xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

drm: mm: track free areas implicitly

Browse Source 
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>
This commit is contained in:
Daniel Vetter
2011-02-18 17:59:12 +01:00
committed by Dave Airlie
parent 31a5b8ce8f
commit ea7b1dd448
2 changed files with 223 additions and 258 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
include/drm/drm_mm.h
View File

@@ -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)
*/