Merge "Disallow shrinking threadpool size once started." am: 70f592a6cf

Change-Id: I50c7b0aba4d22a08de0b78775c2c352e92bbbb95
diff --git a/libs/binder/ProcessState.cpp b/libs/binder/ProcessState.cpp
index 631e8c5..0f81e0b 100644
--- a/libs/binder/ProcessState.cpp
+++ b/libs/binder/ProcessState.cpp
@@ -328,6 +328,8 @@
 }
 
 status_t ProcessState::setThreadPoolMaxThreadCount(size_t maxThreads) {
+    LOG_ALWAYS_FATAL_IF(mThreadPoolStarted && maxThreads < mMaxThreads,
+           "Binder threadpool cannot be shrunk after starting");
     status_t result = NO_ERROR;
     if (ioctl(mDriverFD, BINDER_SET_MAX_THREADS, &maxThreads) != -1) {
         mMaxThreads = maxThreads;