[PATCH 5/6] reservation: add support for fences to enable cross-device synchronisation

[Rob Clark]

On Mon, Feb 17, 2014 at 10:58 AM, Maarten Lankhorst
<maarten.lankhorst at canonical.com> wrote:
> Signed-off-by: Maarten Lankhorst <maarten.lankhorst at canonical.com>

Reviewed-by: Rob Clark <robdclark at gmail.com>


> ---
>  include/linux/reservation.h |   18 +++++++++++++++++-
>  1 file changed, 17 insertions(+), 1 deletion(-)
>
> diff --git a/include/linux/reservation.h b/include/linux/reservation.h
> index 813dae960ebd..92c4851b5a39 100644
> --- a/include/linux/reservation.h
> +++ b/include/linux/reservation.h
> @@ -6,7 +6,7 @@
>   * Copyright (C) 2012 Texas Instruments
>   *
>   * Authors:
> - * Rob Clark <rob.clark at linaro.org>
> + * Rob Clark <robdclark at gmail.com>
>   * Maarten Lankhorst <maarten.lankhorst at canonical.com>
>   * Thomas Hellstrom <thellstrom-at-vmware-dot-com>
>   *
> @@ -40,22 +40,38 @@
>  #define _LINUX_RESERVATION_H
>
>  #include <linux/ww_mutex.h>
> +#include <linux/fence.h>
>
>  extern struct ww_class reservation_ww_class;
>
>  struct reservation_object {
>         struct ww_mutex lock;
> +
> +       struct fence *fence_excl;
> +       struct fence **fence_shared;
> +       u32 fence_shared_count, fence_shared_max;
>  };
>
>  static inline void
>  reservation_object_init(struct reservation_object *obj)
>  {
>         ww_mutex_init(&obj->lock, &reservation_ww_class);
> +
> +       obj->fence_shared_count = obj->fence_shared_max = 0;
> +       obj->fence_shared = NULL;
> +       obj->fence_excl = NULL;
>  }
>
>  static inline void
>  reservation_object_fini(struct reservation_object *obj)
>  {
> +       int i;
> +
> +       if (obj->fence_excl)
> +               fence_put(obj->fence_excl);
> +       for (i = 0; i < obj->fence_shared_count; ++i)
> +               fence_put(obj->fence_shared[i]);
> +
>         ww_mutex_destroy(&obj->lock);
>  }
>
>