drm: Add reference counting to drm_atomic_state
authorChris Wilson <chris@chris-wilson.co.uk>
Fri, 14 Oct 2016 12:18:18 +0000 (13:18 +0100)
committerDaniel Vetter <daniel.vetter@ffwll.ch>
Mon, 17 Oct 2016 06:19:57 +0000 (08:19 +0200)
drm_atomic_state has a complicated single owner model that tracks the
single reference from allocation through to destruction on another
thread - or perhaps on a local error path. We can simplify this tracking
by using reference counting (at a cost of a few more atomics). This is
even more beneficial when the lifetime of the state becomes more
convoluted than being passed to a single worker thread for the commit.

v2: Double check !intel atomic_commit functions for missing gets
v3: Update kerneldocs

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161014121833.439-27-chris@chris-wilson.co.uk
18 files changed:
drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c
drivers/gpu/drm/drm_atomic.c
drivers/gpu/drm/drm_atomic_helper.c
drivers/gpu/drm/drm_fb_helper.c
drivers/gpu/drm/exynos/exynos_drm_drv.c
drivers/gpu/drm/i915/i915_debugfs.c
drivers/gpu/drm/i915/intel_display.c
drivers/gpu/drm/i915/intel_sprite.c
drivers/gpu/drm/mediatek/mtk_drm_drv.c
drivers/gpu/drm/msm/msm_atomic.c
drivers/gpu/drm/omapdrm/omap_drv.c
drivers/gpu/drm/rcar-du/rcar_du_kms.c
drivers/gpu/drm/sti/sti_drv.c
drivers/gpu/drm/tegra/drm.c
drivers/gpu/drm/tilcdc/tilcdc_drv.c
drivers/gpu/drm/vc4/vc4_kms.c
include/drm/drm_atomic.h
include/drm/drm_plane.h

index 5f484310bee99c4ba5bbd986f47223893756db77..9f6222895212606c97ef5a7a98092790f587832a 100644 (file)
@@ -464,7 +464,7 @@ atmel_hlcdc_dc_atomic_complete(struct atmel_hlcdc_dc_commit *commit)
 
        drm_atomic_helper_cleanup_planes(dev, old_state);
 
-       drm_atomic_state_free(old_state);
+       drm_atomic_state_put(old_state);
 
        /* Complete the commit, wake up any waiter. */
        spin_lock(&dc->commit.wait.lock);
@@ -521,6 +521,7 @@ static int atmel_hlcdc_dc_atomic_commit(struct drm_device *dev,
        /* Swap the state, this is the point of no return. */
        drm_atomic_helper_swap_state(state, true);
 
+       drm_atomic_state_get(state);
        if (async)
                queue_work(dc->wq, &commit->work);
        else
index 23739609427d86b9cd64d81ddad719bf5fc2bd78..5dd70540219c18fbd6114ed3addcec84dbefa133 100644 (file)
@@ -74,6 +74,8 @@ EXPORT_SYMBOL(drm_atomic_state_default_release);
 int
 drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state)
 {
+       kref_init(&state->ref);
+
        /* TODO legacy paths should maybe do a better job about
         * setting this appropriately?
         */
@@ -215,22 +217,16 @@ void drm_atomic_state_clear(struct drm_atomic_state *state)
 EXPORT_SYMBOL(drm_atomic_state_clear);
 
 /**
- * drm_atomic_state_free - free all memory for an atomic state
- * @state: atomic state to deallocate
+ * __drm_atomic_state_free - free all memory for an atomic state
+ * @ref: This atomic state to deallocate
  *
  * This frees all memory associated with an atomic state, including all the
  * per-object state for planes, crtcs and connectors.
  */
-void drm_atomic_state_free(struct drm_atomic_state *state)
+void __drm_atomic_state_free(struct kref *ref)
 {
-       struct drm_device *dev;
-       struct drm_mode_config *config;
-
-       if (!state)
-               return;
-
-       dev = state->dev;
-       config = &dev->mode_config;
+       struct drm_atomic_state *state = container_of(ref, typeof(*state), ref);
+       struct drm_mode_config *config = &state->dev->mode_config;
 
        drm_atomic_state_clear(state);
 
@@ -243,7 +239,7 @@ void drm_atomic_state_free(struct drm_atomic_state *state)
                kfree(state);
        }
 }
-EXPORT_SYMBOL(drm_atomic_state_free);
+EXPORT_SYMBOL(__drm_atomic_state_free);
 
 /**
  * drm_atomic_get_crtc_state - get crtc state
@@ -1742,7 +1738,7 @@ retry:
        if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) {
                /*
                 * Unlike commit, check_only does not clean up state.
-                * Below we call drm_atomic_state_free for it.
+                * Below we call drm_atomic_state_put for it.
                 */
                ret = drm_atomic_check_only(state);
        } else if (arg->flags & DRM_MODE_ATOMIC_NONBLOCK) {
@@ -1775,8 +1771,7 @@ out:
                goto retry;
        }
 
-       if (ret || arg->flags & DRM_MODE_ATOMIC_TEST_ONLY)
-               drm_atomic_state_free(state);
+       drm_atomic_state_put(state);
 
        drm_modeset_drop_locks(&ctx);
        drm_modeset_acquire_fini(&ctx);
index 36f83fe5ec462fab65f958fa574d9b412c891854..07b432f43b98002fab481d55178138a02dbea4dd 100644 (file)
@@ -1208,7 +1208,7 @@ static void commit_tail(struct drm_atomic_state *state)
 
        drm_atomic_helper_commit_cleanup_done(state);
 
-       drm_atomic_state_free(state);
+       drm_atomic_state_put(state);
 }
 
 static void commit_work(struct work_struct *work)
@@ -1290,6 +1290,7 @@ int drm_atomic_helper_commit(struct drm_device *dev,
         * make sure work items don't artifically stall on each another.
         */
 
+       drm_atomic_state_get(state);
        if (nonblock)
                queue_work(system_unbound_wq, &state->commit_work);
        else
@@ -1591,7 +1592,7 @@ EXPORT_SYMBOL(drm_atomic_helper_commit_hw_done);
  *
  * This signals completion of the atomic update @state, including any cleanup
  * work. If used, it must be called right before calling
- * drm_atomic_state_free().
+ * drm_atomic_state_put().
  *
  * This is part of the atomic helper support for nonblocking commits, see
  * drm_atomic_helper_setup_commit() for an overview.
@@ -2114,18 +2115,13 @@ retry:
                state->legacy_cursor_update = true;
 
        ret = drm_atomic_commit(state);
-       if (ret != 0)
-               goto fail;
-
-       /* Driver takes ownership of state on successful commit. */
-       return 0;
 fail:
        if (ret == -EDEADLK)
                goto backoff;
 
-       drm_atomic_state_free(state);
-
+       drm_atomic_state_put(state);
        return ret;
+
 backoff:
        drm_atomic_state_clear(state);
        drm_atomic_legacy_backoff(state);
@@ -2187,18 +2183,13 @@ retry:
                goto fail;
 
        ret = drm_atomic_commit(state);
-       if (ret != 0)
-               goto fail;
-
-       /* Driver takes ownership of state on successful commit. */
-       return 0;
 fail:
        if (ret == -EDEADLK)
                goto backoff;
 
-       drm_atomic_state_free(state);
-
+       drm_atomic_state_put(state);
        return ret;
+
 backoff:
        drm_atomic_state_clear(state);
        drm_atomic_legacy_backoff(state);
@@ -2327,18 +2318,13 @@ retry:
                goto fail;
 
        ret = drm_atomic_commit(state);
-       if (ret != 0)
-               goto fail;
-
-       /* Driver takes ownership of state on successful commit. */
-       return 0;
 fail:
        if (ret == -EDEADLK)
                goto backoff;
 
-       drm_atomic_state_free(state);
-
+       drm_atomic_state_put(state);
        return ret;
+
 backoff:
        drm_atomic_state_clear(state);
        drm_atomic_legacy_backoff(state);
@@ -2480,11 +2466,8 @@ int drm_atomic_helper_disable_all(struct drm_device *dev,
        }
 
        err = drm_atomic_commit(state);
-
 free:
-       if (err < 0)
-               drm_atomic_state_free(state);
-
+       drm_atomic_state_put(state);
        return err;
 }
 EXPORT_SYMBOL(drm_atomic_helper_disable_all);
@@ -2535,7 +2518,7 @@ retry:
 
        err = drm_atomic_helper_disable_all(dev, &ctx);
        if (err < 0) {
-               drm_atomic_state_free(state);
+               drm_atomic_state_put(state);
                state = ERR_PTR(err);
                goto unlock;
        }
@@ -2624,18 +2607,13 @@ retry:
                goto fail;
 
        ret = drm_atomic_commit(state);
-       if (ret != 0)
-               goto fail;
-
-       /* Driver takes ownership of state on successful commit. */
-       return 0;
 fail:
        if (ret == -EDEADLK)
                goto backoff;
 
-       drm_atomic_state_free(state);
-
+       drm_atomic_state_put(state);
        return ret;
+
 backoff:
        drm_atomic_state_clear(state);
        drm_atomic_legacy_backoff(state);
@@ -2684,18 +2662,13 @@ retry:
                goto fail;
 
        ret = drm_atomic_commit(state);
-       if (ret != 0)
-               goto fail;
-
-       /* Driver takes ownership of state on successful commit. */
-       return 0;
 fail:
        if (ret == -EDEADLK)
                goto backoff;
 
-       drm_atomic_state_free(state);
-
+       drm_atomic_state_put(state);
        return ret;
+
 backoff:
        drm_atomic_state_clear(state);
        drm_atomic_legacy_backoff(state);
@@ -2744,18 +2717,13 @@ retry:
                goto fail;
 
        ret = drm_atomic_commit(state);
-       if (ret != 0)
-               goto fail;
-
-       /* Driver takes ownership of state on successful commit. */
-       return 0;
 fail:
        if (ret == -EDEADLK)
                goto backoff;
 
-       drm_atomic_state_free(state);
-
+       drm_atomic_state_put(state);
        return ret;
+
 backoff:
        drm_atomic_state_clear(state);
        drm_atomic_legacy_backoff(state);
@@ -2828,18 +2796,13 @@ retry:
        }
 
        ret = drm_atomic_nonblocking_commit(state);
-       if (ret != 0)
-               goto fail;
-
-       /* Driver takes ownership of state on successful commit. */
-       return 0;
 fail:
        if (ret == -EDEADLK)
                goto backoff;
 
-       drm_atomic_state_free(state);
-
+       drm_atomic_state_put(state);
        return ret;
+
 backoff:
        drm_atomic_state_clear(state);
        drm_atomic_legacy_backoff(state);
@@ -2915,19 +2878,14 @@ retry:
        crtc_state->active = active;
 
        ret = drm_atomic_commit(state);
-       if (ret != 0)
-               goto fail;
-
-       /* Driver takes ownership of state on successful commit. */
-       return 0;
 fail:
        if (ret == -EDEADLK)
                goto backoff;
 
        connector->dpms = old_mode;
-       drm_atomic_state_free(state);
-
+       drm_atomic_state_put(state);
        return ret;
+
 backoff:
        drm_atomic_state_clear(state);
        drm_atomic_legacy_backoff(state);
@@ -3334,7 +3292,7 @@ drm_atomic_helper_duplicate_state(struct drm_device *dev,
 
 free:
        if (err < 0) {
-               drm_atomic_state_free(state);
+               drm_atomic_state_put(state);
                state = ERR_PTR(err);
        }
 
@@ -3449,22 +3407,14 @@ retry:
                goto fail;
 
        ret = drm_atomic_commit(state);
-       if (ret)
-               goto fail;
-
-       /* Driver takes ownership of state on successful commit. */
-
-       drm_property_unreference_blob(blob);
-
-       return 0;
 fail:
        if (ret == -EDEADLK)
                goto backoff;
 
-       drm_atomic_state_free(state);
+       drm_atomic_state_put(state);
        drm_property_unreference_blob(blob);
-
        return ret;
+
 backoff:
        drm_atomic_state_clear(state);
        drm_atomic_legacy_backoff(state);
index 03414bde1f152637a7ed6002ed8a88e30611fec8..22d4f0e221013e81862c4879c7dd0822353e50ce 100644 (file)
@@ -367,9 +367,7 @@ fail:
        if (ret == -EDEADLK)
                goto backoff;
 
-       if (ret != 0)
-               drm_atomic_state_free(state);
-
+       drm_atomic_state_put(state);
        return ret;
 
 backoff:
@@ -1361,16 +1359,13 @@ retry:
        info->var.xoffset = var->xoffset;
        info->var.yoffset = var->yoffset;
 
-
 fail:
        drm_atomic_clean_old_fb(dev, plane_mask, ret);
 
        if (ret == -EDEADLK)
                goto backoff;
 
-       if (ret != 0)
-               drm_atomic_state_free(state);
-
+       drm_atomic_state_put(state);
        return ret;
 
 backoff:
index def78c8c1780a90ef8a8354770a3618276a506da..4a21a745c373c323d0da1db9c268eb69fb7e5400 100644 (file)
@@ -69,7 +69,7 @@ static void exynos_atomic_commit_complete(struct exynos_atomic_commit *commit)
 
        drm_atomic_helper_cleanup_planes(dev, state);
 
-       drm_atomic_state_free(state);
+       drm_atomic_state_put(state);
 
        spin_lock(&priv->lock);
        priv->pending &= ~commit->crtcs;
@@ -254,6 +254,7 @@ int exynos_atomic_commit(struct drm_device *dev, struct drm_atomic_state *state,
 
        drm_atomic_helper_swap_state(state, true);
 
+       drm_atomic_state_get(state);
        if (nonblock)
                schedule_work(&commit->work);
        else
index 27b0e34dadecdadafd6506148a49dd450ca5106d..6c7bb87f764e3b2a0c2fac16ce8e2b374d570421 100644 (file)
@@ -3941,10 +3941,9 @@ static void hsw_trans_edp_pipe_A_crc_wa(struct drm_i915_private *dev_priv,
 
        ret = drm_atomic_commit(state);
 out:
-       drm_modeset_unlock_all(dev);
        WARN(ret, "Toggling workaround to %i returns %i\n", enable, ret);
-       if (ret)
-               drm_atomic_state_free(state);
+       drm_modeset_unlock_all(dev);
+       drm_atomic_state_put(state);
 }
 
 static int ivb_pipe_crc_ctl_reg(struct drm_i915_private *dev_priv,
index ad8d712ae84c044bbd65fa48c3f510590a97016f..a12e093c54cf7ad073ee9955a619431e2011843a 100644 (file)
@@ -3582,7 +3582,7 @@ void intel_prepare_reset(struct drm_i915_private *dev_priv)
        return;
 
 err:
-       drm_atomic_state_free(state);
+       drm_atomic_state_put(state);
 }
 
 void intel_finish_reset(struct drm_i915_private *dev_priv)
@@ -3643,6 +3643,8 @@ void intel_finish_reset(struct drm_i915_private *dev_priv)
                intel_hpd_init(dev_priv);
        }
 
+       if (state)
+               drm_atomic_state_put(state);
        drm_modeset_drop_locks(ctx);
        drm_modeset_acquire_fini(ctx);
        mutex_unlock(&dev->mode_config.mutex);
@@ -6882,7 +6884,7 @@ static void intel_crtc_disable_noatomic(struct drm_crtc *crtc)
 
        dev_priv->display.crtc_disable(crtc_state, state);
 
-       drm_atomic_state_free(state);
+       drm_atomic_state_put(state);
 
        DRM_DEBUG_KMS("[CRTC:%d:%s] hw state adjusted, was enabled, now disabled\n",
                      crtc->base.id, crtc->name);
@@ -11249,8 +11251,8 @@ found:
        return true;
 
 fail:
-       drm_atomic_state_free(state);
-       drm_atomic_state_free(restore_state);
+       drm_atomic_state_put(state);
+       drm_atomic_state_put(restore_state);
        restore_state = state = NULL;
 
        if (ret == -EDEADLK) {
@@ -11279,10 +11281,9 @@ void intel_release_load_detect_pipe(struct drm_connector *connector,
                return;
 
        ret = drm_atomic_commit(state);
-       if (ret) {
+       if (ret)
                DRM_DEBUG_KMS("Couldn't release load detect pipe: %i\n", ret);
-               drm_atomic_state_free(state);
-       }
+       drm_atomic_state_put(state);
 }
 
 static int i9xx_pll_refclk(struct drm_device *dev,
@@ -12350,8 +12351,7 @@ retry:
                        goto retry;
                }
 
-               if (ret)
-                       drm_atomic_state_free(state);
+               drm_atomic_state_put(state);
 
                if (ret == 0 && event) {
                        spin_lock_irq(&dev->event_lock);
@@ -14437,7 +14437,7 @@ static void intel_atomic_commit_tail(struct drm_atomic_state *state)
 
        drm_atomic_helper_commit_cleanup_done(state);
 
-       drm_atomic_state_free(state);
+       drm_atomic_state_put(state);
 
        /* As one of the primary mmio accessors, KMS has a high likelihood
         * of triggering bugs in unclaimed access. After we finish
@@ -14520,6 +14520,7 @@ static int intel_atomic_commit(struct drm_device *dev,
        intel_shared_dpll_commit(state);
        intel_atomic_track_fbs(state);
 
+       drm_atomic_state_get(state);
        if (nonblock)
                queue_work(system_unbound_wq, &state->commit_work);
        else
@@ -14561,9 +14562,8 @@ retry:
                goto retry;
        }
 
-       if (ret)
 out:
-               drm_atomic_state_free(state);
+       drm_atomic_state_put(state);
 }
 
 /*
@@ -16305,8 +16305,8 @@ retry:
                dev_priv->display.optimize_watermarks(cs);
        }
 
-       drm_atomic_state_free(state);
 fail:
+       drm_atomic_state_put(state);
        drm_modeset_drop_locks(&ctx);
        drm_modeset_acquire_fini(&ctx);
 }
@@ -16943,10 +16943,9 @@ void intel_display_resume(struct drm_device *dev)
        drm_modeset_acquire_fini(&ctx);
        mutex_unlock(&dev->mode_config.mutex);
 
-       if (ret) {
+       if (ret)
                DRM_ERROR("Restoring old state failed with %i\n", ret);
-               drm_atomic_state_free(state);
-       }
+       drm_atomic_state_put(state);
 }
 
 void intel_modeset_gem_init(struct drm_device *dev)
index 73a521fdf1bdf760e7d487f0e632b80020e43e49..be3e04623e2aa4d69e621af4ed2b23fc4d87f187 100644 (file)
@@ -987,9 +987,7 @@ int intel_sprite_set_colorkey(struct drm_device *dev, void *data,
                drm_modeset_backoff(&ctx);
        }
 
-       if (ret)
-               drm_atomic_state_free(state);
-
+       drm_atomic_state_put(state);
 out:
        drm_modeset_drop_locks(&ctx);
        drm_modeset_acquire_fini(&ctx);
index cf83f6507ec8211566f87cbf4878e5d76c3eff0b..db61aa5f32ef7127eef08d2d15b808ad4e568e94 100644 (file)
@@ -83,7 +83,7 @@ static void mtk_atomic_complete(struct mtk_drm_private *private,
        drm_atomic_helper_wait_for_vblanks(drm, state);
 
        drm_atomic_helper_cleanup_planes(drm, state);
-       drm_atomic_state_free(state);
+       drm_atomic_state_put(state);
 }
 
 static void mtk_atomic_work(struct work_struct *work)
@@ -110,6 +110,7 @@ static int mtk_atomic_commit(struct drm_device *drm,
 
        drm_atomic_helper_swap_state(state, true);
 
+       drm_atomic_state_get(state);
        if (async)
                mtk_atomic_schedule(private, state);
        else
index 73bae382eac3acad17460a782e6422ec992a7963..db193f83529805e1255135a459ae7763b04c35b3 100644 (file)
@@ -141,7 +141,7 @@ static void complete_commit(struct msm_commit *c, bool async)
 
        kms->funcs->complete_commit(kms, state);
 
-       drm_atomic_state_free(state);
+       drm_atomic_state_put(state);
 
        commit_destroy(c);
 }
@@ -256,6 +256,7 @@ int msm_atomic_commit(struct drm_device *dev,
         * current layout.
         */
 
+       drm_atomic_state_get(state);
        if (nonblock) {
                queue_work(priv->atomic_wq, &c->work);
                return 0;
index e1cfba51cff64d11971a8cb0740e6c56faf7b690..1735c7accf727bfd9bd6cbc8c1710b081ae8864b 100644 (file)
@@ -105,7 +105,7 @@ static void omap_atomic_complete(struct omap_atomic_state_commit *commit)
 
        dispc_runtime_put();
 
-       drm_atomic_state_free(old_state);
+       drm_atomic_state_put(old_state);
 
        /* Complete the commit, wake up any waiter. */
        spin_lock(&priv->commit.lock);
@@ -176,6 +176,7 @@ static int omap_atomic_commit(struct drm_device *dev,
        /* Swap the state, this is the point of no return. */
        drm_atomic_helper_swap_state(state, true);
 
+       drm_atomic_state_get(state);
        if (nonblock)
                schedule_work(&commit->work);
        else
index bd9c3bb9252c68520af8233412c69253bfd04838..c76ed9ee6a01c816896422cdc14a9e1e3aedb7d8 100644 (file)
@@ -264,7 +264,7 @@ static void rcar_du_atomic_complete(struct rcar_du_commit *commit)
 
        drm_atomic_helper_cleanup_planes(dev, old_state);
 
-       drm_atomic_state_free(old_state);
+       drm_atomic_state_put(old_state);
 
        /* Complete the commit, wake up any waiter. */
        spin_lock(&rcdu->commit.wait.lock);
@@ -330,6 +330,7 @@ static int rcar_du_atomic_commit(struct drm_device *dev,
        /* Swap the state, this is the point of no return. */
        drm_atomic_helper_swap_state(state, true);
 
+       drm_atomic_state_get(state);
        if (nonblock)
                schedule_work(&commit->work);
        else
index 2784919a73664c6287e7d5812839347d572011ca..7087499969bc18a233ca22e4eb7b34adfaf20c0b 100644 (file)
@@ -184,7 +184,7 @@ static void sti_atomic_complete(struct sti_private *private,
        drm_atomic_helper_wait_for_vblanks(drm, state);
 
        drm_atomic_helper_cleanup_planes(drm, state);
-       drm_atomic_state_free(state);
+       drm_atomic_state_put(state);
 }
 
 static void sti_atomic_work(struct work_struct *work)
@@ -217,6 +217,7 @@ static int sti_atomic_commit(struct drm_device *drm,
 
        drm_atomic_helper_swap_state(state, true);
 
+       drm_atomic_state_get(state);
        if (nonblock)
                sti_atomic_schedule(private, state);
        else
index 8ab47b502d8382f9740e6795e56bf0afd545b632..a9630c2d6cb335029ea7197fa39a30f6479e7205 100644 (file)
@@ -63,7 +63,7 @@ static void tegra_atomic_complete(struct tegra_drm *tegra,
        drm_atomic_helper_wait_for_vblanks(drm, state);
 
        drm_atomic_helper_cleanup_planes(drm, state);
-       drm_atomic_state_free(state);
+       drm_atomic_state_put(state);
 }
 
 static void tegra_atomic_work(struct work_struct *work)
@@ -96,6 +96,7 @@ static int tegra_atomic_commit(struct drm_device *drm,
 
        drm_atomic_helper_swap_state(state, true);
 
+       drm_atomic_state_get(state);
        if (nonblock)
                tegra_atomic_schedule(tegra, state);
        else
index a694977c32f4bfb88448aec5e604536db2f14a5d..147fb28287ae331561eb719a582a151e213b92ef 100644 (file)
@@ -143,8 +143,6 @@ static int tilcdc_commit(struct drm_device *dev,
 
        drm_atomic_helper_cleanup_planes(dev, state);
 
-       drm_atomic_state_free(state);
-
        return 0;
 }
 
index c1f65c6c8e601e9331768ca040a5609cad686b2e..f31f72af8551f355add021c99667191743a04d92 100644 (file)
@@ -61,7 +61,7 @@ vc4_atomic_complete_commit(struct vc4_commit *c)
 
        drm_atomic_helper_cleanup_planes(dev, state);
 
-       drm_atomic_state_free(state);
+       drm_atomic_state_put(state);
 
        up(&vc4->async_modeset);
 
@@ -173,6 +173,7 @@ static int vc4_atomic_commit(struct drm_device *dev,
         * current layout.
         */
 
+       drm_atomic_state_get(state);
        if (nonblock) {
                vc4_queue_seqno_cb(dev, &c->cb, wait_seqno,
                                   vc4_atomic_complete_commit_seqno_cb);
index c52f99415c556532b3e894173e79ad491b808683..fc8af53b18aa5fba3422250dafcb60eb458cc539 100644 (file)
@@ -153,6 +153,7 @@ struct __drm_connnectors_state {
 
 /**
  * struct drm_atomic_state - the global state object for atomic updates
+ * @ref: count of all references to this state (will not be freed until zero)
  * @dev: parent DRM device
  * @allow_modeset: allow full modeset
  * @legacy_cursor_update: hint to enforce legacy cursor IOCTL semantics
@@ -164,6 +165,8 @@ struct __drm_connnectors_state {
  * @acquire_ctx: acquire context for this atomic modeset state update
  */
 struct drm_atomic_state {
+       struct kref ref;
+
        struct drm_device *dev;
        bool allow_modeset : 1;
        bool legacy_cursor_update : 1;
@@ -193,7 +196,33 @@ static inline void drm_crtc_commit_get(struct drm_crtc_commit *commit)
 struct drm_atomic_state * __must_check
 drm_atomic_state_alloc(struct drm_device *dev);
 void drm_atomic_state_clear(struct drm_atomic_state *state);
-void drm_atomic_state_free(struct drm_atomic_state *state);
+
+/**
+ * drm_atomic_state_get - acquire a reference to the atomic state
+ * @state: The atomic state
+ *
+ * Returns a new reference to the @state
+ */
+static inline struct drm_atomic_state *
+drm_atomic_state_get(struct drm_atomic_state *state)
+{
+       kref_get(&state->ref);
+       return state;
+}
+
+void __drm_atomic_state_free(struct kref *ref);
+
+/**
+ * drm_atomic_state_put - release a reference to the atomic state
+ * @state: The atomic state
+ *
+ * This releases a reference to @state which is freed after removing the
+ * final reference. No locking required and callable from any context.
+ */
+static inline void drm_atomic_state_put(struct drm_atomic_state *state)
+{
+       kref_put(&state->ref, __drm_atomic_state_free);
+}
 
 int  __must_check
 drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state);
index 43cf193e54d666be087c5962ac82401f0db3782e..02353904cdba7523183fd57ae9623b53283a3294 100644 (file)
@@ -88,7 +88,6 @@ struct drm_plane_state {
        struct drm_atomic_state *state;
 };
 
-
 /**
  * struct drm_plane_funcs - driver plane control functions
  */