--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/share/vm/services/memSnapshot.cpp	Thu Jun 28 17:03:16 2012 -0400
@@ -0,0 +1,463 @@
+/*
+ * 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