AcoSail/kernel_optimize_test
8
0
Fork 0
forked from luck/tmp_suning_uos_patched
Code Pull Requests Activity

drm/ttm: Optimize vm locking using kref_get_unless_zero v3

Browse Source 
Removes the need for a write lock each time we call ttm_bo_unref().

v2: Remove an unused variable.
v3: Really remove the unused variable.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit is contained in:
Thomas Hellstrom 2012-11-21 14:53:21 +00:00 committed by Dave Airlie
parent 5293908afa
commit 82fe50bcc8
2 changed files with 3 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
drivers/gpu/drm/ttm/ttm_bo.c
View File

@ -696,6 +696,7 @@ static void ttm_bo_release(struct kref *kref)
struct ttm_bo_device *bdev = bo->bdev;
struct ttm_mem_type_manager *man = &bdev->man[bo->mem.mem_type];
write_lock(&bdev->vm_lock);
if (likely(bo->vm_node != NULL)) {
rb_erase(&bo->vm_rb, &bdev->addr_space_rb);
drm_mm_put_block(bo->vm_node);
@ -707,18 +708,14 @@ static void ttm_bo_release(struct kref *kref)
ttm_mem_io_unlock(man);
ttm_bo_cleanup_refs_or_queue(bo);
kref_put(&bo->list_kref, ttm_bo_release_list);
write_lock(&bdev->vm_lock);
}
void ttm_bo_unref(struct ttm_buffer_object **p_bo)
{
struct ttm_buffer_object *bo = *p_bo;
struct ttm_bo_device *bdev = bo->bdev;
*p_bo = NULL;
write_lock(&bdev->vm_lock);
kref_put(&bo->kref, ttm_bo_release);
write_unlock(&bdev->vm_lock);
}
EXPORT_SYMBOL(ttm_bo_unref);

4
drivers/gpu/drm/ttm/ttm_bo_vm.c
View File

@ -259,8 +259,8 @@ int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
read_lock(&bdev->vm_lock);
bo = ttm_bo_vm_lookup_rb(bdev, vma->vm_pgoff,
(vma->vm_end - vma->vm_start) >> PAGE_SHIFT);
if (likely(bo != NULL))
ttm_bo_reference(bo);
if (likely(bo != NULL) && !kref_get_unless_zero(&bo->kref))
bo = NULL;
read_unlock(&bdev->vm_lock);
if (unlikely(bo == NULL)) {