Allow thread-safe access to add/remove code event observers.

BUG=406277

Review-Url: https://codereview.chromium.org/2321073004
Cr-Commit-Position: refs/heads/master@{#39853}

src/code-events.h

@@ -7,6 +7,7 @@
 
 #include <unordered_set>
 
+#include "src/base/platform/mutex.h"
 #include "src/globals.h"
 
 namespace v8 {
@@ -114,13 +115,16 @@ class CodeEventDispatcher {
   CodeEventDispatcher() {}
 
   bool AddListener(CodeEventListener* listener) {
+    base::LockGuard<base::Mutex> guard(&mutex_);
     return listeners_.insert(listener).second;
   }
   void RemoveListener(CodeEventListener* listener) {
+    base::LockGuard<base::Mutex> guard(&mutex_);
     listeners_.erase(listener);
   }
 
 #define CODE_EVENT_DISPATCH(code)              \
+  base::LockGuard<base::Mutex> guard(&mutex_); \
   for (auto it = listeners_.begin(); it != listeners_.end(); ++it) (*it)->code
 
   void CodeCreateEvent(LogEventsAndTags tag, AbstractCode* code,
@@ -173,6 +177,7 @@ class CodeEventDispatcher {
 
  private:
   std::unordered_set<CodeEventListener*> listeners_;
+  base::Mutex mutex_;
 
   DISALLOW_COPY_AND_ASSIGN(CodeEventDispatcher);
 };

src/profiler/profiler-listener.cc

@@ -319,6 +319,7 @@ CodeEntry* ProfilerListener::NewCodeEntry(
 }
 
 void ProfilerListener::AddObserver(CodeEventObserver* observer) {
+  base::LockGuard<base::Mutex> guard(&mutex_);
   if (std::find(observers_.begin(), observers_.end(), observer) !=
       observers_.end())
     return;
@@ -326,6 +327,7 @@ void ProfilerListener::AddObserver(CodeEventObserver* observer) {
 }
 
 void ProfilerListener::RemoveObserver(CodeEventObserver* observer) {
+  base::LockGuard<base::Mutex> guard(&mutex_);
   auto it = std::find(observers_.begin(), observers_.end(), observer);
   if (it == observers_.end()) return;
   observers_.erase(it);

src/profiler/profiler-listener.h

@@ -79,6 +79,7 @@ class ProfilerListener : public CodeEventListener {
   void RecordDeoptInlinedFrames(CodeEntry* entry, AbstractCode* abstract_code);
   Name* InferScriptName(Name* name, SharedFunctionInfo* info);
   V8_INLINE void DispatchCodeEvent(const CodeEventsContainer& evt_rec) {
+    base::LockGuard<base::Mutex> guard(&mutex_);
     for (auto observer : observers_) {
       observer->CodeEventHandler(evt_rec);
     }
@@ -87,6 +88,7 @@ class ProfilerListener : public CodeEventListener {
   StringsStorage function_and_resource_names_;
   std::vector<CodeEntry*> code_entries_;
   std::vector<CodeEventObserver*> observers_;
+  base::Mutex mutex_;
 
   DISALLOW_COPY_AND_ASSIGN(ProfilerListener);
 };