8317689: [JVMCI] include error message when CreateJavaVM in libgraal fails

Reviewed-by: phofer, thartmann, never

Author: Doug Simon

src/hotspot/share/compiler/compileBroker.cpp

@@ -2211,7 +2211,9 @@ void CompileBroker::invoke_compiler_on_method(CompileTask* task) {
     } else {
       JVMCIEnv env(thread, &compile_state, __FILE__, __LINE__);
       if (env.init_error() != JNI_OK) {
-        failure_reason = os::strdup(err_msg("Error attaching to libjvmci (err: %d)", env.init_error()), mtJVMCI);
+        const char* msg = env.init_error_msg();
+        failure_reason = os::strdup(err_msg("Error attaching to libjvmci (err: %d, %s)",
+                                    env.init_error(), msg == nullptr ? "unknown" : msg), mtJVMCI);
         bool reason_on_C_heap = true;
         // In case of JNI_ENOMEM, there's a good chance a subsequent attempt to create libjvmci or attach to it
         // might succeed. Other errors most likely indicate a non-recoverable error in the JVMCI runtime.

src/hotspot/share/jvmci/jvmciEnv.cpp

@@ -147,13 +147,14 @@ void JVMCIEnv::init_env_mode_runtime(JavaThread* thread, JNIEnv* parent_env) {
   _is_hotspot = false;
 
   _runtime = JVMCI::compiler_runtime(thread);
-  _env = _runtime->init_shared_library_javavm(&_init_error);
+  _env = _runtime->init_shared_library_javavm(&_init_error, &_init_error_msg);
   if (_env != nullptr) {
     // Creating the JVMCI shared library VM also attaches the current thread
     _detach_on_close = true;
   } else if (_init_error != JNI_OK) {
     // Caller creating this JVMCIEnv must handle the error.
-    JVMCI_event_1("[%s:%d] Error creating libjvmci (err: %d)", _file, _line, _init_error);
+    JVMCI_event_1("[%s:%d] Error creating libjvmci (err: %d, %s)", _file, _line,
+                  _init_error, _init_error_msg == nullptr ? "unknown" : _init_error_msg);
     return;
   } else {
     _runtime->GetEnv(thread, (void**)&parent_env, JNI_VERSION_1_2);
@@ -195,17 +196,17 @@ void JVMCIEnv::init_env_mode_runtime(JavaThread* thread, JNIEnv* parent_env) {
 }
 
 JVMCIEnv::JVMCIEnv(JavaThread* thread, JVMCICompileState* compile_state, const char* file, int line):
-    _throw_to_caller(false), _file(file), _line(line), _init_error(JNI_OK), _compile_state(compile_state) {
+    _throw_to_caller(false), _file(file), _line(line), _init_error(JNI_OK), _init_error_msg(nullptr), _compile_state(compile_state) {
   init_env_mode_runtime(thread, nullptr);
 }
 
 JVMCIEnv::JVMCIEnv(JavaThread* thread, const char* file, int line):
-    _throw_to_caller(false), _file(file), _line(line), _init_error(JNI_OK), _compile_state(nullptr) {
+    _throw_to_caller(false), _file(file), _line(line), _init_error(JNI_OK), _init_error_msg(nullptr), _compile_state(nullptr) {
   init_env_mode_runtime(thread, nullptr);
 }
 
 JVMCIEnv::JVMCIEnv(JavaThread* thread, JNIEnv* parent_env, const char* file, int line):
-    _throw_to_caller(true), _file(file), _line(line), _init_error(JNI_OK), _compile_state(nullptr) {
+    _throw_to_caller(true), _file(file), _line(line), _init_error(JNI_OK), _init_error_msg(nullptr), _compile_state(nullptr) {
   assert(parent_env != nullptr, "npe");
   init_env_mode_runtime(thread, parent_env);
   assert(_env == nullptr || parent_env == _env, "mismatched JNIEnvironment");
@@ -218,6 +219,7 @@ void JVMCIEnv::init(JavaThread* thread, bool is_hotspot, const char* file, int l
   _file = file;
   _line = line;
   _init_error = JNI_OK;
+  _init_error_msg = nullptr;
   if (is_hotspot) {
     _env = nullptr;
     _pop_frame_on_close = false;
@@ -237,7 +239,8 @@ void JVMCIEnv::check_init(JVMCI_TRAPS) {
   if (_init_error == JNI_ENOMEM) {
     JVMCI_THROW_MSG(OutOfMemoryError, "JNI_ENOMEM creating or attaching to libjvmci");
   }
-  JVMCI_THROW_MSG(InternalError, err_msg("Error creating or attaching to libjvmci (err: %d)", _init_error));
+  JVMCI_THROW_MSG(InternalError, err_msg("Error creating or attaching to libjvmci (err: %d, description: %s)",
+                  _init_error, _init_error_msg == nullptr ? "unknown" : _init_error_msg));
 }
 
 void JVMCIEnv::check_init(TRAPS) {
@@ -247,7 +250,8 @@ void JVMCIEnv::check_init(TRAPS) {
   if (_init_error == JNI_ENOMEM) {
     THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(), "JNI_ENOMEM creating or attaching to libjvmci");
   }
-  THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(), err_msg("Error creating or attaching to libjvmci (err: %d)", _init_error));
+  THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(), err_msg("Error creating or attaching to libjvmci (err: %d, description: %s)",
+            _init_error, _init_error_msg == nullptr ? "unknown" : _init_error_msg));
 }
 
 // Prints a pending exception (if any) and its stack trace to st.
@@ -572,6 +576,9 @@ jboolean JVMCIEnv::transfer_pending_exception(JavaThread* THREAD, JVMCIEnv* peer
 }
 
 JVMCIEnv::~JVMCIEnv() {
+  if (_init_error_msg != nullptr) {
+    os::free((void*) _init_error_msg);
+  }
   if (_init_error != JNI_OK) {
     return;
   }

src/hotspot/share/jvmci/jvmciEnv.hpp

@@ -172,6 +172,7 @@ class JVMCIEnv : public ResourceObj {
   int              _init_error;  // JNI code returned when creating or attaching to a libjvmci isolate.
                                  // If not JNI_OK, the JVMCIEnv is invalid and should not be used apart from
                                  // calling init_error().
+  const char*  _init_error_msg;  // Message for _init_error if available. C heap allocated.
 
   // Translates an exception on the HotSpot heap (i.e., hotspot_env) to an exception on
   // the shared library heap (i.e., jni_env). The translation includes the stack and cause(s) of `throwable`.
@@ -217,6 +218,12 @@ class JVMCIEnv : public ResourceObj {
     return _init_error;
   }
 
+  // Gets a message describing a non-zero init_error().
+  // Valid as long as this JVMCIEnv is valid.
+  const char* init_error_msg() {
+    return _init_error_msg;
+  }
+
   // Checks the value of init_error() and throws an exception in `JVMCI_TRAPS`
   // (which must not be this) if it is not JNI_OK.
   void check_init(JVMCI_TRAPS);

src/hotspot/share/jvmci/jvmciRuntime.cpp

@@ -1253,7 +1253,7 @@ bool JVMCIRuntime::detach_thread(JavaThread* thread, const char* reason, bool ca
   return destroyed_javavm;
 }
 
-JNIEnv* JVMCIRuntime::init_shared_library_javavm(int* create_JavaVM_err) {
+JNIEnv* JVMCIRuntime::init_shared_library_javavm(int* create_JavaVM_err, const char** err_msg) {
   MutexLocker locker(_lock);
   JavaVM* javaVM = _shared_library_javavm;
   if (javaVM == nullptr) {
@@ -1280,7 +1280,7 @@ JNIEnv* JVMCIRuntime::init_shared_library_javavm(int* create_JavaVM_err) {
     JavaVMInitArgs vm_args;
     vm_args.version = JNI_VERSION_1_2;
     vm_args.ignoreUnrecognized = JNI_TRUE;
-    JavaVMOption options[5];
+    JavaVMOption options[6];
     jlong javaVM_id = 0;
 
     // Protocol: JVMCI shared library JavaVM should support a non-standard "_javavm_id"
@@ -1297,6 +1297,8 @@ JNIEnv* JVMCIRuntime::init_shared_library_javavm(int* create_JavaVM_err) {
     options[3].extraInfo = (void*) _fatal;
     options[4].optionString = (char*) "_fatal_log";
     options[4].extraInfo = (void*) _fatal_log;
+    options[5].optionString = (char*) "_createvm_errorstr";
+    options[5].extraInfo = (void*) err_msg;
 
     vm_args.version = JNI_VERSION_1_2;
     vm_args.options = options;

src/hotspot/share/jvmci/jvmciRuntime.hpp

@@ -280,8 +280,10 @@ class JVMCIRuntime: public CHeapObj<mtJVMCI> {
   // If the JavaVM was created by this call, then the thread-local JNI
   // interface pointer for the JavaVM is returned otherwise null is returned.
   // If this method tried to create the JavaVM but failed, the error code returned
-  // by JNI_CreateJavaVM is returned in create_JavaVM_err.
-  JNIEnv* init_shared_library_javavm(int* create_JavaVM_err);
+  // by JNI_CreateJavaVM is returned in create_JavaVM_err and, if available, an
+  // error message is malloc'ed and assigned to err_msg. The caller is responsible
+  // for freeing err_msg.
+  JNIEnv* init_shared_library_javavm(int* create_JavaVM_err, const char** err_msg);
 
   // Determines if the JVMCI shared library JavaVM exists for this runtime.
   bool has_shared_library_javavm() { return _shared_library_javavm != nullptr; }

src/hotspot/share/prims/whitebox.cpp

@@ -381,7 +381,7 @@ WB_ENTRY(jboolean, WB_IsGCSupportedByJVMCICompiler(JNIEnv* env, jobject o, jint
   if (EnableJVMCI) {
     // Enter the JVMCI env that will be used by the CompileBroker.
     JVMCIEnv jvmciEnv(thread, __FILE__, __LINE__);
-    return jvmciEnv.runtime()->is_gc_supported(&jvmciEnv, (CollectedHeap::Name)name);
+    return jvmciEnv.init_error() == JNI_OK && jvmciEnv.runtime()->is_gc_supported(&jvmciEnv, (CollectedHeap::Name)name);
   }
 #endif
   return false;