[Intel-gfx] [PATCH 7/7] drm/atomic: Reduce setplane locking
Daniel Vetter
daniel at ffwll.ch
Tue Nov 19 10:47:11 UTC 2019
On Fri, Nov 15, 2019 at 09:42:04PM +0200, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
>
> Currently setplane grabs all modeset locks, which seems a bit
> excessive. Let's reduce that to just the locks we really need
> on atomic drivers. For non-atomic drivers let's stick to the
> current scheme for now.
>
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> ---
> drivers/gpu/drm/drm_plane.c | 56 +++++++++++++++++++------------------
> 1 file changed, 29 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c
> index ef0cc33b43ce..e40d8a93294b 100644
> --- a/drivers/gpu/drm/drm_plane.c
> +++ b/drivers/gpu/drm/drm_plane.c
> @@ -680,10 +680,14 @@ static int __setplane_internal(struct drm_plane *plane,
> uint32_t src_w, uint32_t src_h,
> struct drm_modeset_acquire_ctx *ctx)
> {
> - int ret = 0;
> + int ret;
>
> WARN_ON(drm_drv_uses_atomic_modeset(plane->dev));
>
> + ret = drm_modeset_lock_all_ctx(plane->dev, ctx);
> + if (ret)
> + return ret;
There's pre-nv50 nouveau and shmob which have planes and aren't atomic (if
I checked correctly), so we could probably forgo this, but also feels
like totally not worth the audit trouble.
Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> +
> /* No fb means shut it down */
> if (!fb) {
> plane->old_fb = plane->fb;
> @@ -767,32 +771,24 @@ static int setplane_internal(struct drm_plane *plane,
> uint32_t crtc_w, uint32_t crtc_h,
> /* src_{x,y,w,h} values are 16.16 fixed point */
> uint32_t src_x, uint32_t src_y,
> - uint32_t src_w, uint32_t src_h)
> + uint32_t src_w, uint32_t src_h,
> + struct drm_modeset_acquire_ctx *ctx)
> {
> - struct drm_modeset_acquire_ctx ctx;
> - int ret;
> -
> - DRM_MODESET_LOCK_ALL_BEGIN(plane->dev, ctx,
> - DRM_MODESET_ACQUIRE_INTERRUPTIBLE, ret);
> -
> if (drm_drv_uses_atomic_modeset(plane->dev))
> - ret = __setplane_atomic(plane, crtc, fb,
> - crtc_x, crtc_y, crtc_w, crtc_h,
> - src_x, src_y, src_w, src_h, &ctx);
> + return __setplane_atomic(plane, crtc, fb,
> + crtc_x, crtc_y, crtc_w, crtc_h,
> + src_x, src_y, src_w, src_h, ctx);
> else
> - ret = __setplane_internal(plane, crtc, fb,
> - crtc_x, crtc_y, crtc_w, crtc_h,
> - src_x, src_y, src_w, src_h, &ctx);
> -
> - DRM_MODESET_LOCK_ALL_END(ctx, ret);
> -
> - return ret;
> + return __setplane_internal(plane, crtc, fb,
> + crtc_x, crtc_y, crtc_w, crtc_h,
> + src_x, src_y, src_w, src_h, ctx);
> }
>
> int drm_mode_setplane(struct drm_device *dev, void *data,
> struct drm_file *file_priv)
> {
> struct drm_mode_set_plane *plane_req = data;
> + struct drm_modeset_acquire_ctx ctx;
> struct drm_plane *plane;
> struct drm_crtc *crtc = NULL;
> struct drm_framebuffer *fb = NULL;
> @@ -829,11 +825,22 @@ int drm_mode_setplane(struct drm_device *dev, void *data,
> }
> }
>
> + drm_modeset_acquire_init(&ctx, DRM_MODESET_ACQUIRE_INTERRUPTIBLE);
> +
> +retry:
> ret = setplane_internal(plane, crtc, fb,
> plane_req->crtc_x, plane_req->crtc_y,
> plane_req->crtc_w, plane_req->crtc_h,
> plane_req->src_x, plane_req->src_y,
> - plane_req->src_w, plane_req->src_h);
> + plane_req->src_w, plane_req->src_h, &ctx);
> + if (ret == -EDEADLK) {
> + ret = drm_modeset_backoff(&ctx);
> + if (!ret)
> + goto retry;
> + }
> +
> + drm_modeset_drop_locks(&ctx);
> + drm_modeset_acquire_fini(&ctx);
>
> if (fb)
> drm_framebuffer_put(fb);
> @@ -907,14 +914,9 @@ static int drm_mode_cursor_universal(struct drm_crtc *crtc,
> src_h = fb->height << 16;
> }
>
> - if (drm_drv_uses_atomic_modeset(dev))
> - ret = __setplane_atomic(plane, crtc, fb,
> - crtc_x, crtc_y, crtc_w, crtc_h,
> - 0, 0, src_w, src_h, ctx);
> - else
> - ret = __setplane_internal(plane, crtc, fb,
> - crtc_x, crtc_y, crtc_w, crtc_h,
> - 0, 0, src_w, src_h, ctx);
> + ret = setplane_internal(plane, crtc, fb,
> + crtc_x, crtc_y, crtc_w, crtc_h,
> + 0, 0, src_w, src_h, ctx);
>
> if (fb)
> drm_framebuffer_put(fb);
> --
> 2.23.0
>
> _______________________________________________
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
More information about the Intel-gfx
mailing list