src/trace_processor/heap_profile_tracker.cc - third_party/perfetto - Git at Google

 /*
  * Copyright (C) 2019 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 "src/trace_processor/heap_profile_tracker.h"

 #include "src/trace_processor/process_tracker.h"
 #include "src/trace_processor/trace_processor_context.h"

 #include "perfetto/base/logging.h"

 namespace perfetto {
 namespace trace_processor {
 namespace {

 std::string ToHex(const char* build_id, size_t size) {
   std::string hex_build_id(2 * size + 1, 'x');
   for (size_t i = 0; i < size; ++i) {
     // snprintf prints 3 characters, the two hex digits and a null byte. As we
     // write left to write, we keep overwriting the nullbytes, except for the
     // last call to snprintf.
     snprintf(&(hex_build_id[2 * i]), 3, "%02hhx", build_id[i]);
   }
   // Remove the trailing nullbyte produced by the last snprintf.
   hex_build_id.resize(2 * size);
   return hex_build_id;
 }

 }  // namespace

 HeapProfileTracker::InternLookup::~InternLookup() = default;

 HeapProfileTracker::HeapProfileTracker(TraceProcessorContext* context)
     : context_(context), empty_(context_->storage->InternString({"", 0})) {}

 HeapProfileTracker::~HeapProfileTracker() = default;

 void HeapProfileTracker::AddString(SourceStringId id, StringId str) {
   string_map_.emplace(id, str);
 }

 int64_t HeapProfileTracker::AddMapping(SourceMappingId id,
                                        const SourceMapping& mapping,
                                        const InternLookup* intern_lookup) {
   auto opt_name_id = FindString(mapping.name_id, intern_lookup);
   if (!opt_name_id) {
     context_->storage->IncrementStats(stats::heapprofd_invalid_string_id);
     PERFETTO_DFATAL("Invalid string.");
     return -1;
   }
   const StringId name_id = opt_name_id.value();

   auto opt_build_id = FindString(mapping.build_id, intern_lookup);
   if (!opt_build_id) {
     context_->storage->IncrementStats(stats::heapprofd_invalid_string_id);
     PERFETTO_DFATAL("Invalid string.");
     return -1;
   }
   const StringId raw_build_id = opt_build_id.value();
   NullTermStringView raw_build_id_str =
       context_->storage->GetString(raw_build_id);
   StringId build_id = empty_;
   if (raw_build_id_str.size() > 0) {
     std::string hex_build_id =
         ToHex(raw_build_id_str.c_str(), raw_build_id_str.size());
     build_id = context_->storage->InternString(base::StringView(hex_build_id));
   }

   TraceStorage::HeapProfileMappings::Row row{
       build_id,
       static_cast<int64_t>(mapping.exact_offset),
       static_cast<int64_t>(mapping.start_offset),
       static_cast<int64_t>(mapping.start),
       static_cast<int64_t>(mapping.end),
       static_cast<int64_t>(mapping.load_bias),
       name_id};

   int64_t cur_row;
   auto it = mapping_idx_.find(row);
   if (it != mapping_idx_.end()) {
     cur_row = it->second;
   } else {
     cur_row = context_->storage->mutable_heap_profile_mappings()->Insert(row);
     mapping_idx_.emplace(row, cur_row);
   }
   mappings_.emplace(id, cur_row);
   return cur_row;
 }

 int64_t HeapProfileTracker::AddFrame(SourceFrameId id,
                                      const SourceFrame& frame,
                                      const InternLookup* intern_lookup) {
   auto opt_str_id = FindString(frame.name_id, intern_lookup);
   if (!opt_str_id) {
     context_->storage->IncrementStats(stats::heapprofd_invalid_string_id);
     PERFETTO_DFATAL("Invalid string.");
     return -1;
   }
   const StringId& str_id = opt_str_id.value();

   auto maybe_mapping = FindMapping(frame.mapping_id, intern_lookup);
   if (!maybe_mapping) {
     context_->storage->IncrementStats(stats::heapprofd_invalid_mapping_id);
     PERFETTO_DFATAL("Invalid mapping.");
     return -1;
   }
   int64_t mapping_row = *maybe_mapping;

   TraceStorage::HeapProfileFrames::Row row{str_id, mapping_row,
                                            static_cast<int64_t>(frame.rel_pc)};

   int64_t cur_row;
   auto it = frame_idx_.find(row);
   if (it != frame_idx_.end()) {
     cur_row = it->second;
   } else {
     cur_row = context_->storage->mutable_heap_profile_frames()->Insert(row);
     frame_idx_.emplace(row, cur_row);
   }
   frames_.emplace(id, cur_row);
   return cur_row;
 }

 int64_t HeapProfileTracker::AddCallstack(SourceCallstackId id,
                                          const SourceCallstack& frame_ids,
                                          const InternLookup* intern_lookup) {
   // TODO(fmayer): This should be NULL.
   int64_t parent_id = -1;
   for (size_t depth = 0; depth < frame_ids.size(); ++depth) {
     std::vector<SourceFrameId> frame_subset = frame_ids;
     frame_subset.resize(depth + 1);
     auto self_it = callstacks_from_frames_.find(frame_subset);
     if (self_it != callstacks_from_frames_.end()) {
       parent_id = self_it->second;
       continue;
     }

     SourceFrameId frame_id = frame_ids[depth];
     auto maybe_frame_row = FindFrame(frame_id, intern_lookup);
     if (!maybe_frame_row) {
       context_->storage->IncrementStats(stats::heapprofd_invalid_frame_id);
       PERFETTO_DFATAL("Unknown frames.");
       return -1;
     }
     int64_t frame_row = *maybe_frame_row;

     TraceStorage::HeapProfileCallsites::Row row{static_cast<int64_t>(depth),
                                                 parent_id, frame_row};

     int64_t self_id;
     auto callsite_it = callsite_idx_.find(row);
     if (callsite_it != callsite_idx_.end()) {
       self_id = callsite_it->second;
     } else {
       self_id =
           context_->storage->mutable_heap_profile_callsites()->Insert(row);
       callsite_idx_.emplace(row, self_id);
     }
     parent_id = self_id;
   }
   callstacks_.emplace(id, parent_id);
   return parent_id;
 }

 void HeapProfileTracker::AddAllocation(const SourceAllocation& alloc,
                                        const InternLookup* intern_lookup) {
   auto maybe_callstack_id = FindCallstack(alloc.callstack_id, intern_lookup);
   if (!maybe_callstack_id) {
     context_->storage->IncrementStats(stats::heapprofd_invalid_callstack_id);
     PERFETTO_DFATAL("Unknown callstack %" PRIu64 " : %zu", alloc.callstack_id,
                     callstacks_.size());
     return;
   }

   int64_t callstack_id = *maybe_callstack_id;

   UniquePid upid = context_->process_tracker->GetOrCreateProcess(
       static_cast<uint32_t>(alloc.pid));

   TraceStorage::HeapProfileAllocations::Row alloc_row{
       alloc.timestamp, upid, callstack_id,
       static_cast<int64_t>(alloc.alloc_count),
       static_cast<int64_t>(alloc.self_allocated)};

   TraceStorage::HeapProfileAllocations::Row free_row{
       alloc.timestamp, upid, callstack_id,
       -static_cast<int64_t>(alloc.free_count),
       -static_cast<int64_t>(alloc.self_freed)};

   TraceStorage::HeapProfileAllocations::Row alloc_delta = alloc_row;
   TraceStorage::HeapProfileAllocations::Row free_delta = free_row;

   auto prev_alloc_it = prev_alloc_.find({upid, callstack_id});
   if (prev_alloc_it == prev_alloc_.end()) {
     std::tie(prev_alloc_it, std::ignore) =
         prev_alloc_.emplace(std::make_pair(upid, callstack_id),
                             TraceStorage::HeapProfileAllocations::Row{});
   }

   TraceStorage::HeapProfileAllocations::Row& prev_alloc = prev_alloc_it->second;
   alloc_delta.count -= prev_alloc.count;
   alloc_delta.size -= prev_alloc.size;

   auto prev_free_it = prev_free_.find({upid, callstack_id});
   if (prev_free_it == prev_free_.end()) {
     std::tie(prev_free_it, std::ignore) =
         prev_free_.emplace(std::make_pair(upid, callstack_id),
                            TraceStorage::HeapProfileAllocations::Row{});
   }

   TraceStorage::HeapProfileAllocations::Row& prev_free = prev_free_it->second;
   free_delta.count -= prev_free.count;
   free_delta.size -= prev_free.size;

   if (alloc_delta.count)
     context_->storage->mutable_heap_profile_allocations()->Insert(alloc_delta);
   if (free_delta.count)
     context_->storage->mutable_heap_profile_allocations()->Insert(free_delta);

   prev_alloc = alloc_row;
   prev_free = free_row;
 }

 void HeapProfileTracker::StoreAllocation(SourceAllocation alloc) {
   pending_allocs_.emplace_back(std::move(alloc));
 }

 void HeapProfileTracker::CommitAllocations(const InternLookup* intern_lookup) {
   for (const auto& p : pending_allocs_)
     AddAllocation(p, intern_lookup);
   pending_allocs_.clear();
 }

 void HeapProfileTracker::FinalizeProfile(const InternLookup* intern_lookup) {
   CommitAllocations(intern_lookup);

   string_map_.clear();
   mappings_.clear();
   frames_.clear();
   callstacks_from_frames_.clear();
   callstacks_.clear();
 }

 int64_t HeapProfileTracker::GetDatabaseFrameIdForTesting(
     SourceFrameId frame_id) {
   auto it = frames_.find(frame_id);
   if (it == frames_.end()) {
     PERFETTO_DFATAL("Invalid frame.");
     return -1;
   }
   return it->second;
 }

 base::Optional<StringId> HeapProfileTracker::FindString(
     SourceStringId id,
     const InternLookup* intern_lookup) {
   base::Optional<StringId> res;
   if (id == 0) {
     res = empty_;
     return res;
   }

   auto it = string_map_.find(id);
   if (it == string_map_.end()) {
     if (intern_lookup) {
       auto interned_str = intern_lookup->GetString(id);
       if (interned_str)
         return interned_str;
     }
     context_->storage->IncrementStats(stats::heapprofd_invalid_string_id);
     PERFETTO_DFATAL("Invalid string.");
     return res;
   }
   res = it->second;
   return res;
 }

 base::Optional<int64_t> HeapProfileTracker::FindMapping(
     SourceMappingId mapping_id,
     const InternLookup* intern_lookup) {
   base::Optional<int64_t> res;
   auto it = mappings_.find(mapping_id);
   if (it == mappings_.end()) {
     if (intern_lookup) {
       auto interned_mapping = intern_lookup->GetMapping(mapping_id);
       if (interned_mapping) {
         res = AddMapping(mapping_id, *interned_mapping, intern_lookup);
         return res;
       }
     }
     context_->storage->IncrementStats(stats::heapprofd_invalid_mapping_id);
     PERFETTO_DFATAL("Unknown mapping %" PRIu64 " : %zu", mapping_id,
                     mappings_.size());
     return res;
   }
   res = it->second;
   return res;
 }

 base::Optional<int64_t> HeapProfileTracker::FindFrame(
     SourceFrameId frame_id,
     const InternLookup* intern_lookup) {
   base::Optional<int64_t> res;
   auto it = frames_.find(frame_id);
   if (it == frames_.end()) {
     if (intern_lookup) {
       auto interned_frame = intern_lookup->GetFrame(frame_id);
       if (interned_frame) {
         res = AddFrame(frame_id, *interned_frame, intern_lookup);
         return res;
       }
     }
     context_->storage->IncrementStats(stats::heapprofd_invalid_frame_id);
     PERFETTO_DFATAL("Unknown frame %" PRIu64 " : %zu", frame_id,
                     frames_.size());
     return res;
   }
   res = it->second;
   return res;
 }

 base::Optional<int64_t> HeapProfileTracker::FindCallstack(
     SourceCallstackId callstack_id,
     const InternLookup* intern_lookup) {
   base::Optional<int64_t> res;
   auto it = callstacks_.find(callstack_id);
   if (it == callstacks_.end()) {
     auto interned_callstack = intern_lookup->GetCallstack(callstack_id);
     if (interned_callstack) {
       res = AddCallstack(callstack_id, *interned_callstack, intern_lookup);
       return res;
     }
     context_->storage->IncrementStats(stats::heapprofd_invalid_callstack_id);
     PERFETTO_DFATAL("Unknown callstack %" PRIu64 " : %zu", callstack_id,
                     callstacks_.size());
     return res;
   }
   res = it->second;
   return res;
 }

 }  // namespace trace_processor
 }  // namespace perfetto
	/*
	* Copyright (C) 2019 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 "src/trace_processor/heap_profile_tracker.h"

	#include "src/trace_processor/process_tracker.h"
	#include "src/trace_processor/trace_processor_context.h"

	#include "perfetto/base/logging.h"

	namespace perfetto {
	namespace trace_processor {
	namespace {

	std::string ToHex(const char* build_id, size_t size) {
	std::string hex_build_id(2 * size + 1, 'x');
	for (size_t i = 0; i < size; ++i) {
	// snprintf prints 3 characters, the two hex digits and a null byte. As we
	// write left to write, we keep overwriting the nullbytes, except for the
	// last call to snprintf.
	snprintf(&(hex_build_id[2 * i]), 3, "%02hhx", build_id[i]);
	}
	// Remove the trailing nullbyte produced by the last snprintf.
	hex_build_id.resize(2 * size);
	return hex_build_id;
	}

	} // namespace

	HeapProfileTracker::InternLookup::~InternLookup() = default;

	HeapProfileTracker::HeapProfileTracker(TraceProcessorContext* context)
	: context_(context), empty_(context_->storage->InternString({"", 0})) {}

	HeapProfileTracker::~HeapProfileTracker() = default;

	void HeapProfileTracker::AddString(SourceStringId id, StringId str) {
	string_map_.emplace(id, str);
	}

	int64_t HeapProfileTracker::AddMapping(SourceMappingId id,
	const SourceMapping& mapping,
	const InternLookup* intern_lookup) {
	auto opt_name_id = FindString(mapping.name_id, intern_lookup);
	if (!opt_name_id) {
	context_->storage->IncrementStats(stats::heapprofd_invalid_string_id);
	PERFETTO_DFATAL("Invalid string.");
	return -1;
	}
	const StringId name_id = opt_name_id.value();

	auto opt_build_id = FindString(mapping.build_id, intern_lookup);
	if (!opt_build_id) {
	context_->storage->IncrementStats(stats::heapprofd_invalid_string_id);
	PERFETTO_DFATAL("Invalid string.");
	return -1;
	}
	const StringId raw_build_id = opt_build_id.value();
	NullTermStringView raw_build_id_str =
	context_->storage->GetString(raw_build_id);
	StringId build_id = empty_;
	if (raw_build_id_str.size() > 0) {
	std::string hex_build_id =
	ToHex(raw_build_id_str.c_str(), raw_build_id_str.size());
	build_id = context_->storage->InternString(base::StringView(hex_build_id));
	}

	TraceStorage::HeapProfileMappings::Row row{
	build_id,
	static_cast<int64_t>(mapping.exact_offset),
	static_cast<int64_t>(mapping.start_offset),
	static_cast<int64_t>(mapping.start),
	static_cast<int64_t>(mapping.end),
	static_cast<int64_t>(mapping.load_bias),
	name_id};

	int64_t cur_row;
	auto it = mapping_idx_.find(row);
	if (it != mapping_idx_.end()) {
	cur_row = it->second;
	} else {
	cur_row = context_->storage->mutable_heap_profile_mappings()->Insert(row);
	mapping_idx_.emplace(row, cur_row);
	}
	mappings_.emplace(id, cur_row);
	return cur_row;
	}

	int64_t HeapProfileTracker::AddFrame(SourceFrameId id,
	const SourceFrame& frame,
	const InternLookup* intern_lookup) {
	auto opt_str_id = FindString(frame.name_id, intern_lookup);
	if (!opt_str_id) {
	context_->storage->IncrementStats(stats::heapprofd_invalid_string_id);
	PERFETTO_DFATAL("Invalid string.");
	return -1;
	}
	const StringId& str_id = opt_str_id.value();

	auto maybe_mapping = FindMapping(frame.mapping_id, intern_lookup);
	if (!maybe_mapping) {
	context_->storage->IncrementStats(stats::heapprofd_invalid_mapping_id);
	PERFETTO_DFATAL("Invalid mapping.");
	return -1;
	}
	int64_t mapping_row = *maybe_mapping;

	TraceStorage::HeapProfileFrames::Row row{str_id, mapping_row,
	static_cast<int64_t>(frame.rel_pc)};

	int64_t cur_row;
	auto it = frame_idx_.find(row);
	if (it != frame_idx_.end()) {
	cur_row = it->second;
	} else {
	cur_row = context_->storage->mutable_heap_profile_frames()->Insert(row);
	frame_idx_.emplace(row, cur_row);
	}
	frames_.emplace(id, cur_row);
	return cur_row;
	}

	int64_t HeapProfileTracker::AddCallstack(SourceCallstackId id,
	const SourceCallstack& frame_ids,
	const InternLookup* intern_lookup) {
	// TODO(fmayer): This should be NULL.
	int64_t parent_id = -1;
	for (size_t depth = 0; depth < frame_ids.size(); ++depth) {
	std::vector<SourceFrameId> frame_subset = frame_ids;
	frame_subset.resize(depth + 1);
	auto self_it = callstacks_from_frames_.find(frame_subset);
	if (self_it != callstacks_from_frames_.end()) {
	parent_id = self_it->second;
	continue;
	}

	SourceFrameId frame_id = frame_ids[depth];
	auto maybe_frame_row = FindFrame(frame_id, intern_lookup);
	if (!maybe_frame_row) {
	context_->storage->IncrementStats(stats::heapprofd_invalid_frame_id);
	PERFETTO_DFATAL("Unknown frames.");
	return -1;
	}
	int64_t frame_row = *maybe_frame_row;

	TraceStorage::HeapProfileCallsites::Row row{static_cast<int64_t>(depth),
	parent_id, frame_row};

	int64_t self_id;
	auto callsite_it = callsite_idx_.find(row);
	if (callsite_it != callsite_idx_.end()) {
	self_id = callsite_it->second;
	} else {
	self_id =
	context_->storage->mutable_heap_profile_callsites()->Insert(row);
	callsite_idx_.emplace(row, self_id);
	}
	parent_id = self_id;
	}
	callstacks_.emplace(id, parent_id);
	return parent_id;
	}

	void HeapProfileTracker::AddAllocation(const SourceAllocation& alloc,
	const InternLookup* intern_lookup) {
	auto maybe_callstack_id = FindCallstack(alloc.callstack_id, intern_lookup);
	if (!maybe_callstack_id) {
	context_->storage->IncrementStats(stats::heapprofd_invalid_callstack_id);
	PERFETTO_DFATAL("Unknown callstack %" PRIu64 " : %zu", alloc.callstack_id,
	callstacks_.size());
	return;
	}

	int64_t callstack_id = *maybe_callstack_id;

	UniquePid upid = context_->process_tracker->GetOrCreateProcess(
	static_cast<uint32_t>(alloc.pid));

	TraceStorage::HeapProfileAllocations::Row alloc_row{
	alloc.timestamp, upid, callstack_id,
	static_cast<int64_t>(alloc.alloc_count),
	static_cast<int64_t>(alloc.self_allocated)};

	TraceStorage::HeapProfileAllocations::Row free_row{
	alloc.timestamp, upid, callstack_id,
	-static_cast<int64_t>(alloc.free_count),
	-static_cast<int64_t>(alloc.self_freed)};

	TraceStorage::HeapProfileAllocations::Row alloc_delta = alloc_row;
	TraceStorage::HeapProfileAllocations::Row free_delta = free_row;

	auto prev_alloc_it = prev_alloc_.find({upid, callstack_id});
	if (prev_alloc_it == prev_alloc_.end()) {
	std::tie(prev_alloc_it, std::ignore) =
	prev_alloc_.emplace(std::make_pair(upid, callstack_id),
	TraceStorage::HeapProfileAllocations::Row{});
	}

	TraceStorage::HeapProfileAllocations::Row& prev_alloc = prev_alloc_it->second;
	alloc_delta.count -= prev_alloc.count;
	alloc_delta.size -= prev_alloc.size;

	auto prev_free_it = prev_free_.find({upid, callstack_id});
	if (prev_free_it == prev_free_.end()) {
	std::tie(prev_free_it, std::ignore) =
	prev_free_.emplace(std::make_pair(upid, callstack_id),
	TraceStorage::HeapProfileAllocations::Row{});
	}

	TraceStorage::HeapProfileAllocations::Row& prev_free = prev_free_it->second;
	free_delta.count -= prev_free.count;
	free_delta.size -= prev_free.size;

	if (alloc_delta.count)
	context_->storage->mutable_heap_profile_allocations()->Insert(alloc_delta);
	if (free_delta.count)
	context_->storage->mutable_heap_profile_allocations()->Insert(free_delta);

	prev_alloc = alloc_row;
	prev_free = free_row;
	}

	void HeapProfileTracker::StoreAllocation(SourceAllocation alloc) {
	pending_allocs_.emplace_back(std::move(alloc));
	}

	void HeapProfileTracker::CommitAllocations(const InternLookup* intern_lookup) {
	for (const auto& p : pending_allocs_)
	AddAllocation(p, intern_lookup);
	pending_allocs_.clear();
	}

	void HeapProfileTracker::FinalizeProfile(const InternLookup* intern_lookup) {
	CommitAllocations(intern_lookup);

	string_map_.clear();
	mappings_.clear();
	frames_.clear();
	callstacks_from_frames_.clear();
	callstacks_.clear();
	}

	int64_t HeapProfileTracker::GetDatabaseFrameIdForTesting(
	SourceFrameId frame_id) {
	auto it = frames_.find(frame_id);
	if (it == frames_.end()) {
	PERFETTO_DFATAL("Invalid frame.");
	return -1;
	}
	return it->second;
	}

	base::Optional<StringId> HeapProfileTracker::FindString(
	SourceStringId id,
	const InternLookup* intern_lookup) {
	base::Optional<StringId> res;
	if (id == 0) {
	res = empty_;
	return res;
	}

	auto it = string_map_.find(id);
	if (it == string_map_.end()) {
	if (intern_lookup) {
	auto interned_str = intern_lookup->GetString(id);
	if (interned_str)
	return interned_str;
	}
	context_->storage->IncrementStats(stats::heapprofd_invalid_string_id);
	PERFETTO_DFATAL("Invalid string.");
	return res;
	}
	res = it->second;
	return res;
	}

	base::Optional<int64_t> HeapProfileTracker::FindMapping(
	SourceMappingId mapping_id,
	const InternLookup* intern_lookup) {
	base::Optional<int64_t> res;
	auto it = mappings_.find(mapping_id);
	if (it == mappings_.end()) {
	if (intern_lookup) {
	auto interned_mapping = intern_lookup->GetMapping(mapping_id);
	if (interned_mapping) {
	res = AddMapping(mapping_id, *interned_mapping, intern_lookup);
	return res;
	}
	}
	context_->storage->IncrementStats(stats::heapprofd_invalid_mapping_id);
	PERFETTO_DFATAL("Unknown mapping %" PRIu64 " : %zu", mapping_id,
	mappings_.size());
	return res;
	}
	res = it->second;
	return res;
	}

	base::Optional<int64_t> HeapProfileTracker::FindFrame(
	SourceFrameId frame_id,
	const InternLookup* intern_lookup) {
	base::Optional<int64_t> res;
	auto it = frames_.find(frame_id);
	if (it == frames_.end()) {
	if (intern_lookup) {
	auto interned_frame = intern_lookup->GetFrame(frame_id);
	if (interned_frame) {
	res = AddFrame(frame_id, *interned_frame, intern_lookup);
	return res;
	}
	}
	context_->storage->IncrementStats(stats::heapprofd_invalid_frame_id);
	PERFETTO_DFATAL("Unknown frame %" PRIu64 " : %zu", frame_id,
	frames_.size());
	return res;
	}
	res = it->second;
	return res;
	}

	base::Optional<int64_t> HeapProfileTracker::FindCallstack(
	SourceCallstackId callstack_id,
	const InternLookup* intern_lookup) {
	base::Optional<int64_t> res;
	auto it = callstacks_.find(callstack_id);
	if (it == callstacks_.end()) {
	auto interned_callstack = intern_lookup->GetCallstack(callstack_id);
	if (interned_callstack) {
	res = AddCallstack(callstack_id, *interned_callstack, intern_lookup);
	return res;
	}
	context_->storage->IncrementStats(stats::heapprofd_invalid_callstack_id);
	PERFETTO_DFATAL("Unknown callstack %" PRIu64 " : %zu", callstack_id,
	callstacks_.size());
	return res;
	}
	res = it->second;
	return res;
	}

	} // namespace trace_processor
	} // namespace perfetto