Am 07.03.22 um 15:37 schrieb Arunpravin:
place BUG_ON(order < min_order) outside do..while
loop as it fails Unigine Heaven benchmark.
Unigine Heaven has buffer allocation requests for
example required pages are 161 and alignment request
is 128. To allocate the remaining 33 pages, continues
the iteration to find the order value which is 5 and
when it compares with min_order = 7, enables the
BUG_ON(). To avoid this problem, placed the BUG_ON
check outside of do..while loop.
Well using BUG_ON sounds like the wrong approach in the first place.
A BUG_ON() is only justified if you prevent further data corruption,
e.g. when you detect for example a reference count overflow or similar.
In all other cases you should trigger a WARN_ON() and abort the
operation with -EINVAL if possible.
Regards,
Christian.
Signed-off-by: Arunpravin <Arunpravin.PaneerSelvam@xxxxxxx>
---
drivers/gpu/drm/drm_buddy.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_buddy.c b/drivers/gpu/drm/drm_buddy.c
index 72f52f293249..ed94c56b720f 100644
--- a/drivers/gpu/drm/drm_buddy.c
+++ b/drivers/gpu/drm/drm_buddy.c
@@ -669,10 +669,11 @@ int drm_buddy_alloc_blocks(struct drm_buddy *mm,
order = fls(pages) - 1;
min_order = ilog2(min_page_size) - ilog2(mm->chunk_size);
+ BUG_ON(order < min_order);
+
do {
order = min(order, (unsigned int)fls(pages) - 1);
BUG_ON(order > mm->max_order);
- BUG_ON(order < min_order);
do {
if (flags & DRM_BUDDY_RANGE_ALLOCATION)
base-commit: 8025c79350b90e5a8029234d433578f12abbae2b
