Merge "libbinder*: Provide warning of library threadpool woes." am: 9c0835a838 am: 5eba053724 am: 96e7d2167a

Original change: https://android-review.googlesource.com/c/platform/frameworks/native/+/2329533

Change-Id: I5981cebaaa85378fe9117948457d27850afdb9b6
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

3 files changed, 14 insertions, 0 deletions

diff --git a/libs/binder/include/binder/IPCThreadState.h b/libs/binder/include/binder/IPCThreadState.h
index 65b77c6736..d261c2143c 100644
--- a/libs/binder/include/binder/IPCThreadState.h
+++ b/libs/binder/include/binder/IPCThreadState.h
@@ -141,11 +141,13 @@ public:
             void                restoreCallingIdentity(int64_t token);
             bool hasExplicitIdentity();
 
+            // For main functions - dangerous for libraries to use
             status_t            setupPolling(int* fd);
             status_t            handlePolledCommands();
             void                flushCommands();
             bool                flushIfNeeded();
 
+            // For main functions - dangerous for libraries to use
             void                joinThreadPool(bool isMain = true);
             
             // Stop the local process.
diff --git a/libs/binder/include/binder/ProcessState.h b/libs/binder/include/binder/ProcessState.h
index 9679a5f477..87eee3d0f2 100644
--- a/libs/binder/include/binder/ProcessState.h
+++ b/libs/binder/include/binder/ProcessState.h
@@ -50,6 +50,7 @@ public:
 
     sp<IBinder> getContextObject(const sp<IBinder>& caller);
 
+    // For main functions - dangerous for libraries to use
     void startThreadPool();
 
     bool becomeContextManager();
@@ -57,8 +58,10 @@ public:
     sp<IBinder> getStrongProxyForHandle(int32_t handle);
     void expungeHandle(int32_t handle, IBinder* binder);
 
+    // TODO: deprecate.
     void spawnPooledThread(bool isMain);
 
+    // For main functions - dangerous for libraries to use
     status_t setThreadPoolMaxThreadCount(size_t maxThreads);
     status_t enableOnewaySpamDetection(bool enable);
     void giveThreadPoolName();
diff --git a/libs/binder/ndk/include_platform/android/binder_process.h b/libs/binder/ndk/include_platform/android/binder_process.h
index f408fadee0..89231295dd 100644
--- a/libs/binder/ndk/include_platform/android/binder_process.h
+++ b/libs/binder/ndk/include_platform/android/binder_process.h
@@ -28,17 +28,26 @@ __BEGIN_DECLS
  *
  * When using this, it is expected that ABinderProcess_setupPolling and
  * ABinderProcess_handlePolledCommands are not used.
+ *
+ * Do not use this from a library. Apps setup their own threadpools, and otherwise, the main
+ * function should be responsible for configuring the threadpool for the entire application.
  */
 void ABinderProcess_startThreadPool();
 /**
  * This sets the maximum number of threads that can be started in the threadpool. By default, after
  * startThreadPool is called, this is 15. If it is called additional times, it will only prevent
  * the kernel from starting new threads and will not delete already existing threads.
+ *
+ * Do not use this from a library. Apps setup their own threadpools, and otherwise, the main
+ * function should be responsible for configuring the threadpool for the entire application.
  */
 bool ABinderProcess_setThreadPoolMaxThreadCount(uint32_t numThreads);
 /**
  * This adds the current thread to the threadpool. This may cause the threadpool to exceed the
  * maximum size.
+ *
+ * Do not use this from a library. Apps setup their own threadpools, and otherwise, the main
+ * function should be responsible for configuring the threadpool for the entire application.
  */
 void ABinderProcess_joinThreadPool();