Read "gctype" flag from namespace "runtime_native_boot".

ART does not support changing the garbage collector type/configuration
dynamically at the moment, so we can only change it when the runtime
starts, i.e. at boot time.

Also materialize "gctype" and "runtime_native_boot" as named constants.

Bug: 120794191
Bug: 72446017
Test: adb shell device_config put runtime_native_boot gctype nogenerational_cc && adb reboot
Test: adb shell device_config put runtime_native_boot gctype generational_cc && adb reboot
Change-Id: Ibf765a5f442136d6327be99786ea9ae4b4537d59

1 files changed, 8 insertions, 1 deletions

diff --git a/core/jni/AndroidRuntime.cpp b/core/jni/AndroidRuntime.cpp
index 49598bbb5ada..d69d416e8401 100644
--- a/core/jni/AndroidRuntime.cpp
+++ b/core/jni/AndroidRuntime.cpp
@@ -230,6 +230,11 @@ extern int register_com_android_internal_os_Zygote(JNIEnv *env);
 extern int register_com_android_internal_os_ZygoteInit(JNIEnv *env);
 extern int register_com_android_internal_util_VirtualRefBasePtr(JNIEnv *env);
 
+// Namespace for Android Runtime flags applied during boot time.
+static const char* RUNTIME_NATIVE_BOOT_NAMESPACE = "runtime_native_boot";
+// Feature flag name for Garbage Collector type.
+static const char* GCTYPE = "gctype";
+
 static AndroidRuntime* gCurRuntime = NULL;
 
 /*
@@ -776,7 +781,9 @@ int AndroidRuntime::startVm(JavaVM** pJavaVM, JNIEnv** pEnv, bool zygote)
     }
 
     std::string gc_type_override =
-            server_configurable_flags::GetServerConfigurableFlag("runtime_native", "gctype", "");
+            server_configurable_flags::GetServerConfigurableFlag(RUNTIME_NATIVE_BOOT_NAMESPACE,
+                                                                 GCTYPE,
+                                                                 /*default_value=*/ "");
     std::string gc_type_override_temp;
     if (gc_type_override.empty()) {
         parseRuntimeOption("dalvik.vm.gctype", gctypeOptsBuf, "-Xgc:");