Extend the scoreboard approach from the previous commit to used blocks,
so drm_buddy_print() can report per-order allocation pressure in O(1).
Unlike free blocks, an allocated block can leave the allocated state
through mark_free() (normal free and gpu_buddy_block_trim()) or be
consumed directly by gpu_block_free() during coalescing. Both sites are
guarded by gpu_buddy_block_is_allocated() and paired with the increment
in mark_allocated().
v3:
- Assert scoreboard is empty at fini(), as sanity check (Matthew Auld)
v2:
- Update after fix for use-after-free in split_block() call sites
- Change goto label to out_free_used_scoreboard for clarity
- Make drm_buddy_print() and gpu_buddy_print() symmetric for used and
free
Assisted-by: GitHub Copilot:claude-sonnet-4.6
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://lore.kernel.org/r/20260522092600.32818-6-francois.dugast@intel.com
Signed-off-by: Francois Dugast <francois.dugast@intel.com>
Francois Dugast
25d912475e