Currently drm-buddy does not have full knowledge of continuous memory.
Lets consider scenario below.
order 1: L R
order 0: LL LR RL RR
for order 1 allocation, it can offer L or R or LR+RL.
For now, we only implement L or R case for continuous memory allocation.
So this patch aims to implement the LR+RL case.
Signed-off-by: xinhui pan <[email protected]>
---
drivers/gpu/drm/drm_buddy.c | 56 ++++++++++++++++++++++++++++++++-----
1 file changed, 49 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/drm_buddy.c b/drivers/gpu/drm/drm_buddy.c
index 11bb59399471..550af558342e 100644
--- a/drivers/gpu/drm/drm_buddy.c
+++ b/drivers/gpu/drm/drm_buddy.c
@@ -386,6 +386,37 @@ alloc_range_bias(struct drm_buddy *mm,
return ERR_PTR(err);
}
+static struct drm_buddy_block *
+find_continuous_blocks(struct drm_buddy *mm,
+ int order,
+ struct drm_buddy_block **rn)
+{
+ struct list_head *head = &mm->free_list[order];
+ struct drm_buddy_block *node, *parent, *free_node;
+
+ list_for_each_entry(free_node, head, link) {
+ node = free_node;
+ parent = node->parent;
+ while (parent && parent->right == node) {
+ node = parent;
+ parent = node->parent;
+ }
+ if (!parent)
+ continue;
+
+ node = parent->right;
+ while (drm_buddy_block_is_split(node))
+ node = node->left;
+
+ if (drm_buddy_block_is_free(node) &&
+ drm_buddy_block_order(node) == order) {
+ *rn = node;
+ return free_node;
+ }
+ }
+ return NULL;
+}
+
static struct drm_buddy_block *
get_maxblock(struct list_head *head)
{
@@ -637,7 +668,7 @@ int drm_buddy_alloc_blocks(struct drm_buddy *mm,
struct list_head *blocks,
unsigned long flags)
{
- struct drm_buddy_block *block = NULL;
+ struct drm_buddy_block *block = NULL, *rblock = NULL;
unsigned int min_order, order;
unsigned long pages;
LIST_HEAD(allocated);
@@ -689,17 +720,28 @@ int drm_buddy_alloc_blocks(struct drm_buddy *mm,
break;
if (order-- == min_order) {
+ if (!(flags & DRM_BUDDY_RANGE_ALLOCATION) &&
+ min_order != 0 && pages == BIT(order + 1)) {
+ block = find_continuous_blocks(mm,
+ order,
+ &rblock);
+ if (block)
+ break;
+ }
err = -ENOSPC;
goto err_free;
}
} while (1);
- mark_allocated(block);
- mm->avail -= drm_buddy_block_size(mm, block);
- kmemleak_update_trace(block);
- list_add_tail(&block->link, &allocated);
-
- pages -= BIT(order);
+ do {
+ mark_allocated(block);
+ mm->avail -= drm_buddy_block_size(mm, block);
+ kmemleak_update_trace(block);
+ list_add_tail(&block->link, &allocated);
+ pages -= BIT(order);
+ block = rblock;
+ rblock = NULL;
+ } while (block);
if (!pages)
break;
--
2.34.1