[SYCL][Graph] Fix race in node queries (#17012)

reble · web-flow · commit b79738b9391d · 2025-02-14T07:16:43.000-08:00
Found by coverity scan.
diff --git a/sycl/source/detail/graph_impl.cpp b/sycl/source/detail/graph_impl.cpp
@@ -1811,9 +1811,11 @@ void modifiable_command_graph::print_graph(sycl::detail::string_view pathstr,
 }
 
 std::vector<node> modifiable_command_graph::get_nodes() const {
+  graph_impl::ReadLock Lock(impl->MMutex);
   return createNodesFromImpls(impl->MNodeStorage);
 }
 std::vector<node> modifiable_command_graph::get_root_nodes() const {
+  graph_impl::ReadLock Lock(impl->MMutex);
   auto &Roots = impl->MRoots;
   std::vector<std::weak_ptr<node_impl>> Impls{};
 

Original file line number	Diff line number	Diff line change
`@@ -1811,9 +1811,11 @@ void modifiable_command_graph::print_graph(sycl::detail::string_view pathstr,`
`1811`	`1811`	`}`
`1812`	`1812`
`1813`	`1813`	`std::vector<node> modifiable_command_graph::get_nodes() const {`
	`1814`	`+ graph_impl::ReadLock Lock(impl->MMutex);`
`1814`	`1815`	`return createNodesFromImpls(impl->MNodeStorage);`
`1815`	`1816`	`}`
`1816`	`1817`	`std::vector<node> modifiable_command_graph::get_root_nodes() const {`
	`1818`	`+ graph_impl::ReadLock Lock(impl->MMutex);`
`1817`	`1819`	`auto &Roots = impl->MRoots;`
`1818`	`1820`	`std::vector<std::weak_ptr<node_impl>> Impls{};`
`1819`	`1821`