebpf.samples.EXAMPLE_NAME
 # or in the project directory
 ./run.sh EXAMPLE_NAME
 
@@ -225,6 +225,7 @@ You can run them using the `./run_bpf.sh` script. All examples have accompanying
 | Ansil H | [RingSample](bpf/src/main/java/me/bechberger/ebpf/samples/RingSample.java)                     | Record openat calls in a ring buffer  |
 |         | [TypeProcessingSample](bpf/src/main/java/me/bechberger/ebpf/samples/TypeProcessingSample.java) | RingSample using the @Type annotation |
 |         | [HashMapSample](bpf/src/main/java/me/bechberger/ebpf/samples/HashMapSample.java)               | Record openat calls in a hash map     |
+|         | [TypeProcessingSample](bpf/src/main/java/me/bechberger/ebpf/samples/TypeProcessingSample.java) | RingSample using more code generation |
 
 Classes and Methods
 -------

annotations/pom.xml

@@ -13,8 +13,8 @@
     <artifactId>ebpf-annotations</artifactId>
 
     <properties>
-        <maven.compiler.source>21</maven.compiler.source>
-        <maven.compiler.target>21</maven.compiler.target>
+        <maven.compiler.source>22</maven.compiler.source>
+        <maven.compiler.target>22</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
 

annotations/src/main/java/me/bechberger/ebpf/annotations/bpf/BPF.java

@@ -21,4 +21,9 @@
  */
 @Target(ElementType.TYPE)
 public @interface BPF {
+    /**
+     * License of the eBPF program, the EBPF_PROGRAM contains a <code>SEC("license")</code> variable
+     * only iff this license is not present. Typically, the license is GPL.
+     */
+    String license() default "";
 }

annotations/src/main/java/me/bechberger/ebpf/annotations/bpf/BPFMapClass.java

@@ -0,0 +1,51 @@
+package me.bechberger.ebpf.annotations.bpf;
+
+import java.io.FileDescriptor;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Specify that a class is a BPF map class
+ */
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.CLASS)
+public @interface BPFMapClass {
+    /**
+     * Template for the generated C code
+     * <p>
+     * Available placeholders:
+     * <ul>
+     *     <li>$field: The field name</li>
+     *     <li>$maxEntries: max entries as specified in the {@link BPFMapDefinition} annotation</li>
+     *     <li>$class: name of the class</li>
+     *     <li>$c1, ...: C type names for every generic type parameter</li>
+     *     <li>$b1, ...: BPFTypes</li>
+     *     <li>$j1, ...: Java class names</li>
+     * </ul>
+     * <p>
+     * Example:
+     * {@snippet :
+     *  struct {
+     *     __uint (type, BPF_MAP_TYPE_RINGBUF);
+     *     __uint (max_entries, $maxEntries);
+     *  } $field SEC(".maps");
+     * }
+     */
+    String cTemplate();
+
+    /**
+     * Code template for generating the Java generation code, see {@link BPFMapClass#cTemplate()} for available placeholders,
+     * here are the additions:
+     * <ul>
+     *     <li>$fd: code that creates a FileDescriptor instance</li>
+     * </ul>
+     * <p>
+     * Example:
+     * {@snippet :
+     * new $class<>($fd, $b1)
+     * }
+     */
+    String javaTemplate();
+}

annotations/src/main/java/me/bechberger/ebpf/annotations/bpf/BPFMapDefinition.java

@@ -0,0 +1,30 @@
+package me.bechberger.ebpf.annotations.bpf;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Declare maps for the eBPF program by annotating non-final, non-private instance fields of a type
+ * annotated with {@link BPFMapClass} with this annotation. The generic type parameters have to adhere
+ * to the same constraints as the members of {@link Type} annotated records.
+ * <p>
+ * Example:
+ * {@snippet :
+ *   @BPFMapDefinition(maxEntries = 1024)
+ *   private BPFHashMap<Integer, Integer> map;
+ * }
+ * this defines a hash map with 1024 entries.
+ */
+@Target(ElementType.TYPE_USE)
+@Retention(RetentionPolicy.CLASS)
+public @interface BPFMapDefinition {
+    /**
+     * Maximum number of entries in the map.
+     * <p>
+     * For ring buffers, this is the number of bytes in the buffer which should be a multiple of the kernel page size
+     * (usually 4096), has to be larger than zero
+     */
+    int maxEntries();
+}

annotations/src/main/java/me/bechberger/ebpf/annotations/bpf/Type.java

@@ -23,7 +23,6 @@
  *     <li>integer types (int, long, ...), optionally annotated with {@link Unsigned} if unsigned</li>
  *     <li>String types, annotated with {@link Size} to specify the size</li>
  *     <li>Other {@link Type} annotated types</li>
- *     <li>{@link Type.Member} annotated member, to specify the BPFType directly</li>
  * </ul>
  */
 @Target(ElementType.TYPE)
@@ -32,11 +31,6 @@
     /** Name of the generated BPFStructType, uses the type as default */
     String name() default "";
 
-    @Target({ElementType.TYPE, ElementType.TYPE_USE})
-    @Retention(RetentionPolicy.CLASS)
-    public @interface Member {
-
-        /** Java statement directly copied into the result at the place of the BPFType */
-        String bpfType();
-    }
-}
+    /** Don't generate C code and insert it into the ebpf program string */
+    boolean noCCodeGeneration() default false;
+}

bcc/pom.xml

@@ -38,8 +38,8 @@
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <maven.compiler.source>21</maven.compiler.source>
-        <maven.compiler.target>21</maven.compiler.target>
+        <maven.compiler.source>22</maven.compiler.source>
+        <maven.compiler.target>22</maven.compiler.target>
     </properties>
 
     <build>
@@ -50,7 +50,8 @@
                 <artifactId>maven-compiler-plugin</artifactId>
                 <version>3.8.1</version>
                 <configuration>
-                    <compilerArgs>--enable-preview</compilerArgs>
+                    <source>22</source>
+                    <target>22</target>
                 </configuration>
             </plugin>
             <plugin>
@@ -85,7 +86,7 @@
         <dependency>
             <groupId>me.bechberger</groupId>
             <artifactId>rawbcc</artifactId>
-            <version>0.1.3</version>
+            <version>0.1.4</version>
         </dependency>
         <dependency>
             <groupId>me.bechberger</groupId>
@@ -111,4 +112,4 @@
         <artifactId>hello-ebpf</artifactId>
         <version>0.1.0-SNAPSHOT</version>
     </parent>
-</project>
+</project>