Currently the exynos driver calls drm_vblank_off() with the event_lock held, while drm_vblank_off() will lock vbl_time and vblank_time_lock. This lock dependency chain conflicts with the one in drm_handle_vblank() where we first lock vblank_time_lock and then the event_lock.
Fix this by removing the above drm_vblank_off() calls which are in fact never executed: drm_dev->vblank_disable_allowed is only ever non-zero during driver init, until it's set in {fimd,vidi}_subdrv_probe. Both the driver init and open code is protected by drm_global_mutex, so the earliest page flip ioctl can happen only after vblank_disable_allowed is set to 1. Thus {fimd,vidi}_finish_pageflip - with pending flip events - will always get called with vblank_disable_allowed being 1.
Signed-off-by: Imre Deak imre.deak@intel.com --- drivers/gpu/drm/exynos/exynos_drm_fimd.c | 12 ------------ drivers/gpu/drm/exynos/exynos_drm_vidi.c | 12 ------------ 2 files changed, 24 deletions(-)
diff --git a/drivers/gpu/drm/exynos/exynos_drm_fimd.c b/drivers/gpu/drm/exynos/exynos_drm_fimd.c index e69b7c4..2eb131c 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_fimd.c +++ b/drivers/gpu/drm/exynos/exynos_drm_fimd.c @@ -623,7 +623,6 @@ static void fimd_finish_pageflip(struct drm_device *drm_dev, int crtc) struct drm_pending_vblank_event *e, *t; struct timeval now; unsigned long flags; - bool is_checked = false;
spin_lock_irqsave(&drm_dev->event_lock, flags);
@@ -633,8 +632,6 @@ static void fimd_finish_pageflip(struct drm_device *drm_dev, int crtc) if (crtc != e->pipe) continue;
- is_checked = true; - do_gettimeofday(&now); e->event.sequence = 0; e->event.tv_sec = now.tv_sec; @@ -645,15 +642,6 @@ static void fimd_finish_pageflip(struct drm_device *drm_dev, int crtc) drm_vblank_put(drm_dev, crtc); }
- if (is_checked) { - /* - * don't off vblank if vblank_disable_allowed is 1, - * because vblank would be off by timer handler. - */ - if (!drm_dev->vblank_disable_allowed) - drm_vblank_off(drm_dev, crtc); - } - spin_unlock_irqrestore(&drm_dev->event_lock, flags); }
diff --git a/drivers/gpu/drm/exynos/exynos_drm_vidi.c b/drivers/gpu/drm/exynos/exynos_drm_vidi.c index e26d455..4b0c16b 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_vidi.c +++ b/drivers/gpu/drm/exynos/exynos_drm_vidi.c @@ -382,7 +382,6 @@ static void vidi_finish_pageflip(struct drm_device *drm_dev, int crtc) struct drm_pending_vblank_event *e, *t; struct timeval now; unsigned long flags; - bool is_checked = false;
spin_lock_irqsave(&drm_dev->event_lock, flags);
@@ -392,8 +391,6 @@ static void vidi_finish_pageflip(struct drm_device *drm_dev, int crtc) if (crtc != e->pipe) continue;
- is_checked = true; - do_gettimeofday(&now); e->event.sequence = 0; e->event.tv_sec = now.tv_sec; @@ -404,15 +401,6 @@ static void vidi_finish_pageflip(struct drm_device *drm_dev, int crtc) drm_vblank_put(drm_dev, crtc); }
- if (is_checked) { - /* - * don't off vblank if vblank_disable_allowed is 1, - * because vblank would be off by timer handler. - */ - if (!drm_dev->vblank_disable_allowed) - drm_vblank_off(drm_dev, crtc); - } - spin_unlock_irqrestore(&drm_dev->event_lock, flags); }