jdk8-mips64-public/hotspot: comparison src/share/vm/utilities/events.hpp

--1:000000000000
+:f90c822e73f8
+/*
+* Copyright (c) 1997, 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.
+*
+*/
+#ifndef SHARE_VM_UTILITIES_EVENTS_HPP
+#define SHARE_VM_UTILITIES_EVENTS_HPP
+#include "memory/allocation.hpp"
+#include "runtime/mutexLocker.hpp"
+#include "runtime/thread.hpp"
+#include "utilities/top.hpp"
+#include "utilities/vmError.hpp"
+// Events and EventMark provide interfaces to log events taking place in the vm.
+// This facility is extremly useful for post-mortem debugging. The eventlog
+// often provides crucial information about events leading up to the crash.
+//
+// Abstractly the logs can record whatever they way but normally they
+// would record at least a timestamp and the current Thread, along
+// with whatever data they need in a ring buffer.  Commonly fixed
+// length text messages are recorded for simplicity but other
+// strategies could be used.  Several logs are provided by default but
+// new instances can be created as needed.
+// The base event log dumping class that is registered for dumping at
+// crash time.  This is a very generic interface that is mainly here
+// for completeness.  Normally the templated EventLogBase would be
+// subclassed to provide different log types.
+class EventLog : public CHeapObj<mtInternal> {
+friend class Events;
+private:
+EventLog* _next;
+EventLog* next() const { return _next; }
+public:
+// Automatically registers the log so that it will be printed during
+// crashes.
+EventLog();
+virtual void print_log_on(outputStream* out) = 0;
+};
+// A templated subclass of EventLog that provides basic ring buffer
+// functionality.  Most event loggers should subclass this, possibly
+// providing a more featureful log function if the existing copy
+// semantics aren't appropriate.  The name is used as the label of the
+// log when it is dumped during a crash.
+template <class T> class EventLogBase : public EventLog {
+template <class X> class EventRecord : public CHeapObj<mtInternal> {
+public:
+double  timestamp;
+Thread* thread;
+X       data;
+};
+protected:
+Mutex           _mutex;
+const char*     _name;
+int             _length;
+int             _index;
+int             _count;
+EventRecord<T>* _records;
+public:
+EventLogBase<T>(const char* name, int length = LogEventsBufferEntries):
+_name(name),
+_length(length),
+_count(0),
+_index(0),
+_mutex(Mutex::event, name) {
+_records = new EventRecord<T>[length];
+}
+double fetch_timestamp() {
+return os::elapsedTime();
+}
+// move the ring buffer to next open slot and return the index of
+// the slot to use for the current message.  Should only be called
+// while mutex is held.
+int compute_log_index() {
+int index = _index;
+if (_count < _length) _count++;
+_index++;
+if (_index >= _length) _index = 0;
+return index;
+}
+bool should_log() {
+// Don't bother adding new entries when we're crashing.  This also
+// avoids mutating the ring buffer when printing the log.
+return !VMError::fatal_error_in_progress();
+}
+// Print the contents of the log
+void print_log_on(outputStream* out);
+private:
+void print_log_impl(outputStream* out);
+// Print a single element.  A templated implementation might need to
+// be declared by subclasses.
+void print(outputStream* out, T& e);
+void print(outputStream* out, EventRecord<T>& e) {
+out->print("Event: %.3f ", e.timestamp);
+if (e.thread != NULL) {
+out->print("Thread " INTPTR_FORMAT " ", p2i(e.thread));
+}
+print(out, e.data);
+}
+};
+// A simple wrapper class for fixed size text messages.
+class StringLogMessage : public FormatBuffer<256> {
+public:
+// Wrap this buffer in a stringStream.
+stringStream stream() {
+return stringStream(_buf, size());
+}
+};
+// A simple ring buffer of fixed size text messages.
+class StringEventLog : public EventLogBase<StringLogMessage> {
+public:
+StringEventLog(const char* name, int count = LogEventsBufferEntries) : EventLogBase<StringLogMessage>(name, count) {}
+void logv(Thread* thread, const char* format, va_list ap) ATTRIBUTE_PRINTF(3, 0) {
+if (!should_log()) return;
+double timestamp = fetch_timestamp();
+MutexLockerEx ml(&_mutex, Mutex::_no_safepoint_check_flag);
+int index = compute_log_index();
+_records[index].thread = thread;
+_records[index].timestamp = timestamp;
+_records[index].data.printv(format, ap);
+}
+void log(Thread* thread, const char* format, ...) ATTRIBUTE_PRINTF(3, 4) {
+va_list ap;
+va_start(ap, format);
+logv(thread, format, ap);
+va_end(ap);
+}
+};
+class Events : AllStatic {
+friend class EventLog;
+private:
+static EventLog* _logs;
+// A log for generic messages that aren't well categorized.
+static StringEventLog* _messages;
+// A log for internal exception related messages, like internal
+// throws and implicit exceptions.
+static StringEventLog* _exceptions;
+// Deoptization related messages
+static StringEventLog* _deopt_messages;
+public:
+static void print_all(outputStream* out);
+// Dump all events to the tty
+static void print();
+// Logs a generic message with timestamp and format as printf.
+static void log(Thread* thread, const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
+// Log exception related message
+static void log_exception(Thread* thread, const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
+static void log_deopt_message(Thread* thread, const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
+// Register default loggers
+static void init();
+};
+inline void Events::log(Thread* thread, const char* format, ...) {
+if (LogEvents) {
+va_list ap;
+va_start(ap, format);
+_messages->logv(thread, format, ap);
+va_end(ap);
+}
+}
+inline void Events::log_exception(Thread* thread, const char* format, ...) {
+if (LogEvents) {
+va_list ap;
+va_start(ap, format);
+_exceptions->logv(thread, format, ap);
+va_end(ap);
+}
+}
+inline void Events::log_deopt_message(Thread* thread, const char* format, ...) {
+if (LogEvents) {
+va_list ap;
+va_start(ap, format);
+_deopt_messages->logv(thread, format, ap);
+va_end(ap);
+}
+}
+template <class T>
+inline void EventLogBase<T>::print_log_on(outputStream* out) {
+if (ThreadLocalStorage::get_thread_slow() == NULL) {
+// Not a regular Java thread so don't bother locking
+print_log_impl(out);
+} else {
+MutexLockerEx ml(&_mutex, Mutex::_no_safepoint_check_flag);
+print_log_impl(out);
+}
+}
+// Dump the ring buffer entries that current have entries.
+template <class T>
+inline void EventLogBase<T>::print_log_impl(outputStream* out) {
+out->print_cr("%s (%d events):", _name, _count);
+if (_count == 0) {
+out->print_cr("No events");
+out->cr();
+return;
+}
+if (_count < _length) {
+for (int i = 0; i < _count; i++) {
+print(out, _records[i]);
+}
+} else {
+for (int i = _index; i < _length; i++) {
+print(out, _records[i]);
+}
+for (int i = 0; i < _index; i++) {
+print(out, _records[i]);
+}
+}
+out->cr();
+}
+// Implement a printing routine for the StringLogMessage
+template <>
+inline void EventLogBase<StringLogMessage>::print(outputStream* out, StringLogMessage& lm) {
+out->print_raw(lm);
+out->cr();
+}
+// Place markers for the beginning and end up of a set of events.
+// These end up in the default log.
+class EventMark : public StackObj {
+StringLogMessage _buffer;
+public:
+// log a begin event, format as printf
+EventMark(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
+// log an end event
+~EventMark();
+};
+#endif // SHARE_VM_UTILITIES_EVENTS_HPP

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

comparison: src/share/vm/utilities/events.hpp

src/share/vm/utilities/events.hpp