[PATCH v1 11/18] thread: add tsan annotations to QemuSpin

["Alex Bennée" <alex.bennee@linaro.org>]

From: "Emilio G. Cota" <cota@braap.org>

Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Robert Foley <robert.foley@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200609200738.445-9-robert.foley@linaro.org>
---
 include/qemu/thread.h | 39 ++++++++++++++++++++++++++++++++++++---
 1 file changed, 36 insertions(+), 3 deletions(-)

diff --git a/include/qemu/thread.h b/include/qemu/thread.h
index e50a0738897..43fc094b963 100644
--- a/include/qemu/thread.h
+++ b/include/qemu/thread.h
@@ -206,6 +206,10 @@ void qemu_thread_atexit_add(struct Notifier *notifier);
  */
 void qemu_thread_atexit_remove(struct Notifier *notifier);
 
+#ifdef CONFIG_TSAN
+#include <sanitizer/tsan_interface.h>
+#endif
+
 struct QemuSpin {
     int value;
 };
@@ -213,23 +217,46 @@ struct QemuSpin {
 static inline void qemu_spin_init(QemuSpin *spin)
 {
     __sync_lock_release(&spin->value);
+#ifdef CONFIG_TSAN
+    __tsan_mutex_create(spin, __tsan_mutex_not_static);
+#endif
 }
 
-static inline void qemu_spin_destroy(QemuSpin *spin)
-{ }
+/* const parameter because the only purpose here is the TSAN annotation */
+static inline void qemu_spin_destroy(const QemuSpin *spin)
+{
+#ifdef CONFIG_TSAN
+    __tsan_mutex_destroy((void *)spin, __tsan_mutex_not_static);
+#endif
+}
 
 static inline void qemu_spin_lock(QemuSpin *spin)
 {
+#ifdef CONFIG_TSAN
+    __tsan_mutex_pre_lock(spin, 0);
+#endif
     while (unlikely(__sync_lock_test_and_set(&spin->value, true))) {
         while (atomic_read(&spin->value)) {
             cpu_relax();
         }
     }
+#ifdef CONFIG_TSAN
+    __tsan_mutex_post_lock(spin, 0, 0);
+#endif
 }
 
 static inline bool qemu_spin_trylock(QemuSpin *spin)
 {
-    return __sync_lock_test_and_set(&spin->value, true);
+#ifdef CONFIG_TSAN
+    __tsan_mutex_pre_lock(spin, __tsan_mutex_try_lock);
+#endif
+    bool busy = __sync_lock_test_and_set(&spin->value, true);
+#ifdef CONFIG_TSAN
+    unsigned flags = __tsan_mutex_try_lock;
+    flags |= busy ? __tsan_mutex_try_lock_failed : 0;
+    __tsan_mutex_post_lock(spin, flags, 0);
+#endif
+    return busy;
 }
 
 static inline bool qemu_spin_locked(QemuSpin *spin)
@@ -239,7 +266,13 @@ static inline bool qemu_spin_locked(QemuSpin *spin)
 
 static inline void qemu_spin_unlock(QemuSpin *spin)
 {
+#ifdef CONFIG_TSAN
+    __tsan_mutex_pre_unlock(spin, 0);
+#endif
     __sync_lock_release(&spin->value);
+#ifdef CONFIG_TSAN
+    __tsan_mutex_post_unlock(spin, 0);
+#endif
 }
 
 struct QemuLockCnt {
-- 
2.20.1