Replace CallStackProfileBuilder::Module with ModuleCache::Module

Bug: 851163, 804942
Change-Id: I4da05d9c4e3a4c12f8b3c851d074fa3cdf97679f
Reviewed-on: https://chromium-review.googlesource.com/1174953
Commit-Queue: Xi Cheng <chengx@chromium.org>
Reviewed-by: Mike Wittman <wittman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#583111}

components/metrics/call_stack_profile_builder.cc

@@ -4,10 +4,6 @@
 
 #include "components/metrics/call_stack_profile_builder.h"
 
-#include <stddef.h>
-
-#include <cstring>
-#include <map>
 #include <string>
 #include <utility>
 
@@ -17,8 +13,6 @@
 #include "base/metrics/metrics_hashes.h"
 #include "base/stl_util.h"
 
-using base::StackSamplingProfiler;
-
 namespace metrics {
 
 namespace {
@@ -80,10 +74,9 @@ uint64_t HashModuleFilename(const base::FilePath& filename) {
 
 // Transcode |sample| into |proto_sample|, using base addresses in |modules| to
 // compute module instruction pointer offsets.
-void CopySampleToProto(
-    const CallStackProfileBuilder::Sample& sample,
-    const std::vector<CallStackProfileBuilder::Module>& modules,
-    CallStackProfile::Sample* proto_sample) {
+void CopySampleToProto(const CallStackProfileBuilder::Sample& sample,
+                       const std::vector<base::ModuleCache::Module>& modules,
+                       CallStackProfile::Sample* proto_sample) {
   for (const auto& frame : sample.frames) {
     CallStackProfile::Entry* entry = proto_sample->add_entry();
     // A frame may not have a valid module. If so, we can't compute the
@@ -187,17 +180,6 @@ SampledProfile::TriggerEvent ToSampledProfileTriggerEvent(
 
 }  // namespace
 
-// CallStackProfileBuilder::Module --------------------------------------------
-
-CallStackProfileBuilder::Module::Module() : base_address(0u) {}
-
-CallStackProfileBuilder::Module::Module(uintptr_t base_address,
-                                        const std::string& id,
-                                        const base::FilePath& filename)
-    : base_address(base_address), id(id), filename(filename) {}
-
-CallStackProfileBuilder::Module::~Module() = default;
-
 // CallStackProfileBuilder::Frame ---------------------------------------------
 
 CallStackProfileBuilder::Frame::Frame(uintptr_t instruction_pointer,
@@ -240,8 +222,8 @@ void CallStackProfileBuilder::RecordAnnotations() {
 }
 
 void CallStackProfileBuilder::OnSampleCompleted(
-    std::vector<StackSamplingProfiler::Frame> frames) {
-  // Assemble sample_ first.
+    std::vector<base::StackSamplingProfiler::Frame> frames) {
+  // Assemble sample_ from |frames| first.
   for (const auto& frame : frames) {
     const base::ModuleCache::Module& module(frame.module);
     if (!module.is_valid) {
@@ -250,19 +232,18 @@ void CallStackProfileBuilder::OnSampleCompleted(
       continue;
     }
 
-    // Dedup modules.
+    // Dedup modules and cache them in modules_.
     auto loc = module_index_.find(module.base_address);
     if (loc == module_index_.end()) {
-      modules_.emplace_back(module.base_address, module.id, module.filename);
+      modules_.push_back(module);
       size_t index = modules_.size() - 1;
       loc = module_index_.insert(std::make_pair(module.base_address, index))
                 .first;
     }
-    // convert Frames to Frames.
     sample_.frames.emplace_back(frame.instruction_pointer, loc->second);
   }
 
-  // Write CallStackProfile::Sample protocol buffer message.
+  // Write CallStackProfile::Sample protocol buffer message based on sample_.
   int existing_sample_index = -1;
   auto location = sample_index_.find(sample_);
   if (location != sample_index_.end())
@@ -306,7 +287,7 @@ void CallStackProfileBuilder::OnProfileCompleted(
   module_index_.clear();
   sample_index_.clear();
 
-  // Assemble SampledProfile protocol buffer message and run the associated
+  // Assemble the SampledProfile protocol buffer message and run the associated
   // callback to pass it.
   SampledProfile sampled_profile;
   CallStackProfile* proto_profile =

components/metrics/call_stack_profile_builder.h

@@ -6,53 +6,31 @@
 #define COMPONENTS_METRICS_CALL_STACK_PROFILE_BUILDER_H_
 
 #include <map>
-#include <string>
 #include <vector>
 
 #include "base/callback.h"
-#include "base/files/file_path.h"
 #include "base/profiler/stack_sampling_profiler.h"
+#include "base/sampling_heap_profiler/module_cache.h"
 #include "components/metrics/call_stack_profile_params.h"
 #include "third_party/metrics_proto/sampled_profile.pb.h"
 
 namespace metrics {
 
-// CallStackProfileBuilder builds a CallStackProfile from the collected sampling
-// data.
-//
-// The results of the profile building -- a CallStackProfile, is encoded to
-// metrics.SampledProfile protocol message. The message is then passed to the
-// completed callback. A CallStackProfile contains a set of Samples and Modules,
-// and other sampling information. One Sample corresponds to a single recorded
-// stack, and the Modules record those modules associated with the recorded
-// stack frames.
+// CallStackProfileBuilder builds a SampledProfile in the protocol buffer
+// message format from the collected sampling data. The message is then passed
+// to the completed callback.
+
+// A SampledProfile message (third_party/metrics_proto/sampled_profile.proto)
+// contains a CallStackProfile message
+// (third_party/metrics_proto/call_stack_profile.proto) and associated profile
+// parameters (process/thread/trigger event). A CallStackProfile message
+// contains a set of Sample messages and ModuleIdentifier messages, and other
+// sampling information. One Sample corresponds to a single recorded stack, and
+// the ModuleIdentifiers record those modules associated with the recorded stack
+// frames.
 class CallStackProfileBuilder
     : public base::StackSamplingProfiler::ProfileBuilder {
  public:
-  // Module represents the module (DLL or exe) corresponding to a stack frame.
-  struct Module {
-    Module();
-    Module(uintptr_t base_address,
-           const std::string& id,
-           const base::FilePath& filename);
-    ~Module();
-
-    // Points to the base address of the module.
-    uintptr_t base_address;
-
-    // An opaque binary string that uniquely identifies a particular program
-    // version with high probability. This is parsed from headers of the loaded
-    // module.
-    // For binaries generated by GNU tools:
-    //   Contents of the .note.gnu.build-id field.
-    // On Windows:
-    //   GUID + AGE in the debug image headers of a module.
-    std::string id;
-
-    // The filename of the module.
-    base::FilePath filename;
-  };
-
   // Frame represents an individual sampled stack frame with module information.
   struct Frame {
     Frame(uintptr_t instruction_pointer, size_t module_index);
@@ -153,7 +131,7 @@ class CallStackProfileBuilder
   std::map<uintptr_t, size_t> module_index_;
 
   // The distinct modules in the current profile.
-  std::vector<Module> modules_;
+  std::vector<base::ModuleCache::Module> modules_;
 
   // The process milestones of a previous sample.
   uint32_t milestones_ = 0;