From 260c6f5e5f796fbc9eb4b84b60632e48c53a61e5 Mon Sep 17 00:00:00 2001
From: Eugene Zhulenev <ezhulenev@google.com>
Date: Sat, 26 Jun 2021 07:34:43 -0700
Subject: [PATCH] [perf] Fix a data race in the PerfJITEventListener

Concurrent JIT compilation + PerfJITEventListener triggers tsan error

Reviewed By: cota

Differential Revision: https://reviews.llvm.org/D104977
---
 lib/ExecutionEngine/PerfJITEvents/PerfJITEventListener.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/ExecutionEngine/PerfJITEvents/PerfJITEventListener.cpp b/lib/ExecutionEngine/PerfJITEvents/PerfJITEventListener.cpp
index d4c715cc59f..4a236e183c8 100644
--- a/lib/ExecutionEngine/PerfJITEvents/PerfJITEventListener.cpp
+++ b/lib/ExecutionEngine/PerfJITEvents/PerfJITEventListener.cpp
@@ -284,6 +284,9 @@ void PerfJITEventListener::notifyObjectLoaded(
     NotifyCode(Name, *AddrOrErr, Size);
   }
 
+  // avoid races with writes
+  std::lock_guard<sys::Mutex> Guard(Mutex);
+
   Dumpstream->flush();
 }