diff --git a/libs/hwui/ProfileDataContainer.cpp b/libs/hwui/ProfileDataContainer.cpp
index 38e0f0a..41afc0e 100644
--- a/libs/hwui/ProfileDataContainer.cpp
+++ b/libs/hwui/ProfileDataContainer.cpp
@@ -38,6 +38,8 @@
 }
 
 void ProfileDataContainer::rotateStorage() {
+    std::lock_guard lock(mJankDataMutex);
+
     // If we are mapped we want to stop using the ashmem backend and switch to malloc
     // We are expecting a switchStorageToAshmem call to follow this, but it's not guaranteed
     // If we aren't sitting on top of ashmem then just do a reset() as it's functionally
@@ -50,6 +52,7 @@
 }
 
 void ProfileDataContainer::switchStorageToAshmem(int ashmemfd) {
+    std::lock_guard lock(mJankDataMutex);
     int regionSize = ashmem_get_size_region(ashmemfd);
     if (regionSize < 0) {
         int err = errno;
@@ -70,7 +73,9 @@
         return;
     }
 
-    newData->mergeWith(*mData);
+    if (mData != nullptr) {
+        newData->mergeWith(*mData);
+    }
     freeData();
     mData = newData;
     mIsMapped = true;