[PATCH 05/18] drm: Introduce an iterator over holes in the drm_mm range manager

Chris Wilson
2012-10-19T17:04:56Z

This will be used i915 in forthcoming patches in order to measure the
largest contiguous chunk of memory available for enabling chipset
features.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Airlie <airlied@redhat.com>
---
drivers/gpu/drm/drm_mm.c | 55 +++++++++++++++-------------------------------
include/drm/drm_mm.h | 26 ++++++++++++++++++++++
2 files changed, 44 insertions(+), 37 deletions(-)

diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c
index 5db8c20..c3d11ec 100644
--- a/drivers/gpu/drm/drm_mm.c
+++ b/drivers/gpu/drm/drm_mm.c
@@ -102,20 +102,6 @@ int drm_mm_pre_get(struct drm_mm *mm)
}
EXPORT_SYMBOL(drm_mm_pre_get);

-static inline unsigned long drm_mm_hole_node_start(struct drm_mm_node *hole_node)
-{
- return hole_node->start + hole_node->size;
-}
-
-static inline unsigned long drm_mm_hole_node_end(struct drm_mm_node *hole_node)
-{
- struct drm_mm_node *next_node =
- list_entry(hole_node->node_list.next, struct drm_mm_node,
- node_list);
-
- return next_node->start;
-}
-
static void drm_mm_insert_helper(struct drm_mm_node *hole_node,
struct drm_mm_node *node,
unsigned long size, unsigned alignment,
@@ -127,7 +113,7 @@ static void drm_mm_insert_helper(struct drm_mm_node *hole_node,
unsigned long adj_start = hole_start;
unsigned long adj_end = hole_end;

- BUG_ON(!hole_node->hole_follows || node->allocated);
+ BUG_ON(node->allocated);

if (mm->color_adjust)
mm->color_adjust(hole_node, color, &adj_start, &adj_end);
@@ -168,15 +154,10 @@ struct drm_mm_node *drm_mm_create_block(struct drm_mm *mm,
{
struct drm_mm_node *hole, *node;
unsigned long end = start + size;
+ unsigned long hole_start;
+ unsigned long hole_end;

- list_for_each_entry(hole, &mm->hole_stack, hole_stack) {
- unsigned long hole_start;
- unsigned long hole_end;
-
- BUG_ON(!hole->hole_follows);
- hole_start = drm_mm_hole_node_start(hole);
- hole_end = drm_mm_hole_node_end(hole);
-
+ drm_mm_for_each_hole(hole, mm, hole_start, hole_end) {
if (hole_start > start || hole_end < end)
continue;

@@ -361,8 +342,10 @@ void drm_mm_remove_node(struct drm_mm_node *node)
== drm_mm_hole_node_end(node));
list_del(&node->hole_stack);
} else
- BUG_ON(drm_mm_hole_node_start(node)
- != drm_mm_hole_node_end(node));
+ BUG_ON(node->start + node->size !=
+ list_entry(node->node_list.next,
+ struct drm_mm_node, node_list)->start);
+

if (!prev_node->hole_follows) {
prev_node->hole_follows = 1;
@@ -420,6 +403,8 @@ struct drm_mm_node *drm_mm_search_free_generic(const struct drm_mm *mm,
{
struct drm_mm_node *entry;
struct drm_mm_node *best;
+ unsigned long adj_start;
+ unsigned long adj_end;
unsigned long best_size;

BUG_ON(mm->scanned_blocks);
@@ -427,17 +412,13 @@ struct drm_mm_node *drm_mm_search_free_generic(const struct drm_mm *mm,
best = NULL;
best_size = ~0UL;

- list_for_each_entry(entry, &mm->hole_stack, hole_stack) {
- unsigned long adj_start = drm_mm_hole_node_start(entry);
- unsigned long adj_end = drm_mm_hole_node_end(entry);
-
+ drm_mm_for_each_hole(entry, mm, adj_start, adj_end) {
if (mm->color_adjust) {
mm->color_adjust(entry, color, &adj_start, &adj_end);
if (adj_end <= adj_start)
continue;
}

- BUG_ON(!entry->hole_follows);
if (!check_free_hole(adj_start, adj_end, size, alignment))
continue;

@@ -464,6 +445,8 @@ struct drm_mm_node *drm_mm_search_free_in_range_generic(const struct drm_mm *mm,
{
struct drm_mm_node *entry;
struct drm_mm_node *best;
+ unsigned long adj_start;
+ unsigned long adj_end;
unsigned long best_size;

BUG_ON(mm->scanned_blocks);
@@ -471,13 +454,11 @@ struct drm_mm_node *drm_mm_search_free_in_range_generic(const struct drm_mm *mm,
best = NULL;
best_size = ~0UL;

- list_for_each_entry(entry, &mm->hole_stack, hole_stack) {
- unsigned long adj_start = drm_mm_hole_node_start(entry) < start ?
- start : drm_mm_hole_node_start(entry);
- unsigned long adj_end = drm_mm_hole_node_end(entry) > end ?
- end : drm_mm_hole_node_end(entry);
-
- BUG_ON(!entry->hole_follows);
+ drm_mm_for_each_hole(entry, mm, adj_start, adj_end) {
+ if (adj_start < start)
+ adj_start = start;
+ if (adj_end > end)
+ adj_end = end;

if (mm->color_adjust) {
mm->color_adjust(entry, color, &adj_start, &adj_end);
diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h
index 4020f96..d710a10 100644
--- a/include/drm/drm_mm.h
+++ b/include/drm/drm_mm.h
@@ -89,6 +89,19 @@ static inline bool drm_mm_initialized(struct drm_mm *mm)
{
return mm->hole_stack.next;
}
+
+static inline unsigned long drm_mm_hole_node_start(struct drm_mm_node *hole_node)
+{
+ BUG_ON(!hole_node->hole_follows);
+ return hole_node->start + hole_node->size;
+}
+
+static inline unsigned long drm_mm_hole_node_end(struct drm_mm_node *hole_node)
+{
+ return list_entry(hole_node->node_list.next,
+ struct drm_mm_node, node_list)->start;
+}
+
#define drm_mm_for_each_node(entry, mm) list_for_each_entry(entry, \
&(mm)->head_node.node_list, \
node_list)
@@ -99,6 +112,19 @@ static inline bool drm_mm_initialized(struct drm_mm *mm)
entry != NULL; entry = next, \
next = entry ? list_entry(entry->node_list.next, \
struct drm_mm_node, node_list) : NULL) \
+
+/* Note that we need to unroll list_for_each_entry in order to inline
+ * setting hole_start and hole_end on each iteration and keep the
+ * macro sane.
+ */
+#define drm_mm_for_each_hole(entry, mm, hole_start, hole_end) \
+ for (entry = list_entry((mm)->hole_stack.next, typeof(struct drm_mm_node), hole_stack); \
+ &entry->hole_stack != &(mm)->hole_stack ? \
+ hole_start = drm_mm_hole_node_start(entry), \
+ hole_end = drm_mm_hole_node_end(entry) : \
+ 0; \
+ entry = list_entry(entry->hole_stack.next, typeof(struct drm_mm_node), hole_stack))
+
/*
* Basic range manager support (drm_mm.c)
*/
--
1.7.10.4