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

 /*

  * Copyright (c) 2016, 2018, 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 "jni.h"

 #include "classfile/symbolTable.hpp"

 #include "classfile/systemDictionary.hpp"

 #include "classfile/vmSymbols.hpp"

 #include "jfr/jni/jfrJavaSupport.hpp"

 #include "jfr/recorder/storage/jfrStorage.hpp"

 #include "jfr/support/jfrThreadId.hpp"

 #include "jfr/utilities/jfrTypes.hpp"

 #include "jfr/writers/jfrJavaEventWriter.hpp"

 #include "oops/instanceKlass.hpp"

 #include "oops/oop.inline.hpp"

 #include "runtime/fieldDescriptor.hpp"

 #include "runtime/handles.hpp"

 #include "runtime/jniHandles.hpp"

 #include "runtime/thread.inline.hpp"

 static int start_pos_offset = invalid_offset;

 static int start_pos_address_offset = invalid_offset;

 static int current_pos_offset = invalid_offset;

 static int max_pos_offset = invalid_offset;

 static int max_event_size_offset = invalid_offset;

 static int notified_offset = invalid_offset;

 static int thread_id_offset = invalid_offset;

 static int valid_offset = invalid_offset;

 static bool find_field(InstanceKlass* ik,

                        Symbol* name_symbol,

                        Symbol* signature_symbol,

                        fieldDescriptor* fd,

                        bool is_static = false,

                        bool allow_super = false) {

   if (allow_super || is_static) {

     return ik->find_field(name_symbol, signature_symbol, is_static, fd) != NULL;

   } else {

     return ik->find_local_field(name_symbol, signature_symbol, fd);

   }

 }

 static void compute_offset(int &dest_offset,

                            Klass* klass,

                            Symbol* name_symbol,

                            Symbol* signature_symbol,

                            bool is_static = false, bool allow_super = false) {

   fieldDescriptor fd;

   InstanceKlass* ik = InstanceKlass::cast(klass);

   if (!find_field(ik, name_symbol, signature_symbol, &fd, is_static, allow_super)) {

     assert(false, "invariant");

   }

   dest_offset = fd.offset();

 }

 static bool setup_event_writer_offsets(TRAPS) {

   const char class_name[] = "jdk/jfr/internal/EventWriter";

   Symbol* const k_sym = SymbolTable::lookup(class_name, sizeof class_name - 1, CHECK_false);

   assert(k_sym != NULL, "invariant");

   Klass* klass = SystemDictionary::resolve_or_fail(k_sym, true, CHECK_false);

   assert(klass != NULL, "invariant");

   const char start_pos_name[] = "startPosition";

   Symbol* const start_pos_sym = SymbolTable::lookup(start_pos_name, sizeof start_pos_name - 1, CHECK_false);

   assert(start_pos_sym != NULL, "invariant");

   assert(invalid_offset == start_pos_offset, "invariant");

   compute_offset(start_pos_offset, klass, start_pos_sym, vmSymbols::long_signature());

   assert(start_pos_offset != invalid_offset, "invariant");

   const char start_pos_address_name[] = "startPositionAddress";

   Symbol* const start_pos_address_sym = SymbolTable::lookup(start_pos_address_name, sizeof start_pos_address_name - 1, CHECK_false);

   assert(start_pos_address_sym != NULL, "invariant");

   assert(invalid_offset == start_pos_address_offset, "invariant");

   compute_offset(start_pos_address_offset, klass, start_pos_address_sym, vmSymbols::long_signature());

   assert(start_pos_address_offset != invalid_offset, "invariant");

   const char event_pos_name[] = "currentPosition";

   Symbol* const event_pos_sym = SymbolTable::lookup(event_pos_name, sizeof event_pos_name - 1, CHECK_false);

   assert(event_pos_sym != NULL, "invariant");

   assert(invalid_offset == current_pos_offset, "invariant");

   compute_offset(current_pos_offset, klass, event_pos_sym,vmSymbols::long_signature());

   assert(current_pos_offset != invalid_offset, "invariant");

   const char max_pos_name[] = "maxPosition";

   Symbol* const max_pos_sym = SymbolTable::lookup(max_pos_name, sizeof max_pos_name - 1, CHECK_false);

   assert(max_pos_sym != NULL, "invariant");

   assert(invalid_offset == max_pos_offset, "invariant");

   compute_offset(max_pos_offset, klass, max_pos_sym, vmSymbols::long_signature());

   assert(max_pos_offset != invalid_offset, "invariant");

   const char max_event_size_name[] = "maxEventSize";

   Symbol* const max_event_size_sym = SymbolTable::lookup(max_event_size_name, sizeof max_event_size_name - 1, CHECK_false);

   assert (max_event_size_sym != NULL, "invariant");

   assert(invalid_offset == max_event_size_offset, "invariant");

   compute_offset(max_event_size_offset, klass, max_event_size_sym, vmSymbols::int_signature());

   assert(max_event_size_offset != invalid_offset, "invariant");

   const char notified_name[] = "notified";

   Symbol* const notified_sym = SymbolTable::lookup(notified_name, sizeof notified_name - 1, CHECK_false);

   assert (notified_sym != NULL, "invariant");

   assert(invalid_offset == notified_offset, "invariant");

   compute_offset(notified_offset, klass, notified_sym, vmSymbols::bool_signature());

   assert(notified_offset != invalid_offset, "invariant");

   const char valid_name[] = "valid";

   Symbol* const valid_sym = SymbolTable::lookup(valid_name, sizeof valid_name - 1, CHECK_false);

   assert (valid_sym != NULL, "invariant");

   assert(invalid_offset == valid_offset, "invariant");

   compute_offset(valid_offset, klass, valid_sym, vmSymbols::bool_signature());

   assert(valid_offset != invalid_offset, "invariant");

   return true;

 }

 bool JfrJavaEventWriter::has_required_classes(TRAPS) {

   const char class_name[] = "jdk/jfr/internal/EventWriter";

   Symbol* const k_sym = SymbolTable::lookup(class_name, sizeof class_name - 1, CHECK_false);

   Klass* klass = SystemDictionary::resolve_or_null(k_sym, CHECK_false);

   return (klass != NULL);

 }

 bool JfrJavaEventWriter::initialize() {

   static bool initialized = false;

   if (!initialized) {

     Thread* thread = Thread::current();

     initialized = setup_event_writer_offsets(thread);

   }

   return initialized;

 }

 jboolean JfrJavaEventWriter::flush(jobject writer, jint used, jint requested, JavaThread* jt) {

   DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(jt));

   assert(writer != NULL, "invariant");

   oop const w = JNIHandles::resolve_non_null(writer);

   assert(w != NULL, "invariant");

   JfrBuffer* const current = jt->jfr_thread_local()->java_buffer();

   assert(current != NULL, "invariant");

   JfrBuffer* const buffer = JfrStorage::flush(current, used, requested, false, jt);

   assert(buffer != NULL, "invariant");

   // "validity" is contextually defined here to mean

   // that some memory location was provided that is

   // large enough to accommodate the "requested size".

   const bool is_valid = buffer->free_size() >= (size_t)(used + requested);

   u1* const new_current_position = is_valid ? buffer->pos() + used : buffer->pos();

   w->long_field_put(start_pos_offset, (jlong)buffer->pos());

   w->long_field_put(current_pos_offset, (jlong)new_current_position);

   // only update java writer if underlying memory changed

   if (buffer != current) {

     w->long_field_put(start_pos_address_offset, (jlong)buffer->pos_address());

     w->long_field_put(max_pos_offset, (jlong)buffer->end());

   }

   if (!is_valid) {

     // mark writer as invalid for this write attempt

     w->release_bool_field_put(valid_offset, JNI_FALSE);

     return JNI_FALSE;

   }

   // An exclusive use of a leased buffer is treated equivalent to

   // holding a system resource. As such, it should be released as soon as possible.

   // Returning true here signals that the thread will need to call flush again

   // on EventWriter.endEvent() and that flush will return the lease.

   return buffer->lease() ? JNI_TRUE : JNI_FALSE;

 }

 class JfrJavaEventWriterNotificationClosure : public ThreadClosure {

  public:

    void do_thread(Thread* t) {

      if (t->is_Java_thread()) {

        JfrJavaEventWriter::notify((JavaThread*)t);

      }

    }

 };

 void JfrJavaEventWriter::notify() {

   assert(SafepointSynchronize::is_at_safepoint(), "invariant");

   JfrJavaEventWriterNotificationClosure closure;

   Threads::threads_do(&closure);

 }

 void JfrJavaEventWriter::notify(JavaThread* jt) {

   assert(jt != NULL, "invariant");

   assert(SafepointSynchronize::is_at_safepoint(), "invariant");

   if (jt->jfr_thread_local()->has_java_event_writer()) {

     oop buffer_writer = JNIHandles::resolve_non_null(jt->jfr_thread_local()->java_event_writer());

     assert(buffer_writer != NULL, "invariant");

     buffer_writer->release_bool_field_put(notified_offset, JNI_TRUE);

   }

 }

 static jobject create_new_event_writer(JfrBuffer* buffer, TRAPS) {

   assert(buffer != NULL, "invariant");

   DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(THREAD));

   HandleMark hm(THREAD);

   static const char klass[] = "jdk/jfr/internal/EventWriter";

   static const char method[] = "<init>";

   static const char signature[] = "(JJJJZ)V";

   JavaValue result(T_OBJECT);

   JfrJavaArguments args(&result, klass, method, signature, CHECK_NULL);

   // parameters

   args.push_long((jlong)buffer->pos());

   args.push_long((jlong)buffer->end());

   args.push_long((jlong)buffer->pos_address());

   args.push_long((jlong)JFR_THREAD_ID(THREAD));

   args.push_int((int)JNI_TRUE);

   JfrJavaSupport::new_object_global_ref(&args, CHECK_NULL);

   return result.get_jobject();

 }

 jobject JfrJavaEventWriter::event_writer(Thread* t) {

   DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(t));

   JfrThreadLocal* const tl = t->jfr_thread_local();

   assert(tl->shelved_buffer() == NULL, "invariant");

   return tl->java_event_writer();

 }

 jobject JfrJavaEventWriter::new_event_writer(TRAPS) {

   DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(THREAD));

   assert(event_writer(THREAD) == NULL, "invariant");

   JfrThreadLocal* const tl = THREAD->jfr_thread_local();

   assert(!tl->has_java_buffer(), "invariant");

   JfrBuffer* const buffer = tl->java_buffer();

   if (buffer == NULL) {

     JfrJavaSupport::throw_out_of_memory_error("OOME for thread local buffer", THREAD);

     return NULL;

   }

   jobject java_event_writer = create_new_event_writer(buffer, CHECK_NULL);

   tl->set_java_event_writer(java_event_writer);

   assert(tl->has_java_event_writer(), "invariant");

   return java_event_writer;

 }