From 01e65629ff66663106cb1f24471a1cf5ab9d6e6e Mon Sep 17 00:00:00 2001
From: Kajari Ghosh <ghoshkaj@gmail.com>
Date: Mon, 2 Apr 2018 15:28:29 -0400
Subject: [PATCH] put a lock infront of the clear function to make it
 threadsafe

---
 include/engine/search_engine_data.hpp | 5 ++++-
 src/engine/search_engine_data.cpp     | 1 +
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/include/engine/search_engine_data.hpp b/include/engine/search_engine_data.hpp
index b1aaec07329..a193254470b 100644
--- a/include/engine/search_engine_data.hpp
+++ b/include/engine/search_engine_data.hpp
@@ -6,7 +6,8 @@
 #include "util/query_heap.hpp"
 #include "util/typedefs.hpp"
 
-#include <boost/thread/tss.hpp>
+// #include <boost/thread/tss.hpp>
+#include <boost/thread.hpp>
 
 namespace osrm
 {
@@ -57,6 +58,8 @@ template <> struct SearchEngineData<routing_algorithms::ch::Algorithm>
     static ManyToManyHeapPtr many_to_many_heap;
     static UnpackingCache unpacking_cache;
 
+    boost::shared_mutex _shared_access_across_threads;
+
     void InitializeOrClearFirstThreadLocalStorage(unsigned number_of_nodes);
 
     void InitializeOrClearSecondThreadLocalStorage(unsigned number_of_nodes);
diff --git a/src/engine/search_engine_data.cpp b/src/engine/search_engine_data.cpp
index 88897a38462..bc7ad766b58 100644
--- a/src/engine/search_engine_data.cpp
+++ b/src/engine/search_engine_data.cpp
@@ -93,6 +93,7 @@ void SearchEngineData<CH>::InitializeOrClearManyToManyThreadLocalStorage(unsigne
 
 void SearchEngineData<CH>::InitializeOrClearUnpackingCacheGlobalStorage(unsigned timestamp)
 {
+    boost::unique_lock<boost::shared_mutex> lock(_shared_access_across_threads);
     unpacking_cache.Clear(timestamp);
 }