/*

 * Copyright (c) 2011, 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

 * 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 "jfr/metadata/jfrSerializer.hpp"

#include "jfr/recorder/checkpoint/types/traceid/jfrTraceId.inline.hpp"

#include "jfr/recorder/repository/jfrChunkWriter.hpp"

#include "jfr/recorder/service/jfrOptionSet.hpp"

#include "jfr/recorder/stacktrace/jfrStackTraceRepository.hpp"

#include "jfr/utilities/jfrTypes.hpp"

#include "memory/allocation.inline.hpp"

#include "runtime/mutexLocker.hpp"

#include "runtime/os.inline.hpp"

#include "runtime/safepoint.hpp"

#include "runtime/task.hpp"

#include "runtime/vframe.inline.hpp"

class vframeStreamSamples : public vframeStreamCommon {

 public:

  // constructor that starts with sender of frame fr (top_frame)

  vframeStreamSamples(JavaThread *jt, frame fr, bool stop_at_java_call_stub);

  void samples_next();

  void stop() {}

};

vframeStreamSamples::vframeStreamSamples(JavaThread *jt, frame fr, bool stop_at_java_call_stub) : vframeStreamCommon(jt) {

  _stop_at_java_call_stub = stop_at_java_call_stub;

  _frame = fr;

  // We must always have a valid frame to start filling

  bool filled_in = fill_from_frame();

  assert(filled_in, "invariant");

}

// Solaris SPARC Compiler1 needs an additional check on the grandparent

// of the top_frame when the parent of the top_frame is interpreted and

// the grandparent is compiled. However, in this method we do not know

// the relationship of the current _frame relative to the top_frame so

// we implement a more broad sanity check. When the previous callee is

// interpreted and the current sender is compiled, we verify that the

// current sender is also walkable. If it is not walkable, then we mark

// the current vframeStream as at the end.

void vframeStreamSamples::samples_next() {

  // handle frames with inlining

  if (_mode == compiled_mode &&

      vframeStreamCommon::fill_in_compiled_inlined_sender()) {

    return;

  }

  // handle general case

  u4 loop_count = 0;

  u4 loop_max = MAX_STACK_DEPTH * 2;

  do {

    loop_count++;

    // By the time we get here we should never see unsafe but better safe then segv'd

    if (loop_count > loop_max || !_frame.safe_for_sender(_thread)) {

      _mode = at_end_mode;

      return;

    }

    _frame = _frame.sender(&_reg_map);

  } while (!fill_from_frame());

}

static JfrStackTraceRepository* _instance = NULL;

JfrStackTraceRepository& JfrStackTraceRepository::instance() {

  return *_instance;

}

JfrStackTraceRepository* JfrStackTraceRepository::create() {

  assert(_instance == NULL, "invariant");

  _instance = new JfrStackTraceRepository();

  return _instance;

}

void JfrStackTraceRepository::destroy() {

  assert(_instance != NULL, "invarinat");

  delete _instance;

  _instance = NULL;

}

JfrStackTraceRepository::JfrStackTraceRepository() : _next_id(0), _entries(0) {

  memset(_table, 0, sizeof(_table));

}

class JfrFrameType : public JfrSerializer {

 public:

  void serialize(JfrCheckpointWriter& writer) {

    writer.write_count(JfrStackFrame::NUM_FRAME_TYPES);

    writer.write_key(JfrStackFrame::FRAME_INTERPRETER);

    writer.write("Interpreted");

    writer.write_key(JfrStackFrame::FRAME_JIT);

    writer.write("JIT compiled");

    writer.write_key(JfrStackFrame::FRAME_INLINE);

    writer.write("Inlined");

    writer.write_key(JfrStackFrame::FRAME_NATIVE);

    writer.write("Native");

  }

};

bool JfrStackTraceRepository::initialize() {

}

size_t JfrStackTraceRepository::clear() {

  MutexLocker lock(JfrStacktrace_lock, Mutex::_no_safepoint_check_flag);

  if (_entries == 0) {

    return 0;

  }

  for (u4 i = 0; i < TABLE_SIZE; ++i) {

    JfrStackTraceRepository::StackTrace* stacktrace = _table[i];

    while (stacktrace != NULL) {

      JfrStackTraceRepository::StackTrace* next = stacktrace->next();

      delete stacktrace;

      stacktrace = next;

    }

  }

  memset(_table, 0, sizeof(_table));

  const size_t processed = _entries;

  _entries = 0;

  return processed;

}

traceid JfrStackTraceRepository::add_trace(const JfrStackTrace& stacktrace) {

  MutexLocker lock(JfrStacktrace_lock, Mutex::_no_safepoint_check_flag);

  const size_t index = stacktrace._hash % TABLE_SIZE;

  const StackTrace* table_entry = _table[index];

  while (table_entry != NULL) {

    if (table_entry->equals(stacktrace)) {

      return table_entry->id();

    }

    table_entry = table_entry->next();

  }

  if (!stacktrace.have_lineno()) {

    return 0;

  }

  traceid id = ++_next_id;

  _table[index] = new StackTrace(id, stacktrace, _table[index]);

  ++_entries;

  return id;

}

traceid JfrStackTraceRepository::add(const JfrStackTrace& stacktrace) {

  return instance().add_trace(stacktrace);

}

traceid JfrStackTraceRepository::record(Thread* thread, int skip /* 0 */) {

  assert(thread == Thread::current(), "invariant");

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

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

  if (tl->has_cached_stack_trace()) {

    return tl->cached_stack_trace_id();

  }

  if (!thread->is_Java_thread() || thread->is_hidden_from_external_view()) {

    return 0;

  }

  JfrStackFrame* frames = tl->stackframes();

  if (frames == NULL) {

    // pending oom

    return 0;

  }

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

  assert(tl->stackframes() == frames, "invariant");

  return instance().record_for((JavaThread*)thread, skip,frames, tl->stackdepth());

}

traceid JfrStackTraceRepository::record(Thread* thread, int skip, unsigned int* hash) {

  assert(thread == Thread::current(), "invariant");

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

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

  if (tl->has_cached_stack_trace()) {

    *hash = tl->cached_stack_trace_hash();

    return tl->cached_stack_trace_id();

  }

    return 0;

  }

  JfrStackFrame* frames = tl->stackframes();

  if (frames == NULL) {

    // pending oom

    return 0;

  }

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

  assert(tl->stackframes() == frames, "invariant");

  return instance().record_for((JavaThread*)thread, skip, frames, tl->stackdepth(), hash);

}

traceid JfrStackTraceRepository::record_for(JavaThread* thread, int skip, JfrStackFrame *frames, u4 max_frames) {

  JfrStackTrace stacktrace(frames, max_frames);

  if (!stacktrace.record_safe(thread, skip)) {

    return 0;

  }

  traceid tid = add(stacktrace);

  if (tid == 0) {

    stacktrace.resolve_linenos();

    tid = add(stacktrace);

  }

  return tid;

}

traceid JfrStackTraceRepository::record_for(JavaThread* thread, int skip, JfrStackFrame *frames, u4 max_frames, unsigned int* hash) {

  assert(hash != NULL && *hash == 0, "invariant");

  JfrStackTrace stacktrace(frames, max_frames);

  if (!stacktrace.record_safe(thread, skip, true)) {

    return 0;

  }

  traceid tid = add(stacktrace);

  if (tid == 0) {

    stacktrace.resolve_linenos();

    tid = add(stacktrace);

  }

  *hash = stacktrace._hash;

  return tid;

}

size_t JfrStackTraceRepository::write_impl(JfrChunkWriter& sw, bool clear) {

  MutexLocker lock(JfrStacktrace_lock, Mutex::_no_safepoint_check_flag);

  assert(_entries > 0, "invariant");

  int count = 0;

  for (u4 i = 0; i < TABLE_SIZE; ++i) {

    JfrStackTraceRepository::StackTrace* stacktrace = _table[i];

    while (stacktrace != NULL) {

      JfrStackTraceRepository::StackTrace* next = stacktrace->next();

      if (stacktrace->should_write()) {

        stacktrace->write(sw);

        ++count;

      }

      if (clear) {

        delete stacktrace;

      }

      stacktrace = next;

    }

  }

  if (clear) {

    memset(_table, 0, sizeof(_table));

    _entries = 0;

  }

  return count;

}

size_t JfrStackTraceRepository::write(JfrChunkWriter& sw, bool clear) {

  return _entries > 0 ? write_impl(sw, clear) : 0;

}

traceid JfrStackTraceRepository::write(JfrCheckpointWriter& writer, traceid id, unsigned int hash) {

  assert(JfrStacktrace_lock->owned_by_self(), "invariant");

  const StackTrace* const trace = resolve_entry(hash, id);

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

  assert(trace->hash() == hash, "invariant");

  assert(trace->id() == id, "invariant");

  trace->write(writer);

  return id;

}

JfrStackTraceRepository::StackTrace::StackTrace(traceid id, const JfrStackTrace& trace, JfrStackTraceRepository::StackTrace* next) :

  _next(next),

  _frames(NULL),

  _id(id),

  _nr_of_frames(trace._nr_of_frames),

  _hash(trace._hash),

  _reached_root(trace._reached_root),

  _written(false) {

  if (_nr_of_frames > 0) {

    _frames = NEW_C_HEAP_ARRAY(JfrStackFrame, _nr_of_frames, mtTracing);

    memcpy(_frames, trace._frames, _nr_of_frames * sizeof(JfrStackFrame));

  }

}

JfrStackTraceRepository::StackTrace::~StackTrace() {

  if (_frames != NULL) {

    FREE_C_HEAP_ARRAY(JfrStackFrame, _frames);

  }

}

bool JfrStackTraceRepository::StackTrace::equals(const JfrStackTrace& rhs) const {

  if (_reached_root != rhs._reached_root || _nr_of_frames != rhs._nr_of_frames || _hash != rhs._hash) {

    return false;

  }

  for (u4 i = 0; i < _nr_of_frames; ++i) {

    if (!_frames[i].equals(rhs._frames[i])) {

      return false;

    }

  }

  return true;

}

template <typename Writer>

static void write_stacktrace(Writer& w, traceid id, bool reached_root, u4 nr_of_frames, const JfrStackFrame* frames) {

  w.write((u8)id);

  w.write((u1)!reached_root);

  w.write(nr_of_frames);

  for (u4 i = 0; i < nr_of_frames; ++i) {

    frames[i].write(w);

  }

}

void JfrStackTraceRepository::StackTrace::write(JfrChunkWriter& sw) const {

  assert(!_written, "invariant");

  write_stacktrace(sw, _id, _reached_root, _nr_of_frames, _frames);

  _written = true;

}

void JfrStackTraceRepository::StackTrace::write(JfrCheckpointWriter& cpw) const {

  write_stacktrace(cpw, _id, _reached_root, _nr_of_frames, _frames);

}

// JfrStackFrame

bool JfrStackFrame::equals(const JfrStackFrame& rhs) const {

  return _methodid == rhs._methodid && _bci == rhs._bci && _type == rhs._type;

}

template <typename Writer>

static void write_frame(Writer& w, traceid methodid, int line, int bci, u1 type) {

  w.write((u8)methodid);

  w.write((u4)line);

  w.write((u4)bci);

  w.write((u8)type);

}

void JfrStackFrame::write(JfrChunkWriter& cw) const {

  write_frame(cw, _methodid, _line, _bci, _type);

}

void JfrStackFrame::write(JfrCheckpointWriter& cpw) const {

  write_frame(cpw, _methodid, _line, _bci, _type);

}

// invariant is that the entry to be resolved actually exists in the table

const JfrStackTraceRepository::StackTrace* JfrStackTraceRepository::resolve_entry(unsigned int hash, traceid id) const {

  const size_t index = (hash % TABLE_SIZE);

  const StackTrace* trace = _table[index];

  while (trace != NULL && trace->id() != id) {

    trace = trace->next();

  }

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

  assert(trace->hash() == hash, "invariant");

  assert(trace->id() == id, "invariant");

  return trace;

}

void JfrStackFrame::resolve_lineno() {

  assert(_method, "no method pointer");

  assert(_line == 0, "already have linenumber");

  _line = _method->line_number_from_bci(_bci);

}

void JfrStackTrace::set_frame(u4 frame_pos, JfrStackFrame& frame) {

  assert(frame_pos < _max_frames, "illegal frame_pos");

  _frames[frame_pos] = frame;

}

void JfrStackTrace::resolve_linenos() {

  for(unsigned int i = 0; i < _nr_of_frames; i++) {

    _frames[i].resolve_lineno();

  }

  _lineno = true;

}

bool JfrStackTrace::record_safe(JavaThread* thread, int skip, bool leakp /* false */) {

  assert(thread == Thread::current(), "Thread stack needs to be walkable");

  vframeStream vfs(thread);

  u4 count = 0;

  _reached_root = true;

  for(int i = 0; i < skip; i++) {

    if (vfs.at_end()) {

      break;

    }

    vfs.next();

  }

  while (!vfs.at_end()) {

    if (count >= _max_frames) {

      _reached_root = false;

      break;

    }

    const Method* method = vfs.method();

    const traceid mid = JfrTraceId::use(method, leakp);

    int type = vfs.is_interpreted_frame() ? JfrStackFrame::FRAME_INTERPRETER : JfrStackFrame::FRAME_JIT;

    int bci = 0;

    if (method->is_native()) {

      type = JfrStackFrame::FRAME_NATIVE;

    } else {

      bci = vfs.bci();

    }

    // Can we determine if it's inlined?

    _hash = (_hash << 2) + (unsigned int)(((size_t)mid >> 2) + (bci << 4) + type);

    _frames[count] = JfrStackFrame(mid, bci, type, method);

    vfs.next();

    count++;

  }

  _nr_of_frames = count;

  return true;

}

bool JfrStackTrace::record_thread(JavaThread& thread, frame& frame) {

  vframeStreamSamples st(&thread, frame, false);

  u4 count = 0;

  _reached_root = true;

  while (!st.at_end()) {

    if (count >= _max_frames) {

      _reached_root = false;

      break;

    }

    const Method* method = st.method();

    if (!Method::is_valid_method(method)) {

      // we throw away everything we've gathered in this sample since

      // none of it is safe

      return false;

    }

    const traceid mid = JfrTraceId::use(method);

    int type = st.is_interpreted_frame() ? JfrStackFrame::FRAME_INTERPRETER : JfrStackFrame::FRAME_JIT;

    int bci = 0;

    if (method->is_native()) {

      type = JfrStackFrame::FRAME_NATIVE;

    } else {

      bci = st.bci();

    }

    const int lineno = method->line_number_from_bci(bci);

    // Can we determine if it's inlined?

    _hash = (_hash << 2) + (unsigned int)(((size_t)mid >> 2) + (bci << 4) + type);

    st.samples_next();

    count++;

  }

  _lineno = true;

  _nr_of_frames = count;

  return true;

}

void JfrStackTraceRepository::write_metadata(JfrCheckpointWriter& writer) {

  JfrFrameType fct;

  writer.write_type(TYPE_FRAMETYPE);

  fct.serialize(writer);

}