Avoid race in single thread suspension.
Don't allow more than one concurrent single thread suspension to avoid
potential cycles and deadlocks where threads try to suspend each other.
Bug: 16364458, 16354227
Change-Id: I907f1d5591a6aa5c241d37d6b4a34f968f98df77
diff --git a/runtime/thread_list.h b/runtime/thread_list.h
index d46987a..1b67ac0 100644
--- a/runtime/thread_list.h
+++ b/runtime/thread_list.h
@@ -68,6 +68,7 @@
// is set to true.
static Thread* SuspendThreadByPeer(jobject peer, bool request_suspension, bool debug_suspension,
bool* timed_out)
+ EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_suspend_thread_lock_)
LOCKS_EXCLUDED(Locks::mutator_lock_,
Locks::thread_list_lock_,
Locks::thread_suspend_count_lock_);
@@ -77,6 +78,7 @@
// the thread terminating. Note that as thread ids are recycled this may not suspend the expected
// thread, that may be terminating. If the suspension times out then *timeout is set to true.
Thread* SuspendThreadByThreadId(uint32_t thread_id, bool debug_suspension, bool* timed_out)
+ EXCLUSIVE_LOCKS_REQUIRED(Locks::thread_list_suspend_thread_lock_)
LOCKS_EXCLUDED(Locks::mutator_lock_,
Locks::thread_list_lock_,
Locks::thread_suspend_count_lock_);