libbinder: more forcePersist docs
Documenting recommending use for now. Looked at adding a shared library
destructor, but this has limited use when people use _exit, when persist
HALs sometimes exit manually early, and since it only corresponds to
this one mechanism. Given perf team work targetting understanding memory
uses/process which are starting, we can focus/rely on more general
infrastructure.
Fixes: 187946888
Test: N/A
Change-Id: I67c2477bccd9ebc789e20527d5692ea3a107c675
diff --git a/libs/binder/include/binder/LazyServiceRegistrar.h b/libs/binder/include/binder/LazyServiceRegistrar.h
index 9659732..f3ba830 100644
--- a/libs/binder/include/binder/LazyServiceRegistrar.h
+++ b/libs/binder/include/binder/LazyServiceRegistrar.h
@@ -50,8 +50,12 @@
int dumpFlags = IServiceManager::DUMP_FLAG_PRIORITY_DEFAULT);
/**
* Force the service to persist, even when it has 0 clients.
- * If setting this flag from the server side, make sure to do so before calling registerService,
- * or there may be a race with the default dynamic shutdown.
+ * If setting this flag from the server side, make sure to do so before calling
+ * registerService, or there may be a race with the default dynamic shutdown.
+ *
+ * This should only be used if it is every eventually set to false. If a
+ * service needs to persist but doesn't need to dynamically shut down,
+ * prefer to control it with another mechanism such as ctl.start.
*/
void forcePersist(bool persist);
diff --git a/libs/binder/ndk/include_platform/android/binder_manager.h b/libs/binder/ndk/include_platform/android/binder_manager.h
index a90b4aa..db72067 100644
--- a/libs/binder/ndk/include_platform/android/binder_manager.h
+++ b/libs/binder/ndk/include_platform/android/binder_manager.h
@@ -135,6 +135,10 @@
/**
* Prevent lazy services without client from shutting down their process
*
+ * This should only be used if it is every eventually set to false. If a
+ * service needs to persist but doesn't need to dynamically shut down,
+ * prefer to control it with another mechanism.
+ *
* \param persist 'true' if the process should not exit.
*/
void AServiceManager_forceLazyServicesPersist(bool persist) __INTRODUCED_IN(31);