During lookup of critical JNI functions (CriticalJNINatives) we execute OS functions to deal with dlls (e.g. dlopen, dlsym). These functions need to perform I/O which may be slow.
The current implementation executes these functions while the thread is in state "_thread_in_vm". This means that the thread blocks safepoints while performing I/O.
In order to reduce safepoint delays, I/O should be executed while the thread is in state "_thread_in_native" which avoids blocking safepoints.