On Tue, Nov 11, 2014 at 10:12:01AM +0100, Daniel Vetter wrote:
> Motivated by the per-plane locking I've gone through all the get*
> ioctls and reduced the locking to the bare minimum required.
>
> v2: Rebase and make it compile ...
>
> Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx>
Just a couple nits.
> ---
> drivers/gpu/drm/drm_crtc.c | 46 ++++++++++++++++++----------------------------
> 1 file changed, 18 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
> index 3652ed8dda80..8850f32994e3 100644
> --- a/drivers/gpu/drm/drm_crtc.c
> +++ b/drivers/gpu/drm/drm_crtc.c
> @@ -1743,7 +1743,9 @@ int drm_mode_getresources(struct drm_device *dev, void *data,
> card_res->count_fbs = fb_count;
> mutex_unlock(&file_priv->fbs_lock);
>
> - drm_modeset_lock_all(dev);
> + /* mode_config.mutex protects the connector list against e.g. DP MST
> + * connector hot-adding. CRTC/Plane lists are invariant. */
> + mutex_lock(&dev->mode_config.mutex);
> if (!drm_is_primary_client(file_priv)) {
>
> mode_group = NULL;
> @@ -1863,7 +1865,7 @@ int drm_mode_getresources(struct drm_device *dev, void *data,
> card_res->count_connectors, card_res->count_encoders);
>
> out:
> - drm_modeset_unlock_all(dev);
> + mutex_unlock(&dev->mode_config.mutex);
> return ret;
> }
>
> @@ -1890,14 +1892,11 @@ int drm_mode_getcrtc(struct drm_device *dev,
> if (!drm_core_check_feature(dev, DRIVER_MODESET))
> return -EINVAL;
>
> - drm_modeset_lock_all(dev);
> -
> crtc = drm_crtc_find(dev, crtc_resp->crtc_id);
> - if (!crtc) {
> - ret = -ENOENT;
> - goto out;
> - }
> + if (!crtc)
> + return -ENOENT;
>
> + drm_modeset_lock_crtc(crtc, crtc->primary);
> crtc_resp->x = crtc->x;
> crtc_resp->y = crtc->y;
> crtc_resp->gamma_size = crtc->gamma_size;
> @@ -1914,9 +1913,8 @@ int drm_mode_getcrtc(struct drm_device *dev,
> } else {
> crtc_resp->mode_valid = 0;
> }
> + drm_modeset_unlock_crtc(crtc);
>
> -out:
> - drm_modeset_unlock_all(dev);
> return ret;
> }
>
> @@ -2100,24 +2098,22 @@ int drm_mode_getencoder(struct drm_device *dev, void *data,
> if (!drm_core_check_feature(dev, DRIVER_MODESET))
> return -EINVAL;
>
> - drm_modeset_lock_all(dev);
> encoder = drm_encoder_find(dev, enc_resp->encoder_id);
> - if (!encoder) {
> - ret = -ENOENT;
> - goto out;
> - }
> + if (!encoder)
> + return -ENOENT;
>
> + drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
> if (encoder->crtc)
> enc_resp->crtc_id = encoder->crtc->base.id;
> else
> enc_resp->crtc_id = 0;
> + drm_modeset_unlock(&dev->mode_config.connection_mutex);
> +
> enc_resp->encoder_type = encoder->encoder_type;
> enc_resp->encoder_id = encoder->base.id;
> enc_resp->possible_crtcs = encoder->possible_crtcs;
> enc_resp->possible_clones = encoder->possible_clones;
>
> -out:
> - drm_modeset_unlock_all(dev);
> return ret;
> }
>
> @@ -2147,7 +2143,6 @@ int drm_mode_getplane_res(struct drm_device *dev, void *data,
> if (!drm_core_check_feature(dev, DRIVER_MODESET))
> return -EINVAL;
>
> - drm_modeset_lock_all(dev);
> config = &dev->mode_config;
I'd feel better if you added a comment here similar to the one above
explaining that the plane_list cannot change and thus accessing it does not
require locking config->mutex.
>
> if (file_priv->universal_planes)
> @@ -2182,7 +2177,6 @@ int drm_mode_getplane_res(struct drm_device *dev, void *data,
> plane_resp->count_planes = num_planes;
>
> out:
I think you can just remove this label entirely and return straight from the
failure cases.
> - drm_modeset_unlock_all(dev);
> return ret;
> }
>
> @@ -2210,13 +2204,11 @@ int drm_mode_getplane(struct drm_device *dev, void *data,
> if (!drm_core_check_feature(dev, DRIVER_MODESET))
> return -EINVAL;
>
> - drm_modeset_lock_all(dev);
> plane = drm_plane_find(dev, plane_resp->plane_id);
> - if (!plane) {
> - ret = -ENOENT;
> - goto out;
> - }
> + if (!plane)
> + return -ENOENT;
>
> + drm_modeset_lock(&plane->mutex, NULL);
> if (plane->crtc)
> plane_resp->crtc_id = plane->crtc->base.id;
> else
> @@ -2226,6 +2218,7 @@ int drm_mode_getplane(struct drm_device *dev, void *data,
> plane_resp->fb_id = plane->fb->base.id;
> else
> plane_resp->fb_id = 0;
> + drm_modeset_unlock(&plane->mutex);
>
> plane_resp->plane_id = plane->base.id;
> plane_resp->possible_crtcs = plane->possible_crtcs;
> @@ -2241,14 +2234,11 @@ int drm_mode_getplane(struct drm_device *dev, void *data,
> if (copy_to_user(format_ptr,
> plane->format_types,
> sizeof(uint32_t) * plane->format_count)) {
> - ret = -EFAULT;
> - goto out;
> + return -EFAULT;
> }
> }
> plane_resp->count_format_types = plane->format_count;
>
> -out:
> - drm_modeset_unlock_all(dev);
> return ret;
> }
>
> --
> 2.1.1
>
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
http://lists.freedesktop.org/mailman/listinfo/dri-devel
