Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright (c) 2005, 2011, 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 klassOop load_and_initialize_klass(Symbol* sh, TRAPS) {

   klassOop 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();

   klassOop 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(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;

 }

 #ifndef SERVICES_KERNEL   // Heap dumping not supported

 // 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;

 }

 #endif // SERVICES_KERNEL

 // 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 */, true /* need_prologue */);

   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, 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, 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;

     }

   }

   bool res = CommandLineFlags::uintxAtPut((char*)name, &value, 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, 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, ATTACH_ON_DEMAND);

   if (res) {

     FREE_C_HEAP_ARRAY(char, value);

   } 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->print_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 },

 #ifndef SERVICES_KERNEL

   { "dumpheap",         dump_heap },

 #endif  // SERVICES_KERNEL

   { "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);

   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;

   klassOop 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,

                        CHECK);

   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

                         CHECK);

   { 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();

 }