--- a/src/hotspot/share/jfr/recorder/checkpoint/jfrMetadataEvent.cpp Wed Oct 30 16:14:56 2019 +0100
+++ b/src/hotspot/share/jfr/recorder/checkpoint/jfrMetadataEvent.cpp Wed Oct 30 19:43:52 2019 +0100
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016, 2019, 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
@@ -29,61 +29,53 @@
#include "oops/klass.inline.hpp"
#include "oops/oop.inline.hpp"
#include "oops/typeArrayOop.inline.hpp"
-#include "runtime/semaphore.hpp"
#include "runtime/thread.inline.hpp"
-static jbyteArray _metadata_blob = NULL;
-static Semaphore metadata_mutex_semaphore(1);
+static jbyteArray metadata_blob = NULL;
+static u8 metadata_id = 0;
+static u8 last_metadata_id = 0;
-void JfrMetadataEvent::lock() {
- metadata_mutex_semaphore.wait();
-}
-
-void JfrMetadataEvent::unlock() {
- metadata_mutex_semaphore.signal();
+static void write_metadata_blob(JfrChunkWriter& chunkwriter) {
+ assert(metadata_blob != NULL, "invariant");
+ const typeArrayOop arr = (typeArrayOop)JfrJavaSupport::resolve_non_null(metadata_blob);
+ assert(arr != NULL, "invariant");
+ const int length = arr->length();
+ const Klass* const k = arr->klass();
+ assert(k != NULL && k->is_array_klass(), "invariant");
+ const TypeArrayKlass* const byte_arr_klass = TypeArrayKlass::cast(k);
+ const jbyte* const data_address = arr->byte_at_addr(0);
+ chunkwriter.write_unbuffered(data_address, length);
}
-static void write_metadata_blob(JfrChunkWriter& chunkwriter, jbyteArray metadata_blob) {
- if (metadata_blob != NULL) {
- const typeArrayOop arr = (typeArrayOop)JfrJavaSupport::resolve_non_null(metadata_blob);
- assert(arr != NULL, "invariant");
- const int length = arr->length();
- const Klass* const k = arr->klass();
- assert(k != NULL && k->is_array_klass(), "invariant");
- const TypeArrayKlass* const byte_arr_klass = TypeArrayKlass::cast(k);
- const jbyte* const data_address = arr->byte_at_addr(0);
- chunkwriter.write_unbuffered(data_address, length);
+void JfrMetadataEvent::write(JfrChunkWriter& chunkwriter) {
+ assert(chunkwriter.is_valid(), "invariant");
+ if (last_metadata_id == metadata_id && chunkwriter.has_metadata()) {
+ return;
}
-}
-
-// the semaphore is assumed to be locked (was locked previous safepoint)
-size_t JfrMetadataEvent::write(JfrChunkWriter& chunkwriter, jlong metadata_offset) {
- assert(chunkwriter.is_valid(), "invariant");
- assert(chunkwriter.current_offset() == metadata_offset, "invariant");
// header
- chunkwriter.reserve(sizeof(u4));
+ const int64_t metadata_offset = chunkwriter.reserve(sizeof(u4));
chunkwriter.write<u8>(EVENT_METADATA); // ID 0
// time data
chunkwriter.write(JfrTicks::now());
chunkwriter.write((u8)0); // duration
- chunkwriter.write((u8)0); // metadata id
- write_metadata_blob(chunkwriter, _metadata_blob); // payload
- unlock(); // open up for java to provide updated metadata
+ chunkwriter.write(metadata_id); // metadata id
+ write_metadata_blob(chunkwriter); // payload
// fill in size of metadata descriptor event
- const jlong size_written = chunkwriter.current_offset() - metadata_offset;
+ const int64_t size_written = chunkwriter.current_offset() - metadata_offset;
chunkwriter.write_padded_at_offset((u4)size_written, metadata_offset);
- return size_written;
+ chunkwriter.set_last_metadata_offset(metadata_offset);
+ last_metadata_id = metadata_id;
}
void JfrMetadataEvent::update(jbyteArray metadata) {
JavaThread* thread = (JavaThread*)Thread::current();
assert(thread->is_Java_thread(), "invariant");
DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(thread));
- lock();
- if (_metadata_blob != NULL) {
- JfrJavaSupport::destroy_global_jni_handle(_metadata_blob);
+ if (metadata_blob != NULL) {
+ JfrJavaSupport::destroy_global_jni_handle(metadata_blob);
}
const oop new_desc_oop = JfrJavaSupport::resolve_non_null(metadata);
- _metadata_blob = new_desc_oop != NULL ? (jbyteArray)JfrJavaSupport::global_jni_handle(new_desc_oop, thread) : NULL;
- unlock();
+ assert(new_desc_oop != NULL, "invariant");
+ metadata_blob = (jbyteArray)JfrJavaSupport::global_jni_handle(new_desc_oop, thread);
+ ++metadata_id;
}