Mercurial > hg > graal-compiler
view src/share/vm/services/attachListener.cpp @ 20279:870c03421152
8049426: Minor cleanups after G1 class unloading
Reviewed-by: stefank, brutisso
author | ehelin |
---|---|
date | Wed, 09 Jul 2014 16:44:30 +0200 |
parents | 78bbf4d43a14 |
children | 52b4284cb496 2545e461115b |
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/* * Copyright (c) 2005, 2014, Oracle and/or its affiliates. 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. * */ #include "precompiled.hpp" #include "classfile/javaClasses.hpp" #include "classfile/systemDictionary.hpp" #include "gc_implementation/shared/vmGCOperations.hpp" #include "memory/resourceArea.hpp" #include "prims/jvmtiExport.hpp" #include "runtime/arguments.hpp" #include "runtime/globals.hpp" #include "runtime/java.hpp" #include "runtime/javaCalls.hpp" #include "runtime/os.hpp" #include "services/attachListener.hpp" #include "services/diagnosticCommand.hpp" #include "services/heapDumper.hpp" volatile bool AttachListener::_initialized; // Implementation of "properties" command. // // Invokes sun.misc.VMSupport.serializePropertiesToByteArray to serialize // the system properties into a byte array. static Klass* load_and_initialize_klass(Symbol* sh, TRAPS) { Klass* k = SystemDictionary::resolve_or_fail(sh, true, CHECK_NULL); instanceKlassHandle ik (THREAD, k); if (ik->should_be_initialized()) { ik->initialize(CHECK_NULL); } return ik(); } static jint get_properties(AttachOperation* op, outputStream* out, Symbol* serializePropertiesMethod) { Thread* THREAD = Thread::current(); HandleMark hm; // load sun.misc.VMSupport Symbol* klass = vmSymbols::sun_misc_VMSupport(); Klass* k = load_and_initialize_klass(klass, THREAD); if (HAS_PENDING_EXCEPTION) { java_lang_Throwable::print(PENDING_EXCEPTION, out); CLEAR_PENDING_EXCEPTION; return JNI_ERR; } instanceKlassHandle ik(THREAD, k); // invoke the serializePropertiesToByteArray method JavaValue result(T_OBJECT); JavaCallArguments args; Symbol* signature = vmSymbols::serializePropertiesToByteArray_signature(); JavaCalls::call_static(&result, ik, serializePropertiesMethod, signature, &args, THREAD); if (HAS_PENDING_EXCEPTION) { java_lang_Throwable::print(PENDING_EXCEPTION, out); CLEAR_PENDING_EXCEPTION; return JNI_ERR; } // The result should be a [B oop res = (oop)result.get_jobject(); assert(res->is_typeArray(), "just checking"); assert(TypeArrayKlass::cast(res->klass())->element_type() == T_BYTE, "just checking"); // copy the bytes to the output stream typeArrayOop ba = typeArrayOop(res); jbyte* addr = typeArrayOop(res)->byte_at_addr(0); out->print_raw((const char*)addr, ba->length()); return JNI_OK; } // Implementation of "properties" command. // See also: PrintSystemPropertiesDCmd class static jint get_system_properties(AttachOperation* op, outputStream* out) { return get_properties(op, out, vmSymbols::serializePropertiesToByteArray_name()); } // Implementation of "agent_properties" command. static jint get_agent_properties(AttachOperation* op, outputStream* out) { return get_properties(op, out, vmSymbols::serializeAgentPropertiesToByteArray_name()); } // Implementation of "datadump" command. // // Raises a SIGBREAK signal so that VM dump threads, does deadlock detection, // etc. In theory this command should only post a DataDumpRequest to any // JVMTI environment that has enabled this event. However it's useful to // trigger the SIGBREAK handler. static jint data_dump(AttachOperation* op, outputStream* out) { if (!ReduceSignalUsage) { AttachListener::pd_data_dump(); } else { if (JvmtiExport::should_post_data_dump()) { JvmtiExport::post_data_dump(); } } return JNI_OK; } // Implementation of "threaddump" command - essentially a remote ctrl-break // See also: ThreadDumpDCmd class // static jint thread_dump(AttachOperation* op, outputStream* out) { bool print_concurrent_locks = false; if (op->arg(0) != NULL && strcmp(op->arg(0), "-l") == 0) { print_concurrent_locks = true; } // thread stacks VM_PrintThreads op1(out, print_concurrent_locks); VMThread::execute(&op1); // JNI global handles VM_PrintJNI op2(out); VMThread::execute(&op2); // Deadlock detection VM_FindDeadlocks op3(out); VMThread::execute(&op3); return JNI_OK; } // A jcmd attach operation request was received, which will now // dispatch to the diagnostic commands used for serviceability functions. static jint jcmd(AttachOperation* op, outputStream* out) { Thread* THREAD = Thread::current(); // All the supplied jcmd arguments are stored as a single // string (op->arg(0)). This is parsed by the Dcmd framework. DCmd::parse_and_execute(DCmd_Source_AttachAPI, out, op->arg(0), ' ', THREAD); if (HAS_PENDING_EXCEPTION) { java_lang_Throwable::print(PENDING_EXCEPTION, out); out->cr(); CLEAR_PENDING_EXCEPTION; // The exception has been printed on the output stream // If the JVM returns JNI_ERR, the attachAPI throws a generic I/O // exception and the content of the output stream is not processed. // By returning JNI_OK, the exception will be displayed on the client side } return JNI_OK; } // Implementation of "dumpheap" command. // See also: HeapDumpDCmd class // // Input arguments :- // arg0: Name of the dump file // arg1: "-live" or "-all" jint dump_heap(AttachOperation* op, outputStream* out) { const char* path = op->arg(0); if (path == NULL || path[0] == '\0') { out->print_cr("No dump file specified"); } else { bool live_objects_only = true; // default is true to retain the behavior before this change is made const char* arg1 = op->arg(1); if (arg1 != NULL && (strlen(arg1) > 0)) { if (strcmp(arg1, "-all") != 0 && strcmp(arg1, "-live") != 0) { out->print_cr("Invalid argument to dumpheap operation: %s", arg1); return JNI_ERR; } live_objects_only = strcmp(arg1, "-live") == 0; } // Request a full GC before heap dump if live_objects_only = true // This helps reduces the amount of unreachable objects in the dump // and makes it easier to browse. HeapDumper dumper(live_objects_only /* request GC */); int res = dumper.dump(op->arg(0)); if (res == 0) { out->print_cr("Heap dump file created"); } else { // heap dump failed ResourceMark rm; char* error = dumper.error_as_C_string(); if (error == NULL) { out->print_cr("Dump failed - reason unknown"); } else { out->print_cr("%s", error); } } } return JNI_OK; } // Implementation of "inspectheap" command // See also: ClassHistogramDCmd class // // Input arguments :- // arg0: "-live" or "-all" static jint heap_inspection(AttachOperation* op, outputStream* out) { bool live_objects_only = true; // default is true to retain the behavior before this change is made const char* arg0 = op->arg(0); if (arg0 != NULL && (strlen(arg0) > 0)) { if (strcmp(arg0, "-all") != 0 && strcmp(arg0, "-live") != 0) { out->print_cr("Invalid argument to inspectheap operation: %s", arg0); return JNI_ERR; } live_objects_only = strcmp(arg0, "-live") == 0; } VM_GC_HeapInspection heapop(out, live_objects_only /* request full gc */); VMThread::execute(&heapop); return JNI_OK; } // set a boolean global flag using value from AttachOperation static jint set_bool_flag(const char* name, AttachOperation* op, outputStream* out) { bool value = true; const char* arg1; if ((arg1 = op->arg(1)) != NULL) { int tmp; int n = sscanf(arg1, "%d", &tmp); if (n != 1) { out->print_cr("flag value must be a boolean (1 or 0)"); return JNI_ERR; } value = (tmp != 0); } bool res = CommandLineFlags::boolAtPut((char*)name, &value, Flag::ATTACH_ON_DEMAND); if (! res) { out->print_cr("setting flag %s failed", name); } return res? JNI_OK : JNI_ERR; } // set a intx global flag using value from AttachOperation static jint set_intx_flag(const char* name, AttachOperation* op, outputStream* out) { intx value; const char* arg1; if ((arg1 = op->arg(1)) != NULL) { int n = sscanf(arg1, INTX_FORMAT, &value); if (n != 1) { out->print_cr("flag value must be an integer"); return JNI_ERR; } } bool res = CommandLineFlags::intxAtPut((char*)name, &value, Flag::ATTACH_ON_DEMAND); if (! res) { out->print_cr("setting flag %s failed", name); } return res? JNI_OK : JNI_ERR; } // set a uintx global flag using value from AttachOperation static jint set_uintx_flag(const char* name, AttachOperation* op, outputStream* out) { uintx value; const char* arg1; if ((arg1 = op->arg(1)) != NULL) { int n = sscanf(arg1, UINTX_FORMAT, &value); if (n != 1) { out->print_cr("flag value must be an unsigned integer"); return JNI_ERR; } } if (strncmp(name, "MaxHeapFreeRatio", 17) == 0) { FormatBuffer<80> err_msg("%s", ""); if (!Arguments::verify_MaxHeapFreeRatio(err_msg, value)) { out->print_cr("%s", err_msg.buffer()); return JNI_ERR; } } else if (strncmp(name, "MinHeapFreeRatio", 17) == 0) { FormatBuffer<80> err_msg("%s", ""); if (!Arguments::verify_MinHeapFreeRatio(err_msg, value)) { out->print_cr("%s", err_msg.buffer()); return JNI_ERR; } } bool res = CommandLineFlags::uintxAtPut((char*)name, &value, Flag::ATTACH_ON_DEMAND); if (! res) { out->print_cr("setting flag %s failed", name); } return res? JNI_OK : JNI_ERR; } // set a uint64_t global flag using value from AttachOperation static jint set_uint64_t_flag(const char* name, AttachOperation* op, outputStream* out) { uint64_t value; const char* arg1; if ((arg1 = op->arg(1)) != NULL) { int n = sscanf(arg1, UINT64_FORMAT, &value); if (n != 1) { out->print_cr("flag value must be an unsigned 64-bit integer"); return JNI_ERR; } } bool res = CommandLineFlags::uint64_tAtPut((char*)name, &value, Flag::ATTACH_ON_DEMAND); if (! res) { out->print_cr("setting flag %s failed", name); } return res? JNI_OK : JNI_ERR; } // set a string global flag using value from AttachOperation static jint set_ccstr_flag(const char* name, AttachOperation* op, outputStream* out) { const char* value; if ((value = op->arg(1)) == NULL) { out->print_cr("flag value must be a string"); return JNI_ERR; } bool res = CommandLineFlags::ccstrAtPut((char*)name, &value, Flag::ATTACH_ON_DEMAND); if (res) { FREE_C_HEAP_ARRAY(char, value, mtInternal); } else { out->print_cr("setting flag %s failed", name); } return res? JNI_OK : JNI_ERR; } // Implementation of "setflag" command static jint set_flag(AttachOperation* op, outputStream* out) { const char* name = NULL; if ((name = op->arg(0)) == NULL) { out->print_cr("flag name is missing"); return JNI_ERR; } Flag* f = Flag::find_flag((char*)name, strlen(name)); if (f && f->is_external() && f->is_writeable()) { if (f->is_bool()) { return set_bool_flag(name, op, out); } else if (f->is_intx()) { return set_intx_flag(name, op, out); } else if (f->is_uintx()) { return set_uintx_flag(name, op, out); } else if (f->is_uint64_t()) { return set_uint64_t_flag(name, op, out); } else if (f->is_ccstr()) { return set_ccstr_flag(name, op, out); } else { ShouldNotReachHere(); return JNI_ERR; } } else { return AttachListener::pd_set_flag(op, out); } } // Implementation of "printflag" command // See also: PrintVMFlagsDCmd class static jint print_flag(AttachOperation* op, outputStream* out) { const char* name = NULL; if ((name = op->arg(0)) == NULL) { out->print_cr("flag name is missing"); return JNI_ERR; } Flag* f = Flag::find_flag((char*)name, strlen(name)); if (f) { f->print_as_flag(out); out->cr(); } else { out->print_cr("no such flag '%s'", name); } return JNI_OK; } // Table to map operation names to functions. // names must be of length <= AttachOperation::name_length_max static AttachOperationFunctionInfo funcs[] = { { "agentProperties", get_agent_properties }, { "datadump", data_dump }, { "dumpheap", dump_heap }, { "load", JvmtiExport::load_agent_library }, { "properties", get_system_properties }, { "threaddump", thread_dump }, { "inspectheap", heap_inspection }, { "setflag", set_flag }, { "printflag", print_flag }, { "jcmd", jcmd }, { NULL, NULL } }; // The Attach Listener threads services a queue. It dequeues an operation // from the queue, examines the operation name (command), and dispatches // to the corresponding function to perform the operation. static void attach_listener_thread_entry(JavaThread* thread, TRAPS) { os::set_priority(thread, NearMaxPriority); thread->record_stack_base_and_size(); if (AttachListener::pd_init() != 0) { return; } AttachListener::set_initialized(); for (;;) { AttachOperation* op = AttachListener::dequeue(); if (op == NULL) { return; // dequeue failed or shutdown } ResourceMark rm; bufferedStream st; jint res = JNI_OK; // handle special detachall operation if (strcmp(op->name(), AttachOperation::detachall_operation_name()) == 0) { AttachListener::detachall(); } else { // find the function to dispatch too AttachOperationFunctionInfo* info = NULL; for (int i=0; funcs[i].name != NULL; i++) { const char* name = funcs[i].name; assert(strlen(name) <= AttachOperation::name_length_max, "operation <= name_length_max"); if (strcmp(op->name(), name) == 0) { info = &(funcs[i]); break; } } // check for platform dependent attach operation if (info == NULL) { info = AttachListener::pd_find_operation(op->name()); } if (info != NULL) { // dispatch to the function that implements this operation res = (info->func)(op, &st); } else { st.print("Operation %s not recognized!", op->name()); res = JNI_ERR; } } // operation complete - send result and output to client op->complete(res, &st); } } // Starts the Attach Listener thread void AttachListener::init() { EXCEPTION_MARK; Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_Thread(), true, CHECK); instanceKlassHandle klass (THREAD, k); instanceHandle thread_oop = klass->allocate_instance_handle(CHECK); const char thread_name[] = "Attach Listener"; Handle string = java_lang_String::create_from_str(thread_name, CHECK); // Initialize thread_oop to put it into the system threadGroup Handle thread_group (THREAD, Universe::system_thread_group()); JavaValue result(T_VOID); JavaCalls::call_special(&result, thread_oop, klass, vmSymbols::object_initializer_name(), vmSymbols::threadgroup_string_void_signature(), thread_group, string, THREAD); if (HAS_PENDING_EXCEPTION) { tty->print_cr("Exception in VM (AttachListener::init) : "); java_lang_Throwable::print(PENDING_EXCEPTION, tty); tty->cr(); CLEAR_PENDING_EXCEPTION; return; } KlassHandle group(THREAD, SystemDictionary::ThreadGroup_klass()); JavaCalls::call_special(&result, thread_group, group, vmSymbols::add_method_name(), vmSymbols::thread_void_signature(), thread_oop, // ARG 1 THREAD); if (HAS_PENDING_EXCEPTION) { tty->print_cr("Exception in VM (AttachListener::init) : "); java_lang_Throwable::print(PENDING_EXCEPTION, tty); tty->cr(); CLEAR_PENDING_EXCEPTION; return; } { MutexLocker mu(Threads_lock); JavaThread* listener_thread = new JavaThread(&attach_listener_thread_entry); // Check that thread and osthread were created if (listener_thread == NULL || listener_thread->osthread() == NULL) { vm_exit_during_initialization("java.lang.OutOfMemoryError", "unable to create new native thread"); } java_lang_Thread::set_thread(thread_oop(), listener_thread); java_lang_Thread::set_daemon(thread_oop()); listener_thread->set_threadObj(thread_oop()); Threads::add(listener_thread); Thread::start(listener_thread); } } // Performs clean-up tasks on platforms where we can detect that the last // client has detached void AttachListener::detachall() { // call the platform dependent clean-up pd_detachall(); }