Deregistering custom allocators in RuntimeImpl destructor.

Signed-off-by: Colm Donelan <colm.donelan@arm.com>
Change-Id: Ib148daf81700d9038d6e91a35c9c17e770c26e84

2 files changed, 14 insertions, 2 deletions

diff --git a/src/armnn/Runtime.cpp b/src/armnn/Runtime.cpp
index 75b1ee8179..cec54f4ec8 100644
--- a/src/armnn/Runtime.cpp
+++ b/src/armnn/Runtime.cpp
@@ -1,5 +1,5 @@
 //
-// Copyright © 2017 Arm Ltd and Contributors. All rights reserved.
+// Copyright © 2017, 2023 Arm Ltd and Contributors. All rights reserved.
 // SPDX-License-Identifier: MIT
 //
 
@@ -393,6 +393,7 @@ RuntimeImpl::RuntimeImpl(const IRuntime::CreationOptions& options)
                         }
                         // No errors so register the Custom Allocator with the BackendRegistry
                         BackendRegistryInstance().RegisterAllocator(id, customAllocatorMapIterator->second);
+                        m_AllocatorsAddedByThisRuntime.emplace(id);
                     }
                     else
                     {
@@ -428,6 +429,7 @@ RuntimeImpl::RuntimeImpl(const IRuntime::CreationOptions& options)
                     }
                     // No errors so register the Custom Allocator with the BackendRegistry
                     BackendRegistryInstance().RegisterAllocator(id, customAllocatorMapIterator->second);
+                    m_AllocatorsAddedByThisRuntime.emplace(id);
                 }
             }
 
@@ -584,6 +586,12 @@ RuntimeImpl::~RuntimeImpl()
     m_BackendContexts.clear();
 
     BackendRegistryInstance().SetProfilingService(armnn::EmptyOptional());
+    // Remove custom allocators that this runtime has added.
+    // Note: that as backends can be per process and there can be many instances of a runtime in a process an allocator
+    // may have been overwritten by another runtime.
+    for_each(m_AllocatorsAddedByThisRuntime.begin(), m_AllocatorsAddedByThisRuntime.end(),
+             [](BackendId id) {BackendRegistryInstance().DeregisterAllocator(id);});
+
     ARMNN_LOG(info) << "Shutdown time: " << std::setprecision(2)
                     << std::fixed << armnn::GetTimeDuration(startTime).count() << " ms.";
 }
diff --git a/src/armnn/Runtime.hpp b/src/armnn/Runtime.hpp
index f5dfadf948..9d47b7898d 100644
--- a/src/armnn/Runtime.hpp
+++ b/src/armnn/Runtime.hpp
@@ -1,5 +1,5 @@
 //
-// Copyright © 2017 Arm Ltd and Contributors. All rights reserved.
+// Copyright © 2017, 2023 Arm Ltd and Contributors. All rights reserved.
 // SPDX-License-Identifier: MIT
 //
 #pragma once
@@ -157,6 +157,10 @@ private:
 
     /// Profiling Service Instance
     std::unique_ptr<arm::pipe::IProfilingService> m_ProfilingService;
+
+    /// Keep track of backend ids of the custom allocators that this instance of the runtime added. The
+    /// destructor can then clean up for this runtime.
+    std::set<BackendId> m_AllocatorsAddedByThisRuntime;
 };
 
 } // namespace armnn