drm/vc4: Rework UPM allocation to avoid double buffering #6385
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
6by9
force-pushed
the
rpi-6.6.y-drm2
branch
4 times, most recently
from
3c45267
to
21bec0f
Compare
The previous UPM allocation was done per plane state, when there is no overlap of usage between frames. Allocate per plane, and only change the allocation if the required size changes. We have to reference count as plane states can be duplicated. Signed-off-by: Dave Stevenson <[email protected]>
This reverts commit c7b98a6.
LBM is only relevant for each active dlist, so there is no need to double-buffer the allocations. Cache the allocations per plane so that we can ensure the allocations are possible. Signed-off-by: Dave Stevenson <[email protected]>
6by9
force-pushed
the
rpi-6.6.y-drm2
branch
from
21bec0f
to
50e3301
Compare
Seeing as it is userspace that creates the state and commit that is validated, drop the log messages to debug to avoid userspace being able to totally spam the kernel log. Signed-off-by: Dave Stevenson <[email protected]>
|
These patches are now cleanly rejecting commits that exceed LBM or UPM limits. We reuse the allocations if they are of the same size as the previous user of the plane, but will allocate a new buffer when it changes (that will double buffer, but it is a relatively rare event to have significant changes). Probably hold off merging until the stable image has been bumped, but review comments welcome. |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
The previous UPM allocation was done per plane state, when there is no overlap of usage between frames.
Allocate per plane, and only change the allocation if the required size changes. We have to reference count as plane states can be duplicated.