SL-18721 Viewer shutdown order changes

Same thing as commit cf692c40b0b9f8d0d04cd10a02a84e3f697a2e99
which was removed due to shutdown freezes.
Error thread is no longer there so doesn't cause any race sonditions,
was not able to repro any issues so will ask QA to test shutdown

2 files changed, 12 insertions, 3 deletions

diff --git a/indra/llcommon/threadpool.cpp b/indra/llcommon/threadpool.cpp
index d5adf11264..22bbff4478 100644
--- a/indra/llcommon/threadpool.cpp
+++ b/indra/llcommon/threadpool.cpp
@@ -21,11 +21,12 @@
 #include "llevents.h"
 #include "stringize.h"
 
-LL::ThreadPool::ThreadPool(const std::string& name, size_t threads, size_t capacity):
+LL::ThreadPool::ThreadPool(const std::string& name, size_t threads, size_t capacity, bool auto_shutdown):
     super(name),
     mQueue(name, capacity),
     mName("ThreadPool:" + name),
-    mThreadCount(threads)
+    mThreadCount(threads),
+    mAutomaticShutdown(auto_shutdown)
 {}
 
 void LL::ThreadPool::start()
@@ -39,6 +40,13 @@ void LL::ThreadPool::start()
                 run(tname);
             });
     }
+
+    // Some threads might need to run longer than LLEventPumps
+    if (!mAutomaticShutdown)
+    {
+        return;
+    }
+
     // Listen on "LLApp", and when the app is shutting down, close the queue
     // and join the workers.
     LLEventPumps::instance().obtain("LLApp").listen(
diff --git a/indra/llcommon/threadpool.h b/indra/llcommon/threadpool.h
index f8eec3b457..22c875edb9 100644
--- a/indra/llcommon/threadpool.h
+++ b/indra/llcommon/threadpool.h
@@ -31,7 +31,7 @@ namespace LL
          * Pass ThreadPool a string name. This can be used to look up the
          * relevant WorkQueue.
          */
-        ThreadPool(const std::string& name, size_t threads=1, size_t capacity=1024);
+        ThreadPool(const std::string& name, size_t threads=1, size_t capacity=1024, bool auto_shutdown = true);
         virtual ~ThreadPool();
 
         /**
@@ -66,6 +66,7 @@ namespace LL
         std::string mName;
         size_t mThreadCount;
         std::vector<std::pair<std::string, std::thread>> mThreads;
+        bool mAutomaticShutdown;
     };
 
 } // namespace LL