Add allocation stack traces for HPROF dump.
This feature is currently only enabled when DDMS's allocation tracking
is enabled. In the future there should be a way to enable this feature
before an application starts.
Also updates DDMS's recent allocation tracking to use a new backend
data structure that is shared with this feature.
The following system properties controls customizable parameters:
dalvik.vm.allocTrackerMax: max number of objects that have allocation
records, default 512K;
dalvik.vm.recentAllocMax: max number of records that are sent to DDMS
when clicking "Get allocation" button,
default 64K-1 (limit of the protocol);
dalvik.vm.allocStackDepth: max number of stack frames in an allocation
record, default 4.
Bug: 20037135
Change-Id: I26ed378a5613678bd3c43e846025f90470a8e059
diff --git a/runtime/gc/allocation_record.cc b/runtime/gc/allocation_record.cc
new file mode 100644
index 0000000..a385363
--- /dev/null
+++ b/runtime/gc/allocation_record.cc
@@ -0,0 +1,206 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "allocation_record.h"
+
+#include "art_method-inl.h"
+#include "base/stl_util.h"
+#include "stack.h"
+
+#ifdef HAVE_ANDROID_OS
+#include "cutils/properties.h"
+#endif
+
+namespace art {
+namespace gc {
+
+int32_t AllocRecordStackTraceElement::ComputeLineNumber() const {
+ DCHECK(method_ != nullptr);
+ return method_->GetLineNumFromDexPC(dex_pc_);
+}
+
+void AllocRecordObjectMap::SetProperties() {
+#ifdef HAVE_ANDROID_OS
+ // Check whether there's a system property overriding the max number of records.
+ const char* propertyName = "dalvik.vm.allocTrackerMax";
+ char allocMaxString[PROPERTY_VALUE_MAX];
+ if (property_get(propertyName, allocMaxString, "") > 0) {
+ char* end;
+ size_t value = strtoul(allocMaxString, &end, 10);
+ if (*end != '\0') {
+ LOG(ERROR) << "Ignoring " << propertyName << " '" << allocMaxString
+ << "' --- invalid";
+ } else {
+ alloc_record_max_ = value;
+ }
+ }
+ // Check whether there's a system property overriding the max depth of stack trace.
+ propertyName = "dalvik.vm.allocStackDepth";
+ char stackDepthString[PROPERTY_VALUE_MAX];
+ if (property_get(propertyName, stackDepthString, "") > 0) {
+ char* end;
+ size_t value = strtoul(stackDepthString, &end, 10);
+ if (*end != '\0') {
+ LOG(ERROR) << "Ignoring " << propertyName << " '" << stackDepthString
+ << "' --- invalid";
+ } else {
+ max_stack_depth_ = value;
+ }
+ }
+#endif
+}
+
+AllocRecordObjectMap::~AllocRecordObjectMap() {
+ STLDeleteValues(&entries_);
+}
+
+void AllocRecordObjectMap::SweepAllocationRecords(IsMarkedCallback* callback, void* arg) {
+ VLOG(heap) << "Start SweepAllocationRecords()";
+ size_t count_deleted = 0, count_moved = 0;
+ for (auto it = entries_.begin(), end = entries_.end(); it != end;) {
+ // This does not need a read barrier because this is called by GC.
+ mirror::Object* old_object = it->first.Read<kWithoutReadBarrier>();
+ AllocRecord* record = it->second;
+ mirror::Object* new_object = callback(old_object, arg);
+ if (new_object == nullptr) {
+ delete record;
+ it = entries_.erase(it);
+ ++count_deleted;
+ } else {
+ if (old_object != new_object) {
+ it->first = GcRoot<mirror::Object>(new_object);
+ ++count_moved;
+ }
+ ++it;
+ }
+ }
+ VLOG(heap) << "Deleted " << count_deleted << " allocation records";
+ VLOG(heap) << "Updated " << count_moved << " allocation records";
+}
+
+struct AllocRecordStackVisitor : public StackVisitor {
+ AllocRecordStackVisitor(Thread* thread, AllocRecordStackTrace* trace_in, size_t max)
+ SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
+ : StackVisitor(thread, nullptr, StackVisitor::StackWalkKind::kIncludeInlinedFrames),
+ trace(trace_in),
+ depth(0),
+ max_depth(max) {}
+
+ // TODO: Enable annotalysis. We know lock is held in constructor, but abstraction confuses
+ // annotalysis.
+ bool VisitFrame() OVERRIDE NO_THREAD_SAFETY_ANALYSIS {
+ if (depth >= max_depth) {
+ return false;
+ }
+ ArtMethod* m = GetMethod();
+ if (!m->IsRuntimeMethod()) {
+ trace->SetStackElementAt(depth, m, GetDexPc());
+ ++depth;
+ }
+ return true;
+ }
+
+ ~AllocRecordStackVisitor() {
+ trace->SetDepth(depth);
+ }
+
+ AllocRecordStackTrace* trace;
+ size_t depth;
+ const size_t max_depth;
+};
+
+void AllocRecordObjectMap::SetAllocTrackingEnabled(bool enable) {
+ Thread* self = Thread::Current();
+ Heap* heap = Runtime::Current()->GetHeap();
+ if (enable) {
+ {
+ MutexLock mu(self, *Locks::alloc_tracker_lock_);
+ if (heap->IsAllocTrackingEnabled()) {
+ return; // Already enabled, bail.
+ }
+ AllocRecordObjectMap* records = new AllocRecordObjectMap();
+ CHECK(records != nullptr);
+ records->SetProperties();
+ std::string self_name;
+ self->GetThreadName(self_name);
+ if (self_name == "JDWP") {
+ records->alloc_ddm_thread_id_ = self->GetTid();
+ }
+ size_t sz = sizeof(AllocRecordStackTraceElement) * records->max_stack_depth_ +
+ sizeof(AllocRecord) + sizeof(AllocRecordStackTrace);
+ LOG(INFO) << "Enabling alloc tracker (" << records->alloc_record_max_ << " entries of "
+ << records->max_stack_depth_ << " frames, taking up to "
+ << PrettySize(sz * records->alloc_record_max_) << ")";
+ heap->SetAllocationRecords(records);
+ heap->SetAllocTrackingEnabled(true);
+ }
+ Runtime::Current()->GetInstrumentation()->InstrumentQuickAllocEntryPoints();
+ } else {
+ {
+ MutexLock mu(self, *Locks::alloc_tracker_lock_);
+ if (!heap->IsAllocTrackingEnabled()) {
+ return; // Already disabled, bail.
+ }
+ heap->SetAllocTrackingEnabled(false);
+ LOG(INFO) << "Disabling alloc tracker";
+ heap->SetAllocationRecords(nullptr);
+ }
+ // If an allocation comes in before we uninstrument, we will safely drop it on the floor.
+ Runtime::Current()->GetInstrumentation()->UninstrumentQuickAllocEntryPoints();
+ }
+}
+
+void AllocRecordObjectMap::RecordAllocation(Thread* self, mirror::Object* obj, size_t byte_count) {
+ MutexLock mu(self, *Locks::alloc_tracker_lock_);
+ Heap* heap = Runtime::Current()->GetHeap();
+ if (!heap->IsAllocTrackingEnabled()) {
+ // In the process of shutting down recording, bail.
+ return;
+ }
+
+ AllocRecordObjectMap* records = heap->GetAllocationRecords();
+ DCHECK(records != nullptr);
+
+ // Do not record for DDM thread
+ if (records->alloc_ddm_thread_id_ == self->GetTid()) {
+ return;
+ }
+
+ DCHECK_LE(records->Size(), records->alloc_record_max_);
+
+ // Remove oldest record.
+ if (records->Size() == records->alloc_record_max_) {
+ records->RemoveOldest();
+ }
+
+ // Get stack trace.
+ const size_t max_depth = records->max_stack_depth_;
+ AllocRecordStackTrace* trace = new AllocRecordStackTrace(self->GetTid(), max_depth);
+ // add scope to make "visitor" destroyed promptly, in order to set the trace->depth_
+ {
+ AllocRecordStackVisitor visitor(self, trace, max_depth);
+ visitor.WalkStack();
+ }
+
+ // Fill in the basics.
+ AllocRecord* record = new AllocRecord(byte_count, trace);
+
+ records->Put(obj, record);
+ DCHECK_LE(records->Size(), records->alloc_record_max_);
+}
+
+} // namespace gc
+} // namespace art