[Intel-gfx] [PATCH v8 02/12] drm/i915: Add i915 perf infrastructure

[Matthew Auld]

> +/* Note we copy the properties from userspace outside of the i915 perf
> + * mutex to avoid an awkward lockdep with mmap_sem.
> + *
> + * Note this function only validates properties in isolation it doesn't
> + * validate that the combination of properties makes sense or that all
> + * properties necessary for a particular kind of stream have been set.
> + */
> +static int read_properties_unlocked(struct drm_i915_private *dev_priv,
> +                                   u64 __user *uprops,
> +                                   u32 n_props,
> +                                   struct perf_open_properties *props)
> +{
> +       u64 __user *uprop = uprops;
> +       int i;
> +
> +       memset(props, 0, sizeof(struct perf_open_properties));
> +
> +       if (!n_props) {
> +               DRM_ERROR("No i915 perf properties given");
> +               return -EINVAL;
> +       }
> +
> +       if (n_props > DRM_I915_PERF_PROP_MAX) {
Ah but DRM_I915_PERF_PROP_MAX is not a property itself.