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drm/ttm: optimize bo_kmap_type values 

A micro-optimization on the function ttm_kmap_obj_virtual().

By defining the values of enum ttm_bo_kmap_obj::bo_kmap_type to have a
bit indicating iomem, size of the function ttm_kmap_obj_virtual() will be
reduced by 16 bytes on x86_64 (gcc 4.1.2).

ttm_kmap_obj_virtual() may be heavily used, when buffer objects are
accessed via wrappers, that work for both kinds of memory addresses:
iomem cookies and kernel virtual.

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit is contained in:
Pekka Paalanen 2009-08-17 01:18:38 +03:00 committed by Dave Airlie
parent 949ef70e2d
commit a0724fcf82
1 changed files with 6 additions and 6 deletions
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12
include/drm/ttm/ttm_bo_api.h
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@ -245,14 +245,15 @@ struct ttm_buffer_object {
* premapped region.
*/
#define TTM_BO_MAP_IOMEM_MASK 0x80
struct ttm_bo_kmap_obj {
void *virtual;
struct page *page;
enum {
ttm_bo_map_iomap,
ttm_bo_map_vmap,
ttm_bo_map_kmap,
ttm_bo_map_premapped,
ttm_bo_map_iomap = 1 | TTM_BO_MAP_IOMEM_MASK,
ttm_bo_map_vmap = 2,
ttm_bo_map_kmap = 3,
ttm_bo_map_premapped = 4 | TTM_BO_MAP_IOMEM_MASK,
} bo_kmap_type;
};
@ -522,8 +523,7 @@ extern int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type);
static inline void *ttm_kmap_obj_virtual(struct ttm_bo_kmap_obj *map,
bool *is_iomem)
{
*is_iomem = (map->bo_kmap_type == ttm_bo_map_iomap ||
map->bo_kmap_type == ttm_bo_map_premapped);
*is_iomem = !!(map->bo_kmap_type & TTM_BO_MAP_IOMEM_MASK);
return map->virtual;
}