/*

 * Copyright (c) 2012, 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 "runtime/mutexLocker.hpp"

#include "utilities/decoder.hpp"

#include "services/memBaseline.hpp"

#include "services/memPtr.hpp"

#include "services/memPtrArray.hpp"

#include "services/memSnapshot.hpp"

#include "services/memTracker.hpp"

// stagging data groups the data of a VM memory range, so we can consolidate

// them into one record during the walk

bool StagingWalker::consolidate_vm_records(VMMemRegionEx* vm_rec) {

  MemPointerRecord* cur = (MemPointerRecord*)_itr.current();

  assert(cur != NULL && cur->is_vm_pointer(), "not a virtual memory pointer");

  jint cur_seq;

  jint next_seq;

  bool trackCallsite = MemTracker::track_callsite();

  if (trackCallsite) {

    vm_rec->init((MemPointerRecordEx*)cur);

    cur_seq = ((SeqMemPointerRecordEx*)cur)->seq();

  } else {

    vm_rec->init((MemPointerRecord*)cur);

    cur_seq = ((SeqMemPointerRecord*)cur)->seq();

  }

  // only can consolidate when we have allocation record,

  // which contains virtual memory range

  if (!cur->is_allocation_record()) {

    _itr.next();

    return true;

  }

  // allocation range

  address base = cur->addr();

  address end = base + cur->size();

  MemPointerRecord* next = (MemPointerRecord*)_itr.peek_next();

  // if the memory range is alive

  bool live_vm_rec = true;

  while (next != NULL && next->is_vm_pointer()) {

    if (next->is_allocation_record()) {

      assert(next->addr() >= base, "sorting order or overlapping");

      break;

    }

    if (trackCallsite) {

      next_seq = ((SeqMemPointerRecordEx*)next)->seq();

    } else {

      next_seq = ((SeqMemPointerRecord*)next)->seq();

    }

    if (next_seq < cur_seq) {

      _itr.next();

      next = (MemPointerRecord*)_itr.peek_next();

      continue;

    }

    if (next->is_deallocation_record()) {

      if (next->addr() == base && next->size() == cur->size()) {

        // the virtual memory range has been released

        _itr.next();

        live_vm_rec = false;

        break;

      } else if (next->addr() < end) { // partial release

        vm_rec->partial_release(next->addr(), next->size());

        _itr.next();

      } else {

        break;

      }

    } else if (next->is_commit_record()) {

      if (next->addr() >= base && next->addr() + next->size() <= end) {

        vm_rec->commit(next->size());

        _itr.next();

      } else {

        assert(next->addr() >= base, "sorting order or overlapping");

        break;

      }

    } else if (next->is_uncommit_record()) {

      if (next->addr() >= base && next->addr() + next->size() <= end) {

        vm_rec->uncommit(next->size());

        _itr.next();

      } else {

        assert(next->addr() >= end, "sorting order or overlapping");

        break;

      }

    } else if (next->is_type_tagging_record()) {

      if (next->addr() >= base && next->addr() < end ) {

        vm_rec->tag(next->flags());

        _itr.next();

      } else {

          break;

      }

    } else {

      assert(false, "unknown record type");

    }

    next = (MemPointerRecord*)_itr.peek_next();

  }

  _itr.next();

  return live_vm_rec;

}

MemPointer* StagingWalker::next() {

  MemPointerRecord* cur_p = (MemPointerRecord*)_itr.current();

  if (cur_p == NULL) {

    _end_of_array = true;

    return NULL;

  }

  MemPointerRecord* next_p;

  if (cur_p->is_vm_pointer()) {

    _is_vm_record = true;

    if (!consolidate_vm_records(&_vm_record)) {

      return next();

    }

  } else { // malloc-ed pointer

    _is_vm_record = false;

    next_p = (MemPointerRecord*)_itr.peek_next();

    if (next_p != NULL && next_p->addr() == cur_p->addr()) {

      assert(cur_p->is_allocation_record(), "sorting order");

      assert(!next_p->is_allocation_record(), "sorting order");

      _itr.next();

      if (cur_p->seq() < next_p->seq()) {

        cur_p = next_p;

      }

    }

    if (MemTracker::track_callsite()) {

      _malloc_record.init((MemPointerRecordEx*)cur_p);

    } else {

      _malloc_record.init((MemPointerRecord*)cur_p);

    }

    _itr.next();

  }

  return current();

}

MemSnapshot::MemSnapshot() {

  if (MemTracker::track_callsite()) {

    _alloc_ptrs = new (std::nothrow) MemPointerArrayImpl<MemPointerRecordEx>();

    _vm_ptrs = new (std::nothrow)MemPointerArrayImpl<VMMemRegionEx>(64, true);

    _staging_area = new (std::nothrow)MemPointerArrayImpl<SeqMemPointerRecordEx>();

  } else {

    _alloc_ptrs = new (std::nothrow) MemPointerArrayImpl<MemPointerRecord>();

    _vm_ptrs = new (std::nothrow)MemPointerArrayImpl<VMMemRegion>(64, true);

    _staging_area = new (std::nothrow)MemPointerArrayImpl<SeqMemPointerRecord>();

  }

  _lock = new (std::nothrow) Mutex(Monitor::native, "memSnapshotLock");

  NOT_PRODUCT(_untracked_count = 0;)

}

MemSnapshot::~MemSnapshot() {

  assert(MemTracker::shutdown_in_progress(), "native memory tracking still on");

  {

    MutexLockerEx locker(_lock);

    if (_staging_area != NULL) {

      delete _staging_area;

      _staging_area = NULL;

    }

    if (_alloc_ptrs != NULL) {

      delete _alloc_ptrs;

      _alloc_ptrs = NULL;

    }

    if (_vm_ptrs != NULL) {

      delete _vm_ptrs;

      _vm_ptrs = NULL;

    }

  }

  if (_lock != NULL) {

    delete _lock;

    _lock = NULL;

  }

}

void MemSnapshot::copy_pointer(MemPointerRecord* dest, const MemPointerRecord* src) {

  assert(dest != NULL && src != NULL, "Just check");

  assert(dest->addr() == src->addr(), "Just check");

  MEMFLAGS flags = dest->flags();

  if (MemTracker::track_callsite()) {

    *(MemPointerRecordEx*)dest = *(MemPointerRecordEx*)src;

  } else {

    *dest = *src;

  }

}

// merge a per-thread memory recorder to the staging area

bool MemSnapshot::merge(MemRecorder* rec) {

  assert(rec != NULL && !rec->out_of_memory(), "Just check");

  // out of memory

  if (_staging_area == NULL || _staging_area->out_of_memory()) {

    return false;

  }

  SequencedRecordIterator itr(rec->pointer_itr());

  MutexLockerEx lock(_lock, true);

  MemPointerIterator staging_itr(_staging_area);

  MemPointerRecord *p1, *p2;

  p1 = (MemPointerRecord*) itr.current();

  while (p1 != NULL) {

    p2 = (MemPointerRecord*)staging_itr.locate(p1->addr());

    // we have not seen this memory block, so just add to staging area

    if (p2 == NULL) {

      if (!staging_itr.insert(p1)) {

        return false;

      }

    } else if (p1->addr() == p2->addr()) {

      MemPointerRecord* staging_next = (MemPointerRecord*)staging_itr.peek_next();

      // a memory block can have many tagging records, find right one to replace or

      // right position to insert

      while (staging_next != NULL && staging_next->addr() == p1->addr()) {

        if ((staging_next->flags() & MemPointerRecord::tag_masks) <=

          (p1->flags() & MemPointerRecord::tag_masks)) {

          p2 = (MemPointerRecord*)staging_itr.next();

          staging_next = (MemPointerRecord*)staging_itr.peek_next();

        } else {

          break;

        }

      }

      int df = (p1->flags() & MemPointerRecord::tag_masks) -

        (p2->flags() & MemPointerRecord::tag_masks);

      if (df == 0) {

        assert(p1->seq() > 0, "not sequenced");

        assert(p2->seq() > 0, "not sequenced");

        if (p1->seq() > p2->seq()) {

          copy_pointer(p2, p1);

        }

      } else if (df < 0) {

        if (!staging_itr.insert(p1)) {

          return false;

        }

      } else {

        if (!staging_itr.insert_after(p1)) {

          return false;

        }

      }

    } else if (p1->addr() < p2->addr()) {

      if (!staging_itr.insert(p1)) {

        return false;

      }

    } else {

      if (!staging_itr.insert_after(p1)) {

        return false;

      }

    }

    p1 = (MemPointerRecord*)itr.next();

  }

  NOT_PRODUCT(void check_staging_data();)

  return true;

}

// promote data to next generation

void MemSnapshot::promote() {

  assert(_alloc_ptrs != NULL && _staging_area != NULL && _vm_ptrs != NULL,

    "Just check");

  MutexLockerEx lock(_lock, true);

  StagingWalker walker(_staging_area);

  MemPointerIterator malloc_itr(_alloc_ptrs);

  VMMemPointerIterator vm_itr(_vm_ptrs);

  MemPointer* cur = walker.current();

  while (cur != NULL) {

    if (walker.is_vm_record()) {

      VMMemRegion* cur_vm = (VMMemRegion*)cur;

      VMMemRegion* p = (VMMemRegion*)vm_itr.locate(cur_vm->addr());

      cur_vm = (VMMemRegion*)cur;

      if (p != NULL && (p->contains(cur_vm) || p->base() == cur_vm->base())) {

        assert(p->is_reserve_record() ||

          p->is_commit_record(), "wrong vm record type");

        // resize existing reserved range

        if (cur_vm->is_reserve_record() && p->base() == cur_vm->base()) {

          assert(cur_vm->size() >= p->committed_size(), "incorrect resizing");

          p->set_reserved_size(cur_vm->size());

        } else if (cur_vm->is_commit_record()) {

          p->commit(cur_vm->committed_size());

        } else if (cur_vm->is_uncommit_record()) {

          p->uncommit(cur_vm->committed_size());

          if (!p->is_reserve_record() && p->committed_size() == 0) {

            vm_itr.remove();

          }

        } else if (cur_vm->is_type_tagging_record()) {

          p->tag(cur_vm->flags());

        } else if (cur_vm->is_release_record()) {

          if (cur_vm->base() == p->base() && cur_vm->size() == p->size()) {

            // release the whole range

            vm_itr.remove();

          } else {

            // partial release

            p->partial_release(cur_vm->base(), cur_vm->size());

          }

        } else {

          // we do see multiple reserver on the same vm range

          assert((cur_vm->is_commit_record() || cur_vm->is_reserve_record()) &&

             cur_vm->base() == p->base() && cur_vm->size() == p->size(), "bad record");

          p->tag(cur_vm->flags());

        }

      } else {

        if(cur_vm->is_reserve_record()) {

          if (p == NULL || p->base() > cur_vm->base()) {

            vm_itr.insert(cur_vm);

          } else {

            vm_itr.insert_after(cur_vm);

          }

        } else {

#ifdef ASSERT

          // In theory, we should assert without conditions. However, in case of native

          // thread stack, NMT explicitly releases the thread stack in Thread's destructor,

          // due to platform dependent behaviors. On some platforms, we see uncommit/release

          // native thread stack, but some, we don't.

          if (!cur_vm->is_uncommit_record() && !cur_vm->is_deallocation_record()) {

            ShouldNotReachHere();

          }

#endif

        }

      }

    } else {

      MemPointerRecord* cur_p = (MemPointerRecord*)cur;

      MemPointerRecord* p = (MemPointerRecord*)malloc_itr.locate(cur->addr());

      if (p != NULL && cur_p->addr() == p->addr()) {

        assert(p->is_allocation_record() || p->is_arena_size_record(), "untracked");

        if (cur_p->is_allocation_record() || cur_p->is_arena_size_record()) {

          copy_pointer(p, cur_p);

        } else {   // deallocation record

          assert(cur_p->is_deallocation_record(), "wrong record type");

          // we are removing an arena record, we also need to remove its 'size'

          // record behind it

          if (p->is_arena_record()) {

            MemPointerRecord* next_p = (MemPointerRecord*)malloc_itr.peek_next();

            if (next_p->is_arena_size_record()) {

              assert(next_p->is_size_record_of_arena(p), "arena records dont match");

              malloc_itr.remove();

            }

          }

          malloc_itr.remove();

        }

      } else {

        if (cur_p->is_arena_size_record()) {

          MemPointerRecord* prev_p = (MemPointerRecord*)malloc_itr.peek_prev();

          if (prev_p != NULL &&

             (!prev_p->is_arena_record() || !cur_p->is_size_record_of_arena(prev_p))) {

            // arena already deallocated

            cur_p = NULL;

          }

        }

        if (cur_p != NULL) {

          if (cur_p->is_allocation_record() || cur_p->is_arena_size_record()) {

            if (p != NULL && cur_p->addr() > p->addr()) {

              malloc_itr.insert_after(cur);

            } else {

              malloc_itr.insert(cur);

            }

          }

#ifndef PRODUCT

          else if (!has_allocation_record(cur_p->addr())){

            // NMT can not track some startup memory, which allocated before NMT

            // is enabled

            _untracked_count ++;

          }

#endif

        }

      }

    }

    cur = walker.next();

  }

  NOT_PRODUCT(check_malloc_pointers();)

  _staging_area->shrink();

  _staging_area->clear();

}

#ifdef ASSERT

void MemSnapshot::print_snapshot_stats(outputStream* st) {

  st->print_cr("Snapshot:");

  st->print_cr("\tMalloced: %d/%d [%5.2f%%]  %dKB", _alloc_ptrs->length(), _alloc_ptrs->capacity(),

    (100.0 * (float)_alloc_ptrs->length()) / (float)_alloc_ptrs->capacity(), _alloc_ptrs->instance_size()/K);

  st->print_cr("\tVM: %d/%d [%5.2f%%] %dKB", _vm_ptrs->length(), _vm_ptrs->capacity(),

    (100.0 * (float)_vm_ptrs->length()) / (float)_vm_ptrs->capacity(), _vm_ptrs->instance_size()/K);

  st->print_cr("\tStaging:     %d/%d [%5.2f%%] %dKB", _staging_area->length(), _staging_area->capacity(),

    (100.0 * (float)_staging_area->length()) / (float)_staging_area->capacity(), _staging_area->instance_size()/K);

  st->print_cr("\tUntracked allocation: %d", _untracked_count);

}

void MemSnapshot::check_malloc_pointers() {

  MemPointerArrayIteratorImpl mItr(_alloc_ptrs);

  MemPointerRecord* p = (MemPointerRecord*)mItr.current();

  MemPointerRecord* prev = NULL;

  while (p != NULL) {

    if (prev != NULL) {

      assert(p->addr() >= prev->addr(), "sorting order");

    }

    prev = p;

    p = (MemPointerRecord*)mItr.next();

  }

}

void MemSnapshot::check_staging_data() {

  MemPointerArrayIteratorImpl itr(_staging_area);

  MemPointerRecord* cur = (MemPointerRecord*)itr.current();

  MemPointerRecord* next = (MemPointerRecord*)itr.next();

  while (next != NULL) {

    assert((next->addr() > cur->addr()) ||

      ((next->flags() & MemPointerRecord::tag_masks) >

       (cur->flags() & MemPointerRecord::tag_masks)),

       "sorting order");

    cur = next;

    next = (MemPointerRecord*)itr.next();

  }

}

bool MemSnapshot::has_allocation_record(address addr) {

  MemPointerArrayIteratorImpl itr(_staging_area);

  MemPointerRecord* cur = (MemPointerRecord*)itr.current();

  while (cur != NULL) {

    if (cur->addr() == addr && cur->is_allocation_record()) {

      return true;

    }

    cur = (MemPointerRecord*)itr.next();

  }

  return false;

}

#endif