diff --git a/src/media_server_app.h b/src/media_server_app.h
deleted file mode 100644
index d94f9d5..0000000
--- a/src/media_server_app.h
+++ /dev/null
@@ -1,25 +0,0 @@
-#pragma once
-
-#include <atomic>
-#include <thread>
-#include <string>
-
-#include "graph_manager.h"
-
-namespace rk3588 {
-
-class MediaServerApp {
-public:
-    explicit MediaServerApp(std::string config_path);
-
-    int Start();
-
-private:
-    std::string config_path_;
-    GraphManager graph_manager_{};
-
-    std::atomic<bool> stop_signal_thread_{false};
-    std::thread signal_thread_;
-};
-
-}  // namespace rk3588
diff --git a/src/utils/dma_alloc.cpp b/src/utils/dma_alloc.cpp
index d2185b1..e16880c 100644
--- a/src/utils/dma_alloc.cpp
+++ b/src/utils/dma_alloc.cpp
@@ -1,5 +1,6 @@
 #include "utils/dma_alloc.h"
 
+#include <atomic>
 #include <cstdlib>
 #include <cerrno>
 #include <cstring>
@@ -189,7 +190,7 @@ DmaBufferPtr DmaAlloc(size_t alloc_size) {
         nullptr
     };
 
-    static bool first_success = true;
+    static std::atomic<bool> first_success{true};
 
     int dma_fd = -1;
     const char* used_heap = nullptr;
@@ -229,9 +230,8 @@ DmaBufferPtr DmaAlloc(size_t alloc_size) {
         return nullptr;
     }
 
-    if (first_success) {
+    if (first_success.exchange(false)) {
         LogInfo(std::string("[DmaAlloc] using heap: ") + (used_heap ? used_heap : "(unknown)"));
-        first_success = false;
     }
 
     void* ptr = mmap(nullptr, alloc_size, PROT_READ | PROT_WRITE, MAP_SHARED, dma_fd, 0);