[PATCH 3/5] drm/msm: Remove call to reservation_object_test_signaled_rcu before wait

[Sumit Semwal]

Hi Chris,

On 11 August 2016 at 20:16, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> Since fence_wait_timeout_reservation_object_wait_timeout_rcu() with a
> timeout of 0 becomes reservation_object_test_signaled_rcu(), we do not
> need to handle such conversion in the caller. The only challenge are
> those callers that wish to differentiate the error code between the
> nonblocking busy check and potentially blocking wait.
>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Rob Clark <robdclark at gmail.com>
> ---
>  drivers/gpu/drm/msm/msm_gem.c | 22 ++++++++++------------
>  1 file changed, 10 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
> index 6cd4af443139..ab07eb6de25e 100644
> --- a/drivers/gpu/drm/msm/msm_gem.c
> +++ b/drivers/gpu/drm/msm/msm_gem.c
> @@ -584,18 +584,16 @@ int msm_gem_cpu_prep(struct drm_gem_object *obj, uint32_t op, ktime_t *timeout)
>  {
>         struct msm_gem_object *msm_obj = to_msm_bo(obj);
>         bool write = !!(op & MSM_PREP_WRITE);
> -
> -       if (op & MSM_PREP_NOSYNC) {
> -               if (!reservation_object_test_signaled_rcu(msm_obj->resv, write))
> -                       return -EBUSY;
> -       } else {
> -               int ret;
> -
> -               ret = reservation_object_wait_timeout_rcu(msm_obj->resv, write,
> -                               true, timeout_to_jiffies(timeout));
> -               if (ret <= 0)
> -                       return ret == 0 ? -ETIMEDOUT : ret;
> -       }
> +       unsigned long remain =
> +               op & MSG_PREP_NOSYNC ? 0 : timeout_to_jiffies(timeout);
> +       long ret;
> +
> +       ret = reservation_object_wait_timeout_rcu(msm_obj->resv, write,
> +                                                 true,  remain);
> +       if (ret == 0)
> +               return remain == 9 ? -EBUSY : -ETIMEDOUT;

Am sure this must be a typo - 0 instead of 9?

> +       else if (ret < 0)
> +               return ret;
>
>         /* TODO cache maintenance */
>
> --
> 2.8.1
>
> _______________________________________________
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel