SapMachine #2023: Add suport for SAP JMC agent

Author: schmelter-sap

make/TestImage.gmk

@@ -46,6 +46,14 @@ $(README):
 
 TARGETS += $(BUILD_INFO_PROPERTIES) $(README)
 
+# SapMachine 2025-08-11: Copy test jar for SAP JMC agent if needed.
+ifeq ($(SAP_JMC_AGENT_ENABLED), true)
+  $(TEST_IMAGE_DIR)/jars/agent-tests.jar: $(SAP_JMC_AGENT_PATH)/agent-$(SAP_JMC_AGENT_VERSION)-tests.jar
+	$(call install-file)
+
+  TARGETS += $(TEST_IMAGE_DIR)/jars/agent-tests.jar
+endif
+
 ################################################################################
 
 prepare-test-image: $(TARGETS)

make/autoconf/configure.ac

@@ -215,6 +215,9 @@ JDKOPT_SETUP_CODE_COVERAGE
 # AddressSanitizer
 JDKOPT_SETUP_ADDRESS_SANITIZER
 
+# SapMachine 2024-12-05: Setup SAP JMC agent if requested
+JDKOPT_SETUP_SAP_JMC_AGENT
+
 ###############################################################################
 #
 # Check dependencies for external and internal libraries.

make/autoconf/jdk-options.m4

@@ -373,6 +373,30 @@ AC_DEFUN_ONCE([JDKOPT_SETUP_DEBUG_SYMBOLS],
   AC_SUBST(SHIP_DEBUG_SYMBOLS)
 ])
 
+################################################################################
+# SapMachine 2025-08-11: import JMC agent jars
+AC_DEFUN_ONCE([JDKOPT_SETUP_SAP_JMC_AGENT],
+[
+  AC_ARG_WITH(sap-jmc-agent, [AS_HELP_STRING([--with-sap-jmc-agent],
+      [Set import path for the SAP JMC agent jars])])
+  SAP_JMC_AGENT_ENABLED=false
+  if test "x$with_sap_jmc_agent" != x; then
+    SAP_JMC_AGENT_PATH="$with_sap_jmc_agent"
+	UTIL_FIXUP_PATH(SAP_JMC_AGENT_PATH)
+    if test -f "$SAP_JMC_AGENT_PATH"/agent-*-boot.jar; then
+      SAP_JMC_AGENT_VERSION=$($BASENAME "$SAP_JMC_AGENT_PATH"/agent-*-boot.jar | $SED -e 's/^agent-//' -e 's/-boot.jar$//')
+      SAP_JMC_AGENT_ENABLED=true
+      JVM_CFLAGS="$JVM_CFLAGS -DWITH_SAP_JMC_AGENT=1"
+      AC_MSG_NOTICE([SAP JMC agent found at $SAP_JMC_AGENT_PATH, version $SAP_JMC_AGENT_VERSION])
+    else
+      AC_MSG_ERROR([SAP JMC agent was set, but the agent jars were not found])
+    fi
+  fi
+  AC_SUBST(SAP_JMC_AGENT_PATH)
+  AC_SUBST(SAP_JMC_AGENT_VERSION)
+  AC_SUBST(SAP_JMC_AGENT_ENABLED)
+])
+
 ################################################################################
 #
 # Native and Java code coverage

make/autoconf/spec.gmk.in

@@ -422,6 +422,11 @@ UNLIMITED_CRYPTO=@UNLIMITED_CRYPTO@
 ASYNC_PROFILER_IMPORT_PATH=@ASYNC_PROFILER_IMPORT_PATH@
 ASYNC_PROFILER_IMPORT_ENABLED=@ASYNC_PROFILER_IMPORT_ENABLED@
 
+# SapMachine 2025-08-11: import SAP JMC agent jars
+SAP_JMC_AGENT_PATH=@SAP_JMC_AGENT_PATH@
+SAP_JMC_AGENT_VERSION=@SAP_JMC_AGENT_VERSION@
+SAP_JMC_AGENT_ENABLED=@SAP_JMC_AGENT_ENABLED@
+
 GCOV_ENABLED=@GCOV_ENABLED@
 JCOV_ENABLED=@JCOV_ENABLED@
 JCOV_HOME=@JCOV_HOME@

make/modules/java.base/Copy.gmk

@@ -279,3 +279,14 @@ ifeq ($(call isTargetOs, linux macosx), true)
 endif
 
 ################################################################################
+# SapMachine 2025-08-11: Copy jmc agent jars
+ifeq ($(SAP_JMC_AGENT_ENABLED), true)
+  $(LIB_DST_DIR)/agent.jar: $(SAP_JMC_AGENT_PATH)/agent-$(SAP_JMC_AGENT_VERSION).jar
+	$(call install-file)
+  $(LIB_DST_DIR)/agent-boot.jar: $(SAP_JMC_AGENT_PATH)/agent-$(SAP_JMC_AGENT_VERSION)-boot.jar
+	$(call install-file)
+
+  TARGETS += $(LIB_DST_DIR)/agent.jar $(LIB_DST_DIR)/agent-boot.jar
+endif
+
+################################################################################

src/hotspot/share/runtime/arguments.cpp

@@ -2478,6 +2478,29 @@ jint Arguments::parse_each_vm_init_arg(const JavaVMInitArgs* args, bool* patch_m
         }
       }
 #endif // !INCLUDE_JVMTI
+    // SapMachine 2025-08-11: Handle jmc agent if requested.
+    } else if (match_option(option, "-jmcagent:", &tail)) {
+#if !defined(WITH_SAP_JMC_AGENT)
+      jio_fprintf(defaultStream::error_stream(),
+          "SAP JMC agent is not included in this VM\n");
+      return JNI_ERR;
+#else
+#if !INCLUDE_JVMTI
+#error "Must have JVMTI enabled with SAP JMC agent"
+#endif
+      char const* agent_jar = "agent.jar";
+      if (tail != nullptr) {
+        size_t length = strlen(tail) + strlen(_java_home->value()) + strlen(agent_jar) + 7;
+        char* options = NEW_C_HEAP_ARRAY(char, length, mtArguments);
+        jio_snprintf(options, length, "%s/lib/%s=%s", _java_home->value(), agent_jar, tail);
+        add_instrument_agent("instrument", options, false);
+
+        // java agents need module java.instrument
+        if (!create_numbered_module_property("jdk.module.addmods", "java.instrument", addmods_count++)) {
+          return JNI_ENOMEM;
+        }
+      }
+#endif // !WITH_SAP_JMC_AGENT
     // --enable_preview
     } else if (match_option(option, "--enable-preview")) {
       set_enable_preview();

src/hotspot/share/services/diagnosticCommand.cpp

@@ -122,6 +122,10 @@ void DCmdRegistrant::register_dcmds(){
 #endif // INCLUDE_SERVICES
 #if INCLUDE_JVMTI
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<JVMTIDataDumpDCmd>(full_export, true, false));
+  // SapMachine 2025-08-11: Add support for SAP JMC agent if requested.
+#if defined(WITH_SAP_JMC_AGENT)
+  DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<JVMTIJmcAgentLoadDCmd>(full_export, true, false));
+#endif // WITH_SAP_JMC_AGENT
 #endif // INCLUDE_JVMTI
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<ThreadDumpDCmd>(full_export, true, false));
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<ClassLoaderStatsDCmd>(full_export, true, false));
@@ -354,6 +358,36 @@ void JVMTIAgentLoadDCmd::execute(DCmdSource source, TRAPS) {
   }
 }
 
+// SapMachine 2025-08-11
+#if defined(WITH_SAP_JMC_AGENT)
+JVMTIJmcAgentLoadDCmd::JVMTIJmcAgentLoadDCmd(outputStream* output, bool heap) :
+  DCmdWithParser(output, heap),
+  _option("agent option", "Option string to pass the JMC agent.", "STRING", false) {
+  _dcmdparser.add_dcmd_argument(&_option);
+}
+
+void JVMTIJmcAgentLoadDCmd::execute(DCmdSource source, TRAPS) {
+  char const* java_home = Arguments::get_java_home();
+  char const* agent_jar = "agent.jar";
+  char const* option = _option.value();
+  size_t len = strlen(java_home) + strlen(agent_jar) + (option == nullptr ? 0 : 1 + strlen(option)) + 7;
+  char* agent_line = (char*)os::malloc(len, mtInternal);
+
+  if (agent_line == nullptr) {
+    output()->print_cr("JVMTI JMC agent attach failed: "
+      "Could not allocate " SIZE_FORMAT " bytes for argument.",
+      len);
+     return;
+  }
+
+  jio_snprintf(agent_line, len, "%s/lib/%s%s%s", java_home, agent_jar, option == nullptr ? "" : "=",
+    option == nullptr ? "" : option);
+  JvmtiExport::load_agent_library("instrument", "false", agent_line, output());
+
+  os::free(agent_line);
+}
+#endif // WITH_SAP_JMC_AGENT
+
 #endif // INCLUDE_JVMTI
 #endif // INCLUDE_SERVICES
 

src/hotspot/share/services/diagnosticCommand.hpp

@@ -189,6 +189,31 @@ class JVMTIAgentLoadDCmd : public DCmdWithParser {
   }
   virtual void execute(DCmdSource source, TRAPS);
 };
+
+// SapMachine 2025-08-11
+#if defined(WITH_SAP_JMC_AGENT)
+class JVMTIJmcAgentLoadDCmd : public DCmdWithParser {
+protected:
+    DCmdArgument<char*> _option;
+public:
+    JVMTIJmcAgentLoadDCmd(outputStream* output, bool heap);
+    static int num_arguments() { return 1; }
+    static const char* name() { return "JVMTI.jmc_agent_load"; }
+    static const char* description() {
+        return "Load the SAP jmc agent.";
+    }
+    static const char* impact() {
+        return "Medium: Depends on the command or trace";
+    }
+    static const JavaPermission permission() {
+        JavaPermission p = { "java.lang.management.ManagementPermission",
+                            "control", nullptr };
+        return p;
+    }
+    virtual void execute(DCmdSource source, TRAPS);
+};
+#endif // WITH_SAP_JMC_AGENT
+
 #endif // INCLUDE_JVMTI
 #endif // INCLUDE_SERVICES
 

test/jdk/TEST.groups

@@ -63,6 +63,7 @@ tier1_sapmachine = \
     java/net/Socket/ExceptionText.java \
     java/util/jar/Manifest/IncludeInExceptionsTest.java \
     jdk/security/JavaDotSecurity/TestJDKIncludeInExceptions.java \
+    sap \
     sun/security/lib/cacerts/VerifyCACerts.java \
     tools/jlink/plugins/AddSapMachineToolsTest.java \
     tools/launcher/HelpFlagsTest.java \

test/jdk/sap/JmcAgentIntegrationTest.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2025 SAP SE. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+/**
+ * @test
+ * @summary Runs the test for the jmc agent integration.
+ *
+ * @run main/othervm JmcAgentIntegrationTest
+ */
+
+import java.lang.reflect.Method;
+import java.io.File;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.nio.file.DirectoryStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+
+public class JmcAgentIntegrationTest {
+
+    public static void main(String[] args) throws Exception {
+        File jar = new File(System.getenv("TEST_IMAGE_DIR") + "/jars/agent-tests.jar");
+
+        if (!jar.exists()) {
+            return; // Feature was not enabled.
+        }
+
+        ArrayList<String> testOptions = new ArrayList<>();
+        testOptions.add("-dump");
+
+        // Only run VM-agnostic tests if the ASM version we are using cannot handle the class file spec of this VM.
+        int spec = Integer.getInteger("java.vm.specification.version", 99999);
+        String javaHome = System.getProperty("java.home");
+        File agentJar = new File(javaHome + "/lib/agent.jar");
+        ClassLoader parentLoader = JmcAgentIntegrationTest.class.getClassLoader();
+        URLClassLoader agentLoader = new URLClassLoader(new URL[] {agentJar.toURI().toURL()}, parentLoader);
+        try {
+             Class.forName("org.openjdk.jmc.internal.org.objectweb.asm.Opcodes", true, agentLoader).getDeclaredField("V" + spec);
+        } catch (NoSuchFieldException e) {
+            System.out.println("Incompatible class file version. Skipping VM specific tests.");
+            testOptions.add("-vm-agnostic-tests");
+        }
+
+        URL url = jar.toURI().toURL();
+        String classPath = System.getProperty("java.class.path", ".");
+
+        System.setProperty("java.class.path", classPath + System.getProperty("path.separator") + jar.toString());
+        System.setProperty("useJmcAgentOption", "true");
+        System.setProperty("traceExecs", "true");
+
+        URLClassLoader cl = new URLClassLoader(new URL[] {url}, parentLoader);
+        Class<?> testClass = Class.forName("org.openjdk.jmc.agent.sap.test.TestRunner", true, cl);
+        Method mainMethod = testClass.getDeclaredMethod("main", String[].class, String[].class);
+        mainMethod.invoke(null, new Object[] {testOptions.toArray(new String[0]), new String[] {"-XX:+EnableDynamicAgentLoading"}});
+    }
+}