commit 5788fecdd344daf2a510bffad95ce844ca047a7f
author Avichal Rakesh <arakesh@google.com> Fri Mar 15 14:39:20 2024 -0700
committer Avichal Rakesh <arakesh@google.com> Mon Mar 18 13:21:59 2024 -0700
tree 3fae65c27ea361ca36c6d1bfb7f95f2034d0ec19
parent e52f5c58a66496f4f02d8f7bb29cea9300d3e399

cameraservice: cache IPermissionChecker and IPermissionController

CameraService makes frequent calls to PermissionChecker and
PermissionController services while handler application requests.
However it requests a new instance of both from the service manager
for each call. Retrieving an instance from service manager results
in a binder call, which can quickly add up if the application is
making frequent calls to CameraService.

To reduce the latency of fetching the services, this CL caches the
PermissionChecker and IPermissionController objects for the lifetime
of CameraService.

Bug: 326139956
Test: atest CtsCameraTestCases:PerformanceTest#testCameraLaunch
      passes.
Test: Verified by vendors that getCameraCharacteristics calls are
      faster.
Change-Id: I9d7471c00d43bb89135d4026dcb8016be234938b

services/camera/libcameraservice/utils/AttributionAndPermissionUtils.cpp

diff --git a/services/camera/libcameraservice/utils/AttributionAndPermissionUtils.cpp b/services/camera/libcameraservice/utils/AttributionAndPermissionUtils.cpp
index e63b30b..e8301c1 100644
--- a/services/camera/libcameraservice/utils/AttributionAndPermissionUtils.cpp
+++ b/services/camera/libcameraservice/utils/AttributionAndPermissionUtils.cpp
@@ -18,6 +18,7 @@
 
 #include <binder/AppOpsManager.h>
 #include <binder/PermissionController.h>
+#include <com_android_internal_camera_flags.h>
 #include <cutils/properties.h>
 #include <private/android_filesystem_config.h>
 
@@ -26,6 +27,8 @@
 
 namespace android {
 
+namespace flags = com::android::internal::camera::flags;
+
 const std::string AttributionAndPermissionUtils::sDumpPermission("android.permission.DUMP");
 const std::string AttributionAndPermissionUtils::sManageCameraPermission(
         "android.permission.MANAGE_CAMERA");
@@ -75,9 +78,16 @@
         return true;
     }
 
-    PermissionChecker permissionChecker;
-    return permissionChecker.checkPermissionForPreflight(toString16(permission), attributionSource,
-            toString16(message), attributedOpCode) != PermissionChecker::PERMISSION_HARD_DENIED;
+    if (!flags::cache_permission_services()) {
+        PermissionChecker permissionChecker;
+        return permissionChecker.checkPermissionForPreflight(
+                       toString16(permission), attributionSource, toString16(message),
+                       attributedOpCode) != PermissionChecker::PERMISSION_HARD_DENIED;
+    } else {
+        return mPermissionChecker->checkPermissionForPreflight(
+                       toString16(permission), attributionSource, toString16(message),
+                       attributedOpCode) != PermissionChecker::PERMISSION_HARD_DENIED;
+    }
 }
 
 // Can camera service trust the caller based on the calling UID?

services/camera/libcameraservice/utils/AttributionAndPermissionUtils.h

diff --git a/services/camera/libcameraservice/utils/AttributionAndPermissionUtils.h b/services/camera/libcameraservice/utils/AttributionAndPermissionUtils.h
index 7f4a1bd..830a8e8 100644
--- a/services/camera/libcameraservice/utils/AttributionAndPermissionUtils.h
+++ b/services/camera/libcameraservice/utils/AttributionAndPermissionUtils.h
@@ -32,7 +32,7 @@
  * caller.
  */
 class AttributionAndPermissionUtils {
-public:
+  public:
     AttributionAndPermissionUtils() { }
     virtual ~AttributionAndPermissionUtils() {}
 
@@ -90,11 +90,15 @@
     static const std::string sCameraOpenCloseListenerPermission;
     static const std::string sCameraInjectExternalCameraPermission;
 
-protected:
+  protected:
     wp<CameraService> mCameraService;
 
     bool checkAutomotivePrivilegedClient(const std::string &cameraId,
             const AttributionSourceState &attributionSource);
+
+  private:
+    std::unique_ptr<permission::PermissionChecker> mPermissionChecker =
+            std::make_unique<permission::PermissionChecker>();
 };
 
 /**