From: Daniel Vetter Date: Thu, 21 Jan 2021 15:29:52 +0000 (+0100) Subject: drm/komeda: Annotate dma-fence critical section in commit path X-Git-Tag: accepted/tizen/unified/20230118.172025~6402^2~28^2~743 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=53fc08c23a323884d11b178d12ce55043690eb0f;p=platform%2Fkernel%2Flinux-rpi.git drm/komeda: Annotate dma-fence critical section in commit path Like the helpers, nothing special. Well except not, because we the critical section extends until after hw_done(), since that's the last thing which could hold up a subsequent atomic commit. That means the wait_for_flip_done is included, but that's not a problem, we're allowed to call dma_fence_wait() from signalling critical sections. Even on our own fence (which this does), it's just a bit confusing. But in a way those last 2 function calls are already part of the fence signalling critical section for the next atomic commit. Reading this I'm wondering why komeda waits for flip_done() before calling hw_done(), which is a bit backwards (but hey hw can be special). Might be good to throw a comment in there that explains why, because the original commit that added this just doesn't. v2: Small rebase Reviewed-by: James Qian Wang (v1) Cc: "James (Qian) Wang" Cc: Liviu Dudau Cc: Mihail Atanassov Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20210121152959.1725404-5-daniel.vetter@ffwll.ch --- diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_kms.c b/drivers/gpu/drm/arm/display/komeda/komeda_kms.c index 034ee08..aeda4e5 100644 --- a/drivers/gpu/drm/arm/display/komeda/komeda_kms.c +++ b/drivers/gpu/drm/arm/display/komeda/komeda_kms.c @@ -73,6 +73,7 @@ static const struct drm_driver komeda_kms_driver = { static void komeda_kms_commit_tail(struct drm_atomic_state *old_state) { struct drm_device *dev = old_state->dev; + bool fence_cookie = dma_fence_begin_signalling(); drm_atomic_helper_commit_modeset_disables(dev, old_state); @@ -85,6 +86,8 @@ static void komeda_kms_commit_tail(struct drm_atomic_state *old_state) drm_atomic_helper_wait_for_flip_done(dev, old_state); + dma_fence_end_signalling(fence_cookie); + drm_atomic_helper_cleanup_planes(dev, old_state); }