Re: [PATCH v1 08/12] thread: add tsan annotations to QemuSpin

[Alex Bennée]

Robert Foley <robert.foley@linaro.org> writes:

> 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>

> ---
>  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 e50a073889..43fc094b96 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 {


-- 
Alex Bennée