commit 9a61fa6bdc8724cc66eba532360e0e48b6b1a60e
author Matthew Bentham <Matthew.Bentham@arm.com> Tue Feb 04 10:03:55 2020 +0000
committer Derek Lamberti <derek.lamberti@arm.com> Tue Feb 04 13:13:46 2020 +0000
tree 547a2e5db5af7517171a84c9395ac9c42151e6db
parent 3d8bc97ff2250b230b105b3df34d1ef3efd82d2c

Github #273 Handle failure to initialise BackendContext in Runtime

Define CreateBackendContext to throw BackendUnavailableException
if necessary runtime components are missing.

Handle this in the constructor of Runtime by not adding those
backends to the internal DeviceSpec owned by the Runtime.

Signed-off-by: Matthew Bentham <Matthew.Bentham@arm.com>
Change-Id: Iadffb5240e32e1f105683c4d361276b92d1e720c

src/armnn/DeviceSpec.hpp

diff --git a/src/armnn/DeviceSpec.hpp b/src/armnn/DeviceSpec.hpp
index 703a4b1..a1457cf 100644
--- a/src/armnn/DeviceSpec.hpp
+++ b/src/armnn/DeviceSpec.hpp
@@ -14,6 +14,9 @@
 class DeviceSpec : public IDeviceSpec
 {
 public:
+    DeviceSpec()
+    {}
+
     DeviceSpec(const BackendIdSet& supportedBackends)
         : m_SupportedBackends{supportedBackends} {}
 
@@ -48,7 +51,6 @@
     }
 
 private:
-    DeviceSpec() = delete;
     BackendIdSet m_SupportedBackends;
     BackendIdSet m_DynamicBackends;
 };

src/armnn/Runtime.cpp

diff --git a/src/armnn/Runtime.cpp b/src/armnn/Runtime.cpp
index 2d7269a..47c998a 100644
--- a/src/armnn/Runtime.cpp
+++ b/src/armnn/Runtime.cpp
@@ -153,7 +153,6 @@
 
 Runtime::Runtime(const CreationOptions& options)
     : m_NetworkIdCounter(0)
-    , m_DeviceSpec{BackendRegistryInstance().GetBackendIds()}
 {
     ARMNN_LOG(info) << "ArmNN v" << ARMNN_VERSION << "\n";
 
@@ -164,12 +163,11 @@
     // goes through the backend registry
     LoadDynamicBackends(options.m_DynamicBackendsPath);
 
+    BackendIdSet supportedBackends;
     for (const auto& id : BackendRegistryInstance().GetBackendIds())
     {
         // Store backend contexts for the supported ones
-        const BackendIdSet& supportedBackends = m_DeviceSpec.GetSupportedBackends();
-        if (supportedBackends.find(id) != supportedBackends.end())
-        {
+        try {
             auto factoryFun = BackendRegistryInstance().GetFactory(id);
             auto backend = factoryFun();
             BOOST_ASSERT(backend.get() != nullptr);
@@ -182,8 +180,15 @@
             {
                 m_BackendContexts.emplace(std::make_pair(id, std::move(context)));
             }
+            supportedBackends.emplace(id);
         }
+        catch (const BackendUnavailableException&)
+        {
+            // Ignore backends which are unavailable
+        }
+
     }
+    m_DeviceSpec.AddSupportedBackends(supportedBackends);
 }
 
 Runtime::~Runtime()

src/armnn/Runtime.hpp

diff --git a/src/armnn/Runtime.hpp b/src/armnn/Runtime.hpp
index e5debbf..2ad3c96 100644
--- a/src/armnn/Runtime.hpp
+++ b/src/armnn/Runtime.hpp
@@ -73,8 +73,6 @@
     virtual void RegisterDebugCallback(NetworkId networkId, const DebugCallbackFunction& func) override;
 
     /// Creates a runtime for workload execution.
-    /// May throw a ClRuntimeUnavailableException if @a defaultComputeDevice requires a CL runtime but
-    /// it cannot be setup for some reason.
     Runtime(const CreationOptions& options);
 
     ~Runtime();