diff options
| author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2011-02-18 17:59:12 +0100 |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2011-02-23 10:32:34 +1000 |
| commit | ea7b1dd44867e9cd6bac67e7c9fc3f128b5b255c (patch) | |
| tree | 2feb9852ab18e2f726136ae460e414ef40425129 /include/drm | |
| parent | 31a5b8ce8f3bf20799eb68da9602de2bee58fdd3 (diff) | |
| download | lwn-ea7b1dd44867e9cd6bac67e7c9fc3f128b5b255c.tar.gz lwn-ea7b1dd44867e9cd6bac67e7c9fc3f128b5b255c.zip | |
drm: mm: track free areas implicitly
The idea is to track free holes implicitly by marking the allocation
immediatly preceeding a hole.
To avoid an ugly corner case add a dummy head_node to struct drm_mm
to track the hole that spans to complete allocation area when the
memory manager is empty.
To guarantee that there's always a preceeding/following node (that might
be marked as hole_follows == 1), move the mm->node_list list_head to the
head_node.
The main allocator and fair-lru scan code actually becomes simpler.
Only the debug code slightly suffers because free areas are no longer
explicit.
Also add drm_mm_for_each_node (which will be much more useful when
struct drm_mm_node is embeddable).
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'include/drm')
| -rw-r--r-- | include/drm/drm_mm.h | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h index 0d791462f7b2..34fa36f2de70 100644 --- a/include/drm/drm_mm.h +++ b/include/drm/drm_mm.h @@ -42,23 +42,24 @@ #endif struct drm_mm_node { - struct list_head free_stack; struct list_head node_list; - unsigned free : 1; + struct list_head hole_stack; + unsigned hole_follows : 1; unsigned scanned_block : 1; unsigned scanned_prev_free : 1; unsigned scanned_next_free : 1; + unsigned scanned_preceeds_hole : 1; unsigned long start; unsigned long size; struct drm_mm *mm; }; struct drm_mm { - /* List of free memory blocks, most recently freed ordered. */ - struct list_head free_stack; - /* List of all memory nodes, ordered according to the (increasing) start - * address of the memory node. */ - struct list_head node_list; + /* List of all memory nodes that immediatly preceed a free hole. */ + struct list_head hole_stack; + /* head_node.node_list is the list of all memory nodes, ordered + * according to the (increasing) start address of the memory node. */ + struct drm_mm_node head_node; struct list_head unused_nodes; int num_unused; spinlock_t unused_lock; @@ -74,9 +75,11 @@ struct drm_mm { static inline bool drm_mm_initialized(struct drm_mm *mm) { - return mm->free_stack.next; + return mm->hole_stack.next; } - +#define drm_mm_for_each_node(entry, mm) list_for_each_entry(entry, \ + &(mm)->head_node.node_list, \ + node_list); /* * Basic range manager support (drm_mm.c) */ |