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
diff --git a/runtime/atomic.h b/runtime/atomic.h
index ed83a33..5cfdbcc 100644
--- a/runtime/atomic.h
+++ b/runtime/atomic.h
@@ -415,7 +415,7 @@
};
template<typename T>
-class Atomic {
+class PACKED(sizeof(T)) Atomic {
private:
COMPILE_ASSERT(sizeof(T) <= 4 || sizeof(T) == 8, bad_atomic_arg);
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 @@
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 @@
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.
diff --git a/runtime/thread.cc b/runtime/thread.cc
index d60fb49..4985583 100644
--- a/runtime/thread.cc
+++ b/runtime/thread.cc
@@ -34,8 +34,6 @@
#include "base/mutex.h"
#include "class_linker.h"
#include "class_linker-inl.h"
-#include "cutils/atomic.h"
-#include "cutils/atomic-inline.h"
#include "debugger.h"
#include "dex_file-inl.h"
#include "entrypoints/entrypoint_utils.h"
diff --git a/runtime/thread.h b/runtime/thread.h
index 7cd86de..0640b38 100644
--- a/runtime/thread.h
+++ b/runtime/thread.h
@@ -24,6 +24,7 @@
#include <memory>
#include <string>
+#include "atomic.h"
#include "base/macros.h"
#include "base/mutex.h"
#include "entrypoints/interpreter/interpreter_entrypoints.h"
@@ -864,6 +865,7 @@
// change to Runnable as a GC or other operation is in progress.
volatile uint16_t state;
} as_struct;
+ AtomicInteger as_atomic_int;
volatile int32_t as_int;
private:
@@ -871,6 +873,7 @@
// See http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47409
DISALLOW_COPY_AND_ASSIGN(StateAndFlags);
};
+ COMPILE_ASSERT(sizeof(StateAndFlags) == sizeof(int32_t), weird_state_and_flags_size);
static void ThreadExitCallback(void* arg);