drm/atomic-helper: remove backoff hack from disable/update_plane

We can now properly retry at the top level, yay!

v2: Also remove the temporary acquire_ctx hack again, no longer
needed!

Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170322215058.8671-6-daniel.vetter@ffwll.ch

2 files changed, 2 insertions, 49 deletions

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 6096233a740c..cc6e2772b32f 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -2101,8 +2101,7 @@ int drm_atomic_helper_update_plane(struct drm_plane *plane,
         if (!state)
                 return -ENOMEM;
 
-        state->acquire_ctx = drm_modeset_legacy_acquire_ctx(crtc);
-retry:
+        state->acquire_ctx = ctx;
         plane_state = drm_atomic_get_plane_state(state, plane);
         if (IS_ERR(plane_state)) {
                 ret = PTR_ERR(plane_state);
@@ -2127,24 +2126,8 @@ retry:
 
         ret = drm_atomic_commit(state);
 fail:
-        if (ret == -EDEADLK)
-                goto backoff;
-
         drm_atomic_state_put(state);
         return ret;
-
-backoff:
-        drm_atomic_state_clear(state);
-        drm_atomic_legacy_backoff(state);
-
-        /*
-         * Someone might have exchanged the framebuffer while we dropped locks
-         * in the backoff code. We need to fix up the fb refcount tracking the
-         * core does for us.
-         */
-        plane->old_fb = plane->fb;
-
-        goto retry;
 }
 EXPORT_SYMBOL(drm_atomic_helper_update_plane);
 
@@ -2165,23 +2148,11 @@ int drm_atomic_helper_disable_plane(struct drm_plane *plane,
         struct drm_plane_state *plane_state;
         int ret = 0;
 
-        /*
-         * FIXME: Without plane->crtc set we can't get at the implicit legacy
-         * acquire context. The real fix will be to wire the acquire ctx through
-         * everywhere we need it, but meanwhile prevent chaos by just skipping
-         * this noop. The critical case is the cursor ioctls which a) only grab
-         * crtc/cursor-plane locks (so we need the crtc to get at the right
-         * acquire context) and b) can try to disable the plane multiple times.
-         */
-        if (!plane->crtc)
-                return 0;
-
         state = drm_atomic_state_alloc(plane->dev);
         if (!state)
                 return -ENOMEM;
 
-        state->acquire_ctx = drm_modeset_legacy_acquire_ctx(plane->crtc);
-retry:
+        state->acquire_ctx = ctx;
         plane_state = drm_atomic_get_plane_state(state, plane);
         if (IS_ERR(plane_state)) {
                 ret = PTR_ERR(plane_state);
@@ -2197,24 +2168,8 @@ retry:
 
         ret = drm_atomic_commit(state);
 fail:
-        if (ret == -EDEADLK)
-                goto backoff;
-
         drm_atomic_state_put(state);
         return ret;
-
-backoff:
-        drm_atomic_state_clear(state);
-        drm_atomic_legacy_backoff(state);
-
-        /*
-         * Someone might have exchanged the framebuffer while we dropped locks
-         * in the backoff code. We need to fix up the fb refcount tracking the
-         * core does for us.
-         */
-        plane->old_fb = plane->fb;
-
-        goto retry;
 }
 EXPORT_SYMBOL(drm_atomic_helper_disable_plane);
 
diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c
index 526e74b548b2..8535dc17db7e 100644
--- a/drivers/gpu/drm/drm_plane.c
+++ b/drivers/gpu/drm/drm_plane.c
@@ -554,7 +554,6 @@ retry:
         ret = drm_modeset_lock_all_ctx(plane->dev, &ctx);
         if (ret)
                 goto fail;
-        plane->dev->mode_config.acquire_ctx = &ctx;
         ret = __setplane_internal(plane, crtc, fb,
                                   crtc_x, crtc_y, crtc_w, crtc_h,
                                   src_x, src_y, src_w, src_h, &ctx);
@@ -649,7 +648,6 @@ retry:
         ret = drm_modeset_lock(&crtc->cursor->mutex, &ctx);
         if (ret)
                 goto fail;
-        crtc->acquire_ctx = &ctx;
 
         /*
          * Obtain fb we'll be using (either new or existing) and take an extra