drm/msm: validate display and event threads

While creating display and event threads per crtc, validate
them before setting their priorities.

changes in v2:
	- use dev_warn (Abhinav Kumar)
changes in v3:
	- fix compilation error
changes in v4:
	- Remove Change-Id (Sean Paul)
	- Keep logging within 80 char limit (Sean Paul)

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Jeykumar Sankaran <jsanka@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>

diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index 4904d0d..dcff812 100644 (file)
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -553,17 +553,18 @@ static int msm_drm_init(struct device *dev, struct drm_driver *drv)
                        kthread_run(kthread_worker_fn,
                                &priv->disp_thread[i].worker,
                                "crtc_commit:%d", priv->disp_thread[i].crtc_id);
-               ret = sched_setscheduler(priv->disp_thread[i].thread,
-                                                       SCHED_FIFO, &param);
-               if (ret)
-                       pr_warn("display thread priority update failed: %d\n",
-                                                                       ret);
-
                if (IS_ERR(priv->disp_thread[i].thread)) {
                        dev_err(dev, "failed to create crtc_commit kthread\n");
                        priv->disp_thread[i].thread = NULL;
+                       goto err_msm_uninit;
                }
 
+               ret = sched_setscheduler(priv->disp_thread[i].thread,
+                                        SCHED_FIFO, &param);
+               if (ret)
+                       dev_warn(dev, "disp_thread set priority failed: %d\n",
+                                ret);
+
                /* initialize event thread */
                priv->event_thread[i].crtc_id = priv->crtcs[i]->base.id;
                kthread_init_worker(&priv->event_thread[i].worker);
@@ -572,6 +573,12 @@ static int msm_drm_init(struct device *dev, struct drm_driver *drv)
                        kthread_run(kthread_worker_fn,
                                &priv->event_thread[i].worker,
                                "crtc_event:%d", priv->event_thread[i].crtc_id);
+               if (IS_ERR(priv->event_thread[i].thread)) {
+                       dev_err(dev, "failed to create crtc_event kthread\n");
+                       priv->event_thread[i].thread = NULL;
+                       goto err_msm_uninit;
+               }
+
                /**
                 * event thread should also run at same priority as disp_thread
                 * because it is handling frame_done events. A lower priority
@@ -580,34 +587,10 @@ static int msm_drm_init(struct device *dev, struct drm_driver *drv)
                 * failure at crtc commit level.
                 */
                ret = sched_setscheduler(priv->event_thread[i].thread,
-                                                       SCHED_FIFO, &param);
+                                        SCHED_FIFO, &param);
                if (ret)
-                       pr_warn("display event thread priority update failed: %d\n",
-                                                                       ret);
-
-               if (IS_ERR(priv->event_thread[i].thread)) {
-                       dev_err(dev, "failed to create crtc_event kthread\n");
-                       priv->event_thread[i].thread = NULL;
-               }
-
-               if ((!priv->disp_thread[i].thread) ||
-                               !priv->event_thread[i].thread) {
-                       /* clean up previously created threads if any */
-                       for ( ; i >= 0; i--) {
-                               if (priv->disp_thread[i].thread) {
-                                       kthread_stop(
-                                               priv->disp_thread[i].thread);
-                                       priv->disp_thread[i].thread = NULL;
-                               }
-
-                               if (priv->event_thread[i].thread) {
-                                       kthread_stop(
-                                               priv->event_thread[i].thread);
-                                       priv->event_thread[i].thread = NULL;
-                               }
-                       }
-                       goto err_msm_uninit;
-               }
+                       dev_warn(dev, "event_thread set priority failed:%d\n",
+                                ret);
        }
 
        ret = drm_vblank_init(ddev, priv->num_crtcs);