diff --git a/tools/profiler/core/Sampler.cpp b/tools/profiler/core/Sampler.cpp
index afe15da6f5d6..adb35661c9d6 100644
--- a/tools/profiler/core/Sampler.cpp
+++ b/tools/profiler/core/Sampler.cpp
@@ -170,7 +170,7 @@ Sampler::Sampler()
     for (uint32_t i = 0; i < sRegisteredThreads->size(); i++) {
       ThreadInfo* info = sRegisteredThreads->at(i);
 
-      RegisterThread(info);
+      MaybeSetProfile(info);
     }
   }
 
@@ -530,42 +530,3 @@ void PseudoStack::flushSamplerOnJSShutdown()
 // END SaveProfileTask et al
 ////////////////////////////////////////////////////////////////////////
 
-static bool
-ThreadSelected(const char* aThreadName)
-{
-  StaticMutexAutoLock lock(gThreadNameFiltersMutex);
-
-  if (gThreadNameFilters.empty()) {
-    return true;
-  }
-
-  std::string name = aThreadName;
-  std::transform(name.begin(), name.end(), name.begin(), ::tolower);
-
-  for (uint32_t i = 0; i < gThreadNameFilters.length(); ++i) {
-    std::string filter = gThreadNameFilters[i];
-    std::transform(filter.begin(), filter.end(), filter.begin(), ::tolower);
-
-    // Crude, non UTF-8 compatible, case insensitive substring search
-    if (name.find(filter) != std::string::npos) {
-      return true;
-    }
-  }
-
-  return false;
-}
-
-void
-Sampler::RegisterThread(ThreadInfo* aInfo)
-{
-  if (!aInfo->IsMainThread() && !gProfileThreads) {
-    return;
-  }
-
-  if (!ThreadSelected(aInfo->Name())) {
-    return;
-  }
-
-  aInfo->SetProfile(gBuffer);
-}
-
diff --git a/tools/profiler/core/platform.cpp b/tools/profiler/core/platform.cpp
index 753c2e2f96ce..a255051bd35b 100644
--- a/tools/profiler/core/platform.cpp
+++ b/tools/profiler/core/platform.cpp
@@ -1167,6 +1167,40 @@ GeckoProfilerReporter::CollectReports(nsIHandleReportCallback* aHandleReport,
 
 NS_IMPL_ISUPPORTS(GeckoProfilerReporter, nsIMemoryReporter)
 
+static bool
+ThreadSelected(const char* aThreadName)
+{
+  StaticMutexAutoLock lock(gThreadNameFiltersMutex);
+
+  if (gThreadNameFilters.empty()) {
+    return true;
+  }
+
+  std::string name = aThreadName;
+  std::transform(name.begin(), name.end(), name.begin(), ::tolower);
+
+  for (uint32_t i = 0; i < gThreadNameFilters.length(); ++i) {
+    std::string filter = gThreadNameFilters[i];
+    std::transform(filter.begin(), filter.end(), filter.begin(), ::tolower);
+
+    // Crude, non UTF-8 compatible, case insensitive substring search
+    if (name.find(filter) != std::string::npos) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+static void
+MaybeSetProfile(ThreadInfo* aInfo)
+{
+  if ((aInfo->IsMainThread() || gProfileThreads) &&
+      ThreadSelected(aInfo->Name())) {
+    aInfo->SetProfile(gBuffer);
+  }
+}
+
 static void
 RegisterCurrentThread(const char* aName, PseudoStack* aPseudoStack,
                       bool aIsMainThread, void* stackTop)
@@ -1192,10 +1226,7 @@ RegisterCurrentThread(const char* aName, PseudoStack* aPseudoStack,
   ThreadInfo* info =
     new ThreadInfo(aName, id, aIsMainThread, aPseudoStack, stackTop);
 
-  // XXX: this is an off-main-thread use of gSampler
-  if (gSampler) {
-    gSampler->RegisterThread(info);
-  }
+  MaybeSetProfile(info);
 
   sRegisteredThreads->push_back(info);
 }
@@ -1586,7 +1617,7 @@ profiler_start(int aProfileEntries, double aInterval,
   profiler_stop();
 
   // Deep copy aThreadNameFilters. Must happen before Sampler's constructor
-  // calls RegisterThread().
+  // calls MaybeSetProfile().
   {
     StaticMutexAutoLock lock(gThreadNameFiltersMutex);
 
diff --git a/tools/profiler/core/platform.h b/tools/profiler/core/platform.h
index c4488b68b284..410e1c35b60b 100644
--- a/tools/profiler/core/platform.h
+++ b/tools/profiler/core/platform.h
@@ -221,8 +221,6 @@ public:
   Sampler();
   ~Sampler();
 
-  void RegisterThread(ThreadInfo* aInfo);
-
   void ToStreamAsJSON(std::ostream& stream, double aSinceTime = 0);
   JSObject *ToJSObject(JSContext *aCx, double aSinceTime = 0);
   mozilla::UniquePtr<char[]> ToJSON(double aSinceTime = 0);