Move thread state to art::Atomic.

Leaves the CAS operations as relaxed although art::Atomic treats relaxed CAS
as a strong CAS when not compiling with clang.

Change-Id: I6d37c22173540d166b624385e52e4ad05e592adc

1 files changed, 10 insertions, 8 deletions

diff --git a/runtime/thread-inl.h b/runtime/thread-inl.h
index b1180bd..38f1307 100644
--- a/runtime/thread-inl.h
+++ b/runtime/thread-inl.h
@@ -21,8 +21,6 @@
 
 #include <pthread.h>
 
-#include "cutils/atomic-inline.h"
-
 #include "base/casts.h"
 #include "base/mutex-inl.h"
 #include "gc/heap.h"
@@ -99,9 +97,12 @@ inline void Thread::TransitionFromRunnableToSuspended(ThreadState new_state) {
     DCHECK_EQ((old_state_and_flags.as_struct.flags & kCheckpointRequest), 0);
     new_state_and_flags.as_struct.flags = old_state_and_flags.as_struct.flags;
     new_state_and_flags.as_struct.state = new_state;
-    int status = android_atomic_cas(old_state_and_flags.as_int, new_state_and_flags.as_int,
-                                       &tls32_.state_and_flags.as_int);
-    if (LIKELY(status == 0)) {
+
+    // CAS the value without a memory ordering as that is given by the lock release below.
+    bool done =
+        tls32_.state_and_flags.as_atomic_int.CompareExchangeWeakRelaxed(old_state_and_flags.as_int,
+                                                                        new_state_and_flags.as_int);
+    if (LIKELY(done)) {
       break;
     }
   }
@@ -141,9 +142,10 @@ inline ThreadState Thread::TransitionFromSuspendedToRunnable() {
       union StateAndFlags new_state_and_flags;
       new_state_and_flags.as_int = old_state_and_flags.as_int;
       new_state_and_flags.as_struct.state = kRunnable;
-      // CAS the value without a memory barrier, that occurred in the lock above.
-      done = android_atomic_cas(old_state_and_flags.as_int, new_state_and_flags.as_int,
-                                &tls32_.state_and_flags.as_int) == 0;
+      // CAS the value without a memory ordering as that is given by the lock acquisition above.
+      done =
+          tls32_.state_and_flags.as_atomic_int.CompareExchangeWeakRelaxed(old_state_and_flags.as_int,
+                                                                          new_state_and_flags.as_int);
     }
     if (UNLIKELY(!done)) {
       // Failed to transition to Runnable. Release shared mutator_lock_ access and try again.